Exotic X - Baja-BC

well good morning everybody welcome to the inside of the home the local time is 8 41 on a sunday morning very brisk outside it's even brisk in the front porch so we're going to be indoors today and if you want to get the geology content and only the geology content then you go ahead now you go ahead and skip ahead um 18 minutes and that will be the beginning of the geology program if you're watching live and you'll only like the geology content i guess go take a walk around the block and come back we'll see at the top of the hour but for many of us here uh uh in live contact we're gonna uh say hi to some folks and do some thank yous and and see where people are watching from so thank you for joining us this morning this morning's topic is baja bc a very challenging topic and so once we get started i'll be doing my best to keep it all straight for you got some new stuff for you this morning and our most recent meeting was less than 48 hours ago talking about pluton so thank you so much for joining us check my laptop real quick how are we doing are we functional and where are you viewing from uh peter johnson says good sound that's nice to hear steve's in the portland area al good morning 5x5 says garrett from the netherlands hello garrett david is feeling like things are functional for us audio and visual wise this morning there's also i'm sorry too much that went by there very quickly pat good morning from yakima i kind of have these this periodic real quick scroll here so i'll catch what i can carry is in bainbridge island greece is here again hey nice to see you uh palm beach florida don is in los angeles thomas is in germany greetings thomas another don in fairbanks alaska greg in seattle lorraine in blodgett oregon 5x5 thank you for the report lorraine or lawrence i'm nobody kathy is defined okay so kat nobody's talking to kathy rachel's in a plane hello rachel uh allison's in oakland california glenn is in philadelphia geologically speaking hello todd we enjoyed your video uh last time gem cat from bowmanville ontario good morning grab me by the lakes that's five by five well this is all very pleasant and wonderful to see yeah you see uh oh gary back country gary oh we have this weird i turn very very i'll just try to be aware of that yeah we've got the lights set up etc steve from victovia bc so you bet that's back country gary's a wonderful photograph that's been on our wall now for a week or so ryan is in wilmington north carolina we'll do a couple more especially from people from distant lands and then we'll get started with a few thank yous if you don't mind we have more than 300 already uh terrific uh oliver bc tacoma it's just great just great to have you all with us i'm so grateful that you tune in each time uh rainey ketchikan alaska wichita kansas krista hello okay um quarter to the hour um ireland did i see uh jennifer good morning we we enjoy your videos as well so there's lots of different folks here with different backgrounds and different uh abilities and talents we all know that and let's uh let's demonstrate that with a couple of the gifts that have come in recently from a box arrived from barcelona spain this is from robert and sesay in barcelona nick in the place where i live catalunya we have strange traditions one of them is a figure in the nativity scene you normally would not expect it's called a looks like cogner to me but i think i saw some spelling of the con kanaye or something like that sorry here no nativity scene is complete without it but should be well hidden my wife and i hope you like him he is a wine drinker using a parone a traditional glass wine pitcher so here's a nativity scene and you know this customs declaration and everything for do you know what robert's talking about so here's the concept sorry patrick come on this is culture now and in the box from spain amazing a yogurt container from barcelona and inside a figure thank you robert and cece from barcelona spain so glad that you could enjoy us here and uh appreciate your gift thank you i'll do more reading about that uh about that not to be outdone we have garrett from the netherlands who sent a large box and garrett i uh i already put your box to use for a hildebrand map and derek sorry garrett says uh thank you for the outstanding live streams a token of our appreciation i have a few presents for you an owl with led lighting for the garden so garrett has been watching us in the middle of the night even back in the spring and i i think i christened him the dutch night owl and so he's taken that to heart so he sent me a finale the led light solar paneled i don't know the dutch night owl says yeah man and garrett the night owl the dutch night i always says here's a floor mat with uh bijou on it and many other things in your box there garrett but i don't know if people can see i didn't take the time to set them up sorry this is uh bijou the cat and garrett the dutch night owl oh can you see that maybe not and there was more stuff in there too so thank you very much he created a website called dutchnightowl.com and is hoping to visit washington state at some point here's his hometown the village of lauren gelderland and east uh east netherlands so thank you garrett very much for your box very much appreciated andre just stopped by he's a neighbor he's the guy that sent the christmas cookies i i i didn't make that connection you had a different address on there andre so he's a former geologist and and gifted this huge geologic atlas of the rockies and i will add this to our collection in the department thank you andre larry and chris larry and christine sent a cute little box that's written by larry my wife and i have been long time fans greatly appreciate all the energy you put into sharing geology we're constantly amused by how much you use food as your props and as a joke we thought we should get you plastic food so you can keep using them without being tempted to consume your teaching tools having failed at finding suitable plastic german chocolate cake or crinkle cut fries we ended up with soaps that look like your favorite food prop so please enjoy these fruit cake and german chocolate cake soaps maybe you can use them as props or for hygienic purposes either way have a great holiday season larry and christine from mountain view california so here's the german chocolate cake soap smells like german chocolate cake and also smells like soap and some fruit cake soap what in the world uh ajs no aj sweetsoap.com ajsweet soap.com fruitcake soap thanks you guys down in the bay area of san francisco wow amazing and finally one more thank you this morning very large box from newport oregon this is from lissa and john in newport oregon uh very nice things teachers liz mother uh and uh for also i'll read it in recognition of your selfless contribution to sharing your knowledge with many of us throughout the world and for other teachers in the family your wife lives your mother your son who is also sharing their knowledge with future generations and in deference to your friendship with randy lewis so this goes back to the spring when i was visiting with randy lewis and local native american who i will continue to film with this month by the way and willingness to incorporate his native american stories with historical geologic events please accept this pendleton blanket titled keep my fires burning each year pendleton has issued a different commemorative blanket designed by native american artists to honor native american culture keep my fires burning was released in 2002 and no longer produced for hundreds of years native americans have passed down their knowledge from the elders to the next generation keep my fires burning pays respect to the tribal elders and storytellers the wisdom keepers in recognition of the important role they play in handing down teaching beliefs and spiritual direction to children and future generations hope your family can get many uses many years of use out of this as a bed cover wall hanging or cozy fort construct and be able to pass this down through the generations we will do that in addition to passing down our heritage our history and knowledge also included are two masks each large for you and regular for liz these 3d masks give more room between your mouth and the mask and have a sewn in h-e-p-a filter between the fabric layers and are made by a patient of mine with donated fabric finally we include a photo on vacation this fall in the olympic peninsula where we found and i'm not kidding there is no freaking way thanks and appreciation for all you and other teachers do all right so this is a real sign on the olympic peninsula no freaking way a nice card uh uh i tried this mask on and it fits i think better than any other mask i've had extra large so i'll be using this teaching this um winter on campus i've been a bandanna guy to this point but this one is uh extremely comfortable and there's another big one and then there's uh regular size face masks for liz but you want to see the pendleton blanket i'm sure you heard there uh a little too big to show you properly but we will treasure your gift thank you okay i got two minutes according to my watch can i uh double check one more time that we are doing okay and i won't have to think about that again are we doing okay and say hi can i say hi to a couple more people and then we will begin our program shortly more than 600 now good uh 5x5 thank you perfect picture and audio wonderful i hear bijoux so i gotta go figure out what's going on there paul and robert thank you for the report uh hello lock han from india welcome it's incredible that i can be speaking live to people on the other side of the planet i i i know i've said that before but i just can't believe it okay wonderful i've got one minute according to my watch and today's going to take some extra con lis you're there with with john thank you thank you i'm glad that you're with us daryl good morning uh okay i got to get my head right uh today's a challenge so thank you for joining us i will see you in one minute oh okay shall we get your screen time happening right away should we get you get your moment in the sun um and yeah you can sit and you can just hang out in your pillow right here while we're talking but these guys i know like to see you and those that are not into this are nauseated but you know seems like most people really enjoy seeing you and you've been out shivering for quite a while so i think you're probably ready to curl up here in the bay window right behind the larry the ladder so i think you should do that are you about ready to fall asleep right now are you gonna take a little cat nap no pun intended does the ear twitch mean yes are you saying hi to those guys oh you're purring now oh my goodness oh okay i gotta start yep oh that's max oh god we gotta i'm gonna be afraid of max it's okay okay 30 seconds ugh go on a two-hour run huh okay excuse me bijou's into the sausage that's one of the food props so i gotta move that quick hey get off the laptop get away from the sausage back away from the sausage please get off the laptop hey please get off the laptop well hello everybody thank you so much for joining us this morning it's a very brisk sunday morning here in ellensburg washington usa i'm your host nick zetner i teach geology right over there at central washington university and just beyond that campus is mount stewart and the mount stewart pluton and the north cascades and the exotic terrains that we've been discussing all of this fall you know who i am by now i assume this is not the first time you've joined us uh this is a series and we're almost done with the series there's just one more weekend to go and today is a particular challenge so i've been hearing from some of you and hearing that things are just kind of slipping away from you a little bit maybe more than a little bit like it's it's not bing crosby and a model t going down the sunset highway for sure it's complicated stuff but that was kind of the plan from the start wasn't it i was going to try to learn new stuff every time and even though we get into the hornet's nest and it's complicated we do our best to make to make it worthwhile now we got papers flying because bees are the cat hang on another second please who invited the cat and so it usually takes me a while to get us into it and the introductory folder has many pages in it but i'm going to warn you that it's going to be a long intro today and i don't want you to view it as an intro necessarily i want you to view it as a way that we can really set up a couple of the major payoffs for ourselves this morning and i do have brand new stuff so if you feel like you've already heard about baja bc you've already seen me do a baja bc live stream last spring is this just a rehash of that it is not to keep in the spirit of this fall series i've tried to push myself to learn as much new stuff as possible and i made a couple of breakthroughs last night just for myself and possibly for you and also early this morning my eyes popped open at 3 30 this morning with baja bc on the brain so i've been busy this morning trying to think carefully about what i want to do with you this morning and we're gonna start right now okay so i should show you the three-act play i should show you the three-act play here it is once we get ourselves uh together and we've reviewed enough that we feel like we're ready for the new stuff i want to restore the big sausage i'll need to explain that won't i uh we will go back to the nanaimo you remember we talked about the nanaimo before but we will find some important data in the nanaimo sedimentary layers in southern british columbia and northern san juan islands for act two and we do have a video field report from southern california that arrived in my inbox uh at like 8 30 last night from chris in torrance california and chris is going to show us some polona schist which was vaguely part of the plan but now it's for sure part of the plan because of chris's uh video field report so three act play but before we get into it i feel like it's especially important for us to remind ourselves of what we've done uh and especially situations that we've done before that are going to be paying off for us today awkwardly stated but let's go ahead so we're pretty much done with this mapping mcmap and i remind you that we had two major dates do you recall this as we put british columbia together what were the two major dates 170 million years ago and 100 million years ago and that was by looking at these major exotic terrains in british columbia quinnelia cash creeks to kenya alexander rengelia and we decided that these two blue guys the twins with cash creek in between was considered the inter montane super terrain that accreted to the western edge of north america 170 million years ago that's a negotiable date but in that neighborhood and then the main event as i've been saying for a while and some late comers have been going why are you keep teasing the main event what's the main event well we've already talked about it the main event is rangalia and alexander together being called the insular super terrain guerrero by the way down in baja same time same concept that's the insular super terrain that added to the western edge of north america 100 million years ago today we don't really care whether north america is plowing into the insular or vice versa we just have the main event a hundred million years ago adding the insular super terrain what's the insular super terrain rengelia alexander and guerrero down in baja mexico it's the insular super terrain the thing that got added 100 million years ago that is the centerpiece of baja bc so we're not going really to the blue mountains or the foothills of the sierras or you know whatever the kettle falls washington that's too far in board for us today we want to stay outboard baja bc is mainly an outboard story it's most clearly an outboard story now there can be some discussion at some point late today if we're still feeling like we're in the mood to possibly do some northward movement of intermontane but that's not our main focus our main focus is insular super terrain the super terrain that added to the western edge of north america 100 million years ago and you're like what's baja bc then well this is actually part two i don't know if you saw friday's show i was edgy because i lost the live stream and had to restart the whole thing and never did recover kind of spiritually so i get a little grouchy when i have that situation but hopefully we can get past that uh assuming we're live streaming beautifully this morning i'll stay nice and warm and fuzzy and mister rogers-ish but the point is we already got started on baja bc last time so if you're watching this in replay possibly if you really want to do it uh completely you stop now you go back to the last show called plutons and you get introduced to merle beck and paleomagnetism and these major batholis i'll i'll remind you but that's the thorough treatment and so we're picking up from that show and continuing with the concept of baja bc so we're not starting cold with baja bc as my point this morning for those of us that have been with us every time okay i'm not used to being indoors i can't find half my stuff so this is the other map we've been building together you and i this is all the exotic terrains in the north cascades and we're not going to go through every terrain again but i don't think i hit this hard enough on friday i want to hit it hard right now are you ready i said kind of casually but i want to say more forcefully now these are the north cascades of northern washington they are part of the coast plutonic complex and did you catch it last time it's the coast plutonic complex the cpc that used to be almost 2 000 miles further to the south so we're talking about baja bc in this series because everything on this map or most everything on this map according to baja bc is from southern california slash northern baja mexico and you're like wait no you said mount stewart was but not the rest of this stuff yeah i'm saying everything else too and so the main thrust of today is to look for more than just the paleomagnetic batholith evidence for baja bc there's some stuff on this map that we've grown to love the skagit this walking metal nanaimo etc there's emerging data from these units that say they were further south so take this north cascades map and send it north between 85 and 55 million years if you wouldn't mind now that reminds me we're still introducing the topic you know that i'm a teacher right you know that i don't do any research my job is to teach my job is to take research hopefully new research and fold it into what i'm doing i think that's the best way to teach science and you've gotten to know me over the years hell you're in my house right now and for some that's too much it's too much me and you it feels like a a prima donna talking about himself all the time but there's there's a reason that i'm sharing so much of myself i'm not trying to sell you anything i'm not trying to sell you anything i'm not trying to make any money i'm not trying to use this live stream series for some sort of personal advantage for any any tangible reason i just do it because i like doing it and i think it's important to say that specifically this morning because quite often when you get in discussions with geologists about this there are two very firm camps and those camps those those trenches no pun intended between the baja b seers and the non-baja b seers or the mobilists and the fixes or the translation people and the none that's all tied to their whole career they've been they've been doing their research so they are reluctant to think about what the other side says because they've already invested time and money and their whole professional reputation depends upon it so as i talk to more and more of these folks who are pro and con baja bc they are they are in their foxhole and uh they're getting tired they're getting tired of going back and forth and the baja bc people and i promise we'll get to the data in just a second in the new stuff i think this is important to set the stage this way some of the baja bc people are feeling like boy we're just this is maybe just going to go away like we it's still a minority opinion we can't convince everybody that this is a thing and i don't really i'm not sure there's any young people even working on this stuff so i'm not pushing one side of the other obviously i lean towards the baja bc side but i'm a straddler i'm happy to listen to everybody and try to report as much as i can now that said you'll hear mostly pro baja bc stuff from me this morning but brian mahoney is a former classmate at idaho state university back in the 1980s i've visited a little bit by with a few other people who are not into baja bc we can talk about that but you're hearing me i'm not trying to push or sell a particular idea because it will benefit me somehow okay he goes to the introductory folder quarter after this my town this is my view most mornings i just saw it this morning that's the stuart range and the mount stewart pluton sometimes called a bassliff but it's pretty small so let's call it a pluton for today and this is the mountain range that started it all and merle beck who watched friday's show and emailed me uh friday night uh i wants to add a couple of things i'll report his his new um tidbits for us in a second but this is where it all began and i'm reminding you that i get reminded of this baja bc thing every time i look north to the stewart range and yes if you're a baja bc person uh this was sent to me as a joke happy birthday nick with a mexican flag on top of mount stewart here's liz hiking a couple summers ago i know it's probably late fall and there's mount stewart of course but then in the foothills surrounding mount stewart as all this uh ingles exotic terrain the ophiolite and part of the ophelite is the serpentinite i didn't know much about it at the time i know much more thanks to our series this fall and when liz breaks open a piece and shows the inside of one of these brown to orange rocks it's this beautiful green rock so the context the host rock for a lot of this baja bc plutonic material is this green stuff and the question is is the green stuff from mexico as well yeah so i've done how many times i've showed you this this is our visit but now we're looking at this with hopefully a new set of eyes couched in today's topic most of what you see here was in mexico or was in southern california at least based on more of the data coming today are you seeing why we need to take our time to set this up yes we've looked at this yes we know we're not talking about all the plutons the very young plutons these are millions of years old are way too young for our story what was the age of baja bc from last time we're going to move all this crust we're going to move the insular super terrain from mexico to british columbia between 85 and 55 million years ago so only some of these dates are from baja bc time meaning and some some of the dates are from before baja bc time including mount stewart mount stewart is 93 million years old that's before we begin the northward movement also just trying to get you kind of get these things dusted off it's just been friday since we did it but you know for those that haven't had a wonderful weekend haven't thought much about this since then let's go for it north cascades part of a massive batholith belt called the coast plutonic complex i always struggle with that we're going to call this the cpc the rest of today for mainly for me okay the cpc is in bc okay cpc north cascades part of the cpc and even if we take out the straight creek fault we can continue a bunch of the north cascades geology across the border and into that cpc this is the thing that was in mexico you need evidence we looked at some of the evidence from merle beck last time gary gary it's from mexico if you're a baja bc person and i think i'll just for simplicity i'll just say we i'll just say us just ba we're talking baja bc i lean that way anyway okay you already know that i'm i'm trying to be open to everybody but i'm not going to go back and forth constantly so you're looking at mostly rocks that were originally in mexico that's a crazy thing to say you better have some evidence boy you better have some evidence now we know from last time that all those plutons acting together are something called a batholith and the long lasting story is an eastward subduction story of the farallon plate down to the east's abduction as daryl cowan said in a recent email i kind of like that phrase i'm going to steal that one daryl down to the east versus down to the west that's a little bit more descriptive than just saying eastward subduction so we briefly visited with bob hildebrand's concept of slab failure slab break off we're not going to get hung up with that today but the point is we have massive amounts of pluton in the neighborhood of 100 million years ago batholis in other words that are happening before baja bc happens including places in southern california in the mojave desert today joshua tree national park is just one of dozens of natural areas in the mojave and south of the sierra nevadas that have this mid-cretaceous plutonic material so is it simple for us just to visualize this and to have our plutons forming as a result of this down to the east subduction of the fairlawn plate maybe so maybe that's just what we'll do today just because we're going to have enough to juggle in our head and i keep coming back to this in the san juan islands and other places we have our naps with our low angle thrust faults showing a major collisional event between roughly 185 million years ago that's been tied now generally to this major collision between the insular super terrain and this is before baja bc now this is just colliding this is accreting this stuff again i'm still reminding you that yes down to the east abduction is the main model uh but hildebrand was thinking that it makes more sense to do this let's not get hung up i think we're done okay so here we go so yes from mainly merle beck's work that we did last time this was the main conclusion i said more than two thousand i had to double check my notes merle um with his paleomagnetic work which we'll review very quickly right now uh says that there's 3 000 kilometers of northward movement of mount stewart that was his original statement and so that's a little less than 2 000 miles okay so almost 2 000 miles north between 85 and 55 million years ago insular and as we commented before conceptually it's great to have just this simple block moving north but that's just the concept and since we have not found a major strike slip fault that's from this time it's does that mean simply because we haven't found this major fault that this whole thing is baloney you're going to hear from me today the answer is no there's an amazing amount of work amazing amount of new data that's supporting this almost 2 000 miles worth of movement to the north but we don't necessarily have to have one major san andreas fault like structure to do the work so let's not get hung up on finding a major fault please still reviewing and getting you back into it so this is friday we focused on three major battle list the coast range the cpc in british columbia which includes north cascades just made that point the sierra nevada batholith and the peninsula ranges baffled you remember this from friday there was an interesting to me maybe to you split personality of the sierra nevadas older rocks in the west younger rocks in the east also a difference in the composition of the granites same split personality same basic age pattern older granites in the west younger in the east and according to hildebrand i'm still trying to figure that out evidence of major trauma at 100 million years ago in between those two boundaries now what is what are those boundaries are there thrust faults at the at this split is it a strike slip fault we're gonna visit that a little bit today and i had a lot of question marks with this there's apparently a split story in the in the cpc as well but i don't see that split easily here in the north cascades and the dates i could find are not the beautiful older in the west and younger in the east like we had further south so i'm still not sure what to do with that but apparently there is a western cpc and an eastern cpc and let's put that in the back of our minds as well but finally to merle beck's work which was the last act of friday uh merle helped us see that if you study the paleomagnetic signature of these batholiths bathylets are a bunch of plutons together there was a unusual paleomagnetic signature in the prb same on you identical unusual paleomagnetic signature in the cpc and a normal or not unusual in other words expected paleomagnetic signature of the sierra nevadas and so therefore based on this paleomag work merle said these two guys have moved north and also rotated clockwise with respect to interior north america since 100 million years ago and merle also said based on this paleo mag in the sierras sierra nevadas no rotation uh during this time during baja bc time and no northward translation and so we looked then at the fact that there was a good match granite wise between the prb and this year nevada batholith i'm now with new stuff today seeing that some geologists including will matthews i'm going to talk about will matthews a fair amount this morning i've never met him will matthew's from university of calgary he's showing a similar bedrock geology in the cpc i need to investigate more but that doesn't change our story here's the main story there's a perfect match paleomagnetically of these two guys but not the sierra nevadas same way that we did this on friday paleomagnetic match this discordant or unusual or low inclinated low inclination of the paleo mag with the cpc and the prb down in mexico and therefore the conclusion was those two batholiths possibly were together and were further south than they are now for sure and this guy has been in eastern california a long time so merle back in the 1970s 50 years ago starts publishing papers saying that we have a we have mount stewart and the rest of the cpc uh that moved 25 degrees north in 25 million years maybe up to 30 million years now and those are fast rates but not unusually fast rates for the way the world works today with plate motions still trying to get you into it beck saying today i see the cpc and the prb differently than i see the sierra nevadas i'm avoiding the idaho battle because i'm not sure what to do with it but i think there's not a major northward translation of the idaho batholith need to look into that and then merle says if we can just get these guys back down to where they were look at how far south according to the paleomagnetic data that the prb was and then of course this stuff that today is up in british columbia was much further south and notice that merle we're into the new stuff notice that merle has the cpc para park parallel park next to the sierra nevada batholith pausing now because this is new from this point on merle unwilling to take the cpc and slot it in but instead parallel park it right next to uh now just pull up next to this other car on the street so merle sent me an email and basically said did you want more papers to discuss and i said sure you can send me the the the references and then merle i'm sorry i got into all this other stuff that's brand new data that's different than paleomag and that will be the focus today so i'm just gonna if you're really into paleomag and you're wanting to get more merle back original papers there's a 1991 paper from merle a 1979 paper from merle i'll just let you kind of capture pause and and capture this if you're watching this in replay the original paper one of the original papers in 1973 with to sarah bill dickinson and bob butler uh with an anti-baja bc paper in 1998. i will read merle's quick notes here 1973 paper that was the original paper that hatched the whole caboodle 1979 paper it had been proposed that the western edge of middle america central america had suffered tectonic erosion this is moral talking by email friday night we suggested that it may have been translated northward instead of tectonically eroded 1991 the 1991 paper according to merle some gsa editors suggested that gordon gastil at san diego state and i do dueling paper sort of thing where i argued for northward displacement baja bc and gordon a good guy now deceased explained why it could not have been the papers appeared back to back in the early 90s and then finally the 1998 paper by bill dickinson and bob butler called coastal and baja california paleomagnetism reconsidered in gsa bulletin this is merle his comment on that paper this is the bill dickinson bob butler attempt to explain it all away in my view it founders on the observation that their varied mechanisms magically produce precisely the same result i sent bill dickinson a plot showing that the cretaceous polls from baja from igneous and sedimentary rocks located all over the place fell in a tight cluster that was no more scattered than the reference pole from the craton i felt that this was monumentally unlikely if each study if each separate study had been affected by its own specific problem i never heard back from bill okay so do you feel like you're ready for the new stuff do i feel like i'm ready for the new stuff [Applause] uh i tried scott patterson real quick remember scott from uh studying the mount stewart uh petrology of the granitic rocks there and also the chihuahuan shift and scott said uh uh happy to respond but i just can't handle this short time uh i don't i don't have time to reply with a long i'm swamped et cetera but he did say i would say one quick thing though um mount stewart pluton is pretty magnesium rich pretty unusual for putting it in a mojave location so you just can't use paleomagnetism data you must also match age and geochemistry of the host rocks and that's what we're going to do today to update you on work recent work in the last five to ten years where there's a growing case for the host rocks surrounding the batholis that were also telling a story of baja bc how you doing you okay 9 30 and he's starting folder one are you serious yeah this is going to be a long one i'm telling you that right up front and it's the first two folders that are going to be the lion's share of the work so we begin with restore the big sausage back where i'm from we call big sausages kill bosses back in the midwest in wisconsin so is that like a polar sausage or kielbasa and they're kind of curved typically but um took a walk yesterday downtown stopped in at the safeway and i found these which i've never had before but i bought them i don't know if i can pronounce this i'll just say big sausage i bought them because they're big sausages that are pretty straight there's two of them okay i'm going to call these kill bosses okay brings back a painful memory i would in high school i played basketball and my senior year was finally my time to get a lot of playing time and i had some skills down low defense and rebounding i could pass a little bit but i couldn't shoot to save my life like nikki get in there don't shoot that's literally what the head coach would say to me so the midway through my senior year uh the team was struggling to score and i wasn't scoring for sure and so the student section would start chanting kiyobasa kielbasa kielbasa steve irkey who was a one year younger than i and i was ahead of him on the death depth chart he could score he was built like a kill boss a big big beefy guy but he had a nice soft touch around the rim so the crowd eventually got their way kielbasa went in and i was out and by the end of the season i wasn't playing at all it was all kielbasa and it was a good coaching move they went on to the state tournament the following year and kilbasa was scoring like crazy but kill boss okay so what do i mean restore the big sausage restore kilbasa well some of you i noticed in the last show were wondering how can we get the cpc back down to baja bc and and how would it like slot in does it slot in and i had kind of the same question like here's a geologic map that's very complicated but basically here's a big sausage the sierra nevada batholith here's another big sausage the peninsula ranges batholith and then here's this disruption of these two batholis this is the mojave sonoran region or range or something and i'll just give you a few more maps we've looked at this right here's the sierra nevada batholith a big sausage and then the sausage has been cut and interrupted remember this we got a kielbasa or at least we have one hot dog and then we slice it and we offset it by the san andreas fault 300 miles of offset in the last 18 million years now let's not be confused the the san andreas is way too young for baja bc time please that's a big point we're going to be moving stuff we're going to be slicing kielbasa and making segments and everything but we're doing that here with the san andreas fault but that's today right this is still going on today we're trying to visualize were there san andreas fault-like structures slicing the kielbasa and offsetting the kilbasa into segments back between 85 and 55 to allow this northward transport you're like i'm starting to lose it that may be true but i gotta keep going okay more maps just showing we have part of the kielbasa here sierra nevadas there's that other batholith the peninsula ranges remember these do not match paleomagnetically with merle's work this never went north this moved north from further south in mexico but where's the cpc it's it's at jerome lessman's house it's mount stewart north of my town where did the cpc was it truly just parked right here as merle's map showed and daryl cowan i think also just kind of has the insular kind of down here parked next door so i didn't think as i was doing this kind of work i think i've told you before um three years ago about this time winter i was looking for something to do and i was learning as much as i could about the north cascades and getting up to speed so much of what we're doing now is stuff that i put together three years ago i just haven't used and let me show you what i put together i wondered did we have one big kielbasa once upon a time before baja bc before 85 million years ago before we start moving things north did all of the batholiths of the western court courtiera line up as one big kilbasa on a map are you following what i'm saying akilbasa where'd it go on a map do all of these mid-cretaceous batholiths the cpc the sierras or the sierras the cpc or the the salinas or the peninsula range were they all kind of continuous in one big kielbasa they're not today but were they back then so without really knowing better i just tried it i found a box in the basement it's a big one and the whole purpose of this box this is a new box for us the purpose of this box is to show you panels that i drew with my little colored pencils three years ago just wondering if i could restore the kielbasa the big sausage and get all of those bafflers to line up before 85 million years ago and i also include the baja bc concept so let me start just with the upper tier here i don't think i'll even narrate really dates rangalia i will narrate a bunch of ocean scraps green rocks coming in off of the ocean total cartoon time right no idea if i even know what i'm doing but eventually getting to today so i was really focused on the dot here which is mount stewart in mount stewart north of my town is the caboose of baja bc it's it's the southern end of this massive insular super terrain again i'm using the dates i'm using the cartoonish idea of one major strike slip fault which i don't think anybody really thinks is there but it's the concept that we want so that was one attempt and then i must have read a little bit more and i thought well let me try something different let me kind of do the same kind of thing but now let's get four hot dogs four segments of the kielbasa and let me line them up remember the kielbasa being one big long sausage so in these sketches starting 90 million years ago that's before 85 right that's before baja bc begins this is just me now i'm i'm taking papers i'm not totally dreaming it up but i'm i was getting confused i was just trying to put it together the best i could there's a reason i'm sharing this with you by the way so hot dog number one is the sierra nevada bath number two is the cpc number three is is it called the salinas salinas i don't know i'm not from down there it's another part of the batholith that's now been offset by the san andreas fault today and and there's the peninsula ranges okay so now i've got stewart again but i also have the san juan islands i was doing this in prep for uh we were going to film daryl cowan out at the san juan islands so again 90 million years ago here's rengelia coming in much further south than it is today that's the insular these two guys together the insular let's just continue the panels can't really see what i'm doing now and there's all sorts of things to show you here i don't want to spend the rest of the hour on this but my point was i wanted to try to restore that big sausage i it was pleasing to me to visualize this as one unbroken batholith that's my point and then we cut the sausage i don't need to do it with the props do i have a knife but i don't need to we're going to cut the kielbasa into segments and then notice we're going to remove we're going to remove the cpc completely from the rest of the kielbasa and that's the guy that has the paleomagnetic weirdness and then more recently today the salinas block has also been removed so today that's according to my little cartoons that's why we have the sierras and the peninsula ranges so close to each other they didn't form originally so close to each other but because of baja bc strike slip motion and then the more modern san andreas fault strike slip motion we can get that arrangement this is next week by the way celestia people keep asking what about celestia well we're not there yet so let's see it is after so let's see is younger than baja bc okay so it's so big i don't know how to do this uh i'll say one more thing have you noticed that [Music] this is an outboard story i've already said that meaning that baja bc is happening way out here in the very far west and if you're still not sure why the sierra nevada batholith why that segment of the kielbasa didn't move north it's because we need to restore california back before the clockwise rotation and the basin and range extension of the last 25 million years if we do that we can have this huge whale of baja bc migrate north up the coast and totally leave eastern california alone no idea if that worked but here's why i bothered you with it you know i'm not shy about emailing people whether they know who i am or not i just email them and say here's who i am and i've got some questions about your research and most of the time people are very busy and i totally understand and they reply but they usually just say i just got a couple minutes for you but here's a couple sentences but i got a long email from william matthews university of calgary dated january 8 2018 and he gave me three pages of text and at the time i read his wonderful email reply about my i didn't say kill boss i didn't want to sound like a total rube but i i showed him those maps and he had very specific like he took the sketches seriously and like gave me a lot of thought about the sketches and i want to read some of that to you and i now realize why he was working on something similar and he's not about he's not a baffled person at all he's a zircon person so that's coming in chapter two but i feel like i'll just cut to it he was working on this which i love and i'll just pause here for a second this is william matthews will matthews from calgary i think the date on this poster is 2017. i'm not exactly sure but in the last five years and i don't know how good you can read here but this is the peninsular batholith the western half of the coast plutonic complex and the sierra nevada basilis so from a totally different angle using detrital zircons and then anomalous sediments which are coming in the next folder he was doing he was restoring the kielbasa my words not his and i like this a lot not just because it works with my cartoons but it it it pleases me as far as the simplicity of restoring this now it's up for debate whether this is real or not of course within the baja bc community there might be massive disagreement about how to restore things but i want you in addition to noticing that he has restored the big sausage with the cpc between the sierras and the peninsula ranges basilis but please notice also he has a spreading ridge that's going to be subducted underneath north america we're getting complicated now but the point here so far is that we have a cooler plate moving north away from a spreading ridge that was a boundary between the cooler moving north and the fairlawn moving south and he is reconstructing an ocean floor you know i've been avoiding this a long time here's our first real careful look at what this might look like to explain why the movement if you're if you're kind of stuck on that right now like why are we even talking about northward movement how is that even possible if we have down to the east fairlawn plate subduction well if you're in the baja bc world you need a northward moving cooler plate i've already said that a number of times in past shows but the new thing is he has the boundary between the kula and the farallon in the below the waters of the pacific ocean intersecting with the coastline and therefore we're segmenting kielbasa and we're removing the cpc the western part of the cpc according to will and sending it the long journey north so now that you have the visual maybe i'll just show you this while i read a couple of his comments if you don't mind so he's commenting on my cartoons which are on the big box but here's his more professional version of some of the same stuff uh nick the paleomagnetic data is the real driver of the hypothesis hypothesis unlike psychology where studies don't seem to reproduce well paleomagnetists have now done dozens of studies that give consistent results while it is reasonable to argue that inclination flattening and pluton tilt affected the magnitude of northward displacements reported in some of the early studies these factors have now been corrected for and the results still indicate major northward translation your two sets of sketches seem to handle the cpc a little bit differently i guess i will show you mine so here's the first set of sketches and the second ones i'll just show you this part of it how about in your first set of sketches you cut the baffleth in half down in california and move the western half of the batholith north in your second set of sketches you move the whole cpc northward from southern california northern mexico you should pick one model and go for it well i'm showing both we know from various workers that the cpc at the latitude of prince george british columbia excuse me at the latitude of prince rupert british columbia comprises western and eastern batholis in the cpc with very different magmatic histories as i see it the eastern cpc was already somewhere well to the north by 80 million years ago and the western cpc was juxtaposed against it post 70 million years ago following its excision from the california mexico region this is similar to your second set of sketches except that there was already a bathoth in the north the eastern cpc when the block labeled two arrived in british columbia your handling of the selenium blocks and the second set of sketches is not consistent with most people's view of it that was a polite way to say that you're wrong your handling of the selenium blocks and the second set of sketches is not consistent with most people's views of it the selenium block is missing its western components such as the western older and more mafic parts of the batholith four arc and a creationary complex which is present to the north in the sierra nevada batholith and to the south in the peninsula ranges batholis i'm gonna keep going this is we're in the weeds now but i don't care hopefully you're still into this jacobson argued that these components were displaced to the south by left lateral displacement chapman argued these components were removed by tectonic erosion remember merle talking about that and erosion despite the issues jacobson had with this model i will will matthews think the selenium block set inboard of the baja bc block and these components were removed by northward displacement and it ended up in alaska that's coming on friday patrick we're going to alaska on friday however the observation of missing components of the normal tectonic succession is accommodated the general consensus is the selenium blocks likely sat just south of the sierra nevada batholith in the late cretaceous not well south of it i'm going to continue for a number of reasons hopefully if will sees this he won't be bothered i'm reading his email you know i do that and i haven't upset anybody yet i want you to see how a careful scientist can communicate with somebody he doesn't even know and spend you know probably an hour on this email very grateful for that and many geologists many scientists are very good by email they they they like to follow through they're very thorough people generally i'm skipping a couple paragraphs believe it or not but i want to add a little bit more from will this is three years ago i think it's much more likely that major northward translation was accompanied by transtension in the south which sent the baja bc block out to sea with oceanic crust forming behind it this is what is happening to baja mexico today the baja bc block then rotated northward and eventually collided dextro transpression with the north american plate somewhere near where it is today i don't know this guy oceanic crush created inboard of the baja bc block would have been subducted beneath north america during contraction i'm going to read you two more things the earlier the early paleomagnetists that's merle and others and even cowan 1997 that's daryl watching with us right now in the live comments were hesitant to put the baja bc block against north america as there was perceived to be no hole where a cretaceous baffleth was missing we now know gotta find that we now know that the batholith is missing in the mojave sonoran segment once san andreas displacement are reconciled in my opinion this hole was occupied by the western cpc therefore mount stewart batholith was just at the southern end of the baja bc block and would have intruded just north of the peninsula ranges batholith most of the geologists in california do not agree with my interpretation that the western cpc derived from mojave region all right we're not the folder two yet i'll just say it do you remember the split personality in all three of the major battles some are wondering if the cpc in british columbia has a split because it's a major shear zone because it's a major fault where the western side of the fault is moving north compared to the eastern side of the fault sound familiar so if you go to the cpc where there's all these plutons mid cretaceous plutons in western british columbia it's complicated apparently i've never been up there but they can see evidence of strike slip motion even though it's not a simple strike slip fault it's not brittle it's deeper it's exposed deeper and the idea is that what does it look like in the subsurface of a major strike slip fault is it squishier down there can you have right lateral offset with hundreds of miles of offset and have a sheared scene as opposed to a clean brittle break is it possible that this thing running down the middle of the cpc separating western cpc from eastern cpc is one of the big faults that allowed baja bc northward translation this is a paper in 1997 referred to by anybody writing a paper on baja bc note the author darrell cowan co-author of second edition of roadside geology of washington by marley miller and her former graduate school advisor darrell cowen university of washington daryl's with us again in the live chat you're going to hear from daryl in the cozy fort we interviewed him but this is his uh coming up with some crucial tests to try to keep this baja bc thing alive post-moral essentially and there has been some follow through on some of the crucial tests lobbed out there by daryl i hope you're doing okay seems like there's live comments uh scrolling by so it seems like we're functional we have 900 people i'm going to the other significant folder and then we'll just kind of finish folder three with kind of if we have any energy left but there's one major set of new ideas that are brand new to me some of that was new but this is new new to me double new new squared the nanaimo crystalline core west melange belt easton nook sack you remember all that stuff metal nanaimo let me remind you [Applause] sedimentary layers mostly our coastic sandstones but some clays some shales some conglomerates uh in this area here i think we colored it rose pink if i recall no was it flamingo one of those pink colors okay reminding you showing photos of the nanaimo i'll just say sandstone remember this guy he might be with us too live jerome lessman vancouver island university okay well we were talking about the nanaimo and the same show with the western melange belt and let me remind you of the basics of the nanaimo let's just say sandstone between 90 and 66 million years old now hang on that's kind of the time of baja bc is it not what's baja bc time and by that i mean when is everybody everybody moving north according to the theory the idea 85 to 55 okay well we're we're in that window and what is this this is sedimentary material that is sitting on top of the thing that's moving north holiday cookies from andre and his wife forget your name sorry sorry i let's think of the nanaimo as a bunch of sprinkles on top of the insular super terrain the nanaimo sediments are being deposited before and during baja bc movement so if we study the sprinkles and the detrital zircons that are in the sprinkles on top of the insular super terrain if we study the nanimo in other words we're not going to learn about the cookie the cookie's already been made that's the insular super terrain but by studying the sprinkles we can maybe if we're clever talk about how far south this cookie was it's moving north between 85 and 55 million years ago how could the sprinkles how could the sand made out of zircons tell us something about the past which reminds me we're going to cut when we're done we're going to cut this beautiful cake this brand new fruitcake from vinman's bakery you got to love it in downtown ellensburg washington we're going to make a nice big slice look at the inside of the fruitcake which is analogous to all the exotic terrains in the american west and we will do a toast to you while eating this beautiful sliver of new vinman's fruitcake okay so we talked about the nanaimo we talked about the zircons and how much detail you can get from the tiny little micro micrometer scale zircons we talked about the idea that the sprinkles are not just randomly sprinkled but they are sand grains the sprinkles are the sand grains made out of zircon minerals the sprinkles are coming by river from the east primarily especially late in the nanaimo story and notice that i have more than i have christmas colors i have more than one kind of sand one more than one uh source of the sand i'm setting you up now for what we've been able to learn from these zircons within the nanaimo sediments which are sprinkles on top of a christmas cookie my god how you're supposed to keep track of all this i'm asking a lot of you still reminding you of work we've done before oh i'm giving you some tells now i this is stuff i added last night but ignore this for now we were just talking about the nanaimo and the ages the swakin biotite nice that originally was more archosic sandstone in these age windows and then even the matau arcosic sandstones is there some sort of regional story here we're building to that still in reminder of phase here haven't gotten to the new stuff yet most view the nanaimo sediments and the metal sediments as sand grains deposited in a forearc basin for arc basin the basin you cross before you get to the volcanic ark and if you erode the volcanic ark there you have part of the kielbasa that's exposed for erosion new stuff go there are some brand new papers i'll show you that more in a second so here's will matthews the email is just telling you about from three years ago when he emailed me a bunch of slides here's one of uh here's a group from simon fraser university doing some more new work on the nymo worked a little bit with that paper here's a brand new paper that came out this year just a few months ago i think from i guess one of will matthews's students daniel coutts at university of calgary and what do they have to say detail now of the zircon within the nanaimo looking at the sprinkles on top of the insular super terrain christmas cookie between 90 and 72 million years ago there is a bunch of zircons that can be collected they've analyzed thousands of these zircons and if you're down low in the oldest part of the nanaimo apparently you can work with the details in these zircons to say some of the sand came from the west which must be eroded carmutz and basalt and other parts of rengelia allah jerome lessman country and then also rivers are bringing some of the zircon sand from the east and the western cpc no big story there the big story is that at 72 million years ago within the nymo sediments there's a major change there's an introduction of these things that i'm coloring green and those zircon sands are extremely old they are pre-cambrian in age there's no pre-cambrian zircon sand deposited in the nanaimo older than 72 but suddenly at 72 what the hell is going on sorry patrick we continue with our regular sands coming from the eroded sea western cpc to the east i know that's confusing but just part of the kielbasa is eroding and we're getting some of that sand in the nanaimo but the big story is what are we doing we got 35 of these sand grains deposited between seven daddies excited now between 72 and 66 million years ago that are coming from the pre-cambrian craton of north america this is going way back what was it the second show was it session b and we were talking about the craton the oldest part of north america and the strontium 706 line is it coming back to you now well there's eroded grains of the precambrian craton which is far to the east that are being brought by rivers and deposited in the nanaimo basin which is sitting on the insular super terrain so we're saying something about the movement history in a second of the insular super terrain because of these things being deposited on top of it the christmas cookie has sprinkles being added but the sprinkles are coming from two different sources i drew something for you would you like to see it this is based on the new papers that i just shared with you and i should find well let me just give you a second here first of all so i'm picking two dates both are during baja bc time are they not they're between 85 and 55. and this is showing a river flowing west taking eroded pieces of the cpc sand grains zircons taking them from the eroded let's say granite of the cpc it is part of the kielbasa and depositing the sprinkles on top of rengelia and the rest of the insular super terrain okay no big story there but remember at 72 million years ago things change and in addition to cpc zircons being deposited on top of the christmas cookie we have headward erosion and we have rivers now taking stuff directly from very very old craton and also adding them to the top of the christmas cookie why is that important i'm going to cut right to it in case i've lost maybe i've lost most of you but just in case i haven't just in case i haven't lost you yet why does the fact that we have extremely old zircon sands in the nanaimo on top of the insular why does that help us at all with learning about baja bc i thought we were talking about batholies i thought we were talking about paleomagnetism we're not right now we're talking about a completely different line of evidence the concept is this if we restore the old coastline of north america back to this time so i know that this coastline today this edge of the craton today is out in eastern california i know that but i'm restoring this back because we're removing the basin range extension and other things that have happened more recently okay and the concept is here's our river coming from the pre-cambrian craton carrying pre-cambrian zircon sands and depositing them on the insular super terrain but wait a minute if the insular super terrain is moving north we're going to break the river we're going to behead the river and the sprinkles on top of the christmas cookie will continue to ride on top of that northward moving christmas cookie is anybody still with me the question is at what part of the pre-cambrian craton did those green sprinkles come from did the pre-cambrian zircon sands come from there's two choices and merle back 50 years ago had his detractors and that's an understatement but it all centered on paleomagnetism and restoring mount stewart batholith and peninsula ranges bacillus understanding that paleomagnetic data this is a totally different set of data detrital zircons in the nanaimo sediments and this is also anti-baja bc pro baja bc can you see it there's a mountain range near where i did my master's thesis in central idaho i did mine in the southern tip of the beaverhead mountain range on the northern edge of the snake river plain do you know that country at all near craters of the moon but the next range to the west is called the lemhi range and in the lemhi range are pre-cambrian zircons in pre-cambrian basement rock and there is also places where we have pre-cambrian craton of the appropriate age exposed in today's mojave desert the mojave sonoran region and so the sprinkles on top of the christmas cookie bijo's into the cr kielbasa but i don't ah kielbasa you see it look we're going to remove the cpc from the kielbasa and send this to canada and leave this one in eastern california we got it i'll be right back hey we're almost done with the hard stuff in fact next friday will be easier because it's more recent and then a week from today will be just putting it all together i decided session z our last session a week from this morning we'll just be taking all this stuff and trying to put it together so if you're feeling frustrated right now that this has just gotten away from you and there's no way to come back there's a way to come back but we're into the heart of the deepest hardest stuff conceptually for today's show and also probably for the whole series so that's a little pep talk for you okay so i lost my train of thought but it's basically where did these pre-cambrian zircons come from and i've got some specific ages for you in just a second the debate that continues today brian mahoney for instance is a big proponent of these grains coming from the lemhai basin in central idaho paul link as well his former advisor will matthews stacia gordon and others kristen sauer mojave we need to know is there a way to distinguish between these two because the age of the precambrian rock here the age of the precambrian rock here both granitic in general are pretty similar and so it's not the smoking gun that maybe it could have been i'm saying mojave i'm leaning that way but i need to be open to the lemhai story as well and that brings into the effect or that sheds light on are you a baja bc person or a mojave bc person or a central idaho bc person there's different schools of thought for how far things moved north merle's baja bc is the extreme three thousand kilometers of northward transport that's from the paleomag data only some of this zircon stuff is saying possibly it's still full 3000 kilometers of northward transport but as we move north remember as we're restoring the kielbasa north the big change and the big batch of pre-cambrian zircons coming on to the sprinkles of the christmas cookie are coming at 72. that's already quite a ways into our northward transport so without knowing a whole lot i can see where this could still be a baja bc story not necessarily a mojave bc story because we've already done remember mount stewart areas and the the nanaimo is in the southern part of the cpc that's already that ship has already set north quite a ways okay i want to finish this hard part with reading a little bit from just a paragraph from stacia gordon who's part of this group oh boy oh boy oh boy okay are you as confused as this guy are you as trouble maker-ish what are you as um are you getting into a trouble as much as this guy is right now he screwed up all my paper piles he's essentially trying to get us to stop i think i think he's trying to get us to stop are you trying to get us to stop bijou bc i just saw that scroll by okay there's too many treats too many food props out here to tempt this guy uh yeah so the last folder and this will be brief because i know we're already way past time peninsula arranges basilisk this is the mojave area now peninsula ranges there's the southern tip of the sierra nevada two parts of the kielbasa oh the kielbasa used to be together that's my thought and will matthew's thought but we know this thing has already moved quite a bit further north and we have to slot a huge part of the kielbasa in here the cpc is a big freaking batholith it's a big section of the kielbasa that neat we need room for that and perhaps the salinas block as well where's that kirsten i'm now i need to i need basically just to set up hang on patrick it was on the ground blame the cat so here's another paper if you're deeply into this topic and this is mojave bc coming from kirsten shower the star student of stacia gordon there's many papers by kirsten sauer in the last five years you remember she was working in this gadget nice and the swat cane nice and the crystalline core here in the north cascades well she's also and this is the final thing we're going to try to do here is to find more evidence if you don't like the zircon and you don't like the paleomag here's the third major piece of evidence stacia gordon's group is finding these old precambrian zircons in more than the nanaimo mojave zircons according to this group and many groups oh yeah really nick because most of the stacia gordon now last week because most of the detrital zircons originally formed from magmatism we can use the age of these zircon cores to learn about what magmatic event formed them and then we can use that magnetic age to track where the zircons must have come from as there are only so many places that have that age of magnetism for example a combination of the really diagnostic pre-cambrian ages are she's talking about the pre-cambrian sprinkles on top of the christmas cookie right in the nanaimo really diagnostic ages are 1.38 billion years old and more zircon sand that is between 1.6 and 1.8 billion years old that in combination are indicative of the mojave or the lemhi sub-basin and thus if you find these pre-cambrian ages in your zircon it instantly suggests that those zircons must have come from one of those two places either in the mojave or the lemhi either from southern cala from southern california today or central idaho today we have observed these pre-cambrian ages of zircons in are you ready it's more than in the naimo the skagit nice the swat cane nice the nanaimo the western melange belt plus a lot of different meta sediments in oregon california and even alaska this is some of the evidence for mojave bc the havnium isotope composition of the zircon tells a lot of where the zircon formed in the crust versus the mantle like the detrital zircon ages their hafnium isotope composition can be used as an additional fingerprinting tool so i promise this is the last little part but suddenly we're realizing that there's more evidence yet to get the cpc down to the mojave in southern california these are some metamorphic shifts the polona shift that will be our video field report from chris and from torrance in just a second the orocopia schist and the rand schists these are isolated i just showed you that map these are isolated exposures because of the basin and range extension recently in the last 20 million years there's been crustal extension and a lot of their schists are under a bunch of alluvial material of half grab in age but if we piece together some of those exposures this is the same freaking stuff with the same precambrian zircons as many of the north cascades units that stacia just listed in her email and so i remind you that i had this in mind when i did this with you we were talking about what to me was a confusing thing how are you adding a bunch of sediment into the depths this is the geologic elevator going down and coming back up but we needed a bunch of sediment being added to that deep part of the magma system to explain a bunch of the zircon and other chemical details in those rocks well we said there's a remember i was shoveling sand in the barn there's a button sand there's a bunch of sand in the metal and the western melange belt and the nanaimo and in the original swat cane well they all have this similar mojave zircon story that's the best i can do for you there we wrap up honest to god with a couple final thoughts basil t cough came out west 15 years ago and tried majorly to contribute to the baja bc research he's from the university of wisconsin my alma mater wonderful guy had an hour-long zoom with him earlier this week and he's been specifically working in the western idaho shear zone or the western idaho suture zone if you know it that way and he thought possibly he could make a major leap forward in finding evidence for baja bc but this is a brand new talk that i'm going to share with you in the cozy fort just a little bit from from basil that he just gave this fall at gsa virtually of course and he now realizes that there was not major baja bc movement along the western idaho sheer zone this is new to me i knew that he was looking for a long time and this is where we have the intermontane in direct contact with the craton at the western idaho sheer zone his findings now tells him that there is a newly discovered palouse promontory that's basil's term this year for a block of the craton that is basically creating this corner at orofino idaho and because of this armpit this precambrian margin armpit that's important to us here because if you get some of this exotic terrain material into this slot it's stuck it can't move north even if it wants to because of this palouse promontory according to basil and his group and so he knows that that corner that orofino corner you see here's exotic terrains to the west and here's this old pre-cambrian margin again this is back to september but there's a big right-hand corner the orophino corner which is not allowing that kind of northward translation at least to the intermontane story so he thought this might be the smoking gun area for baja bc but it is not according to basil shenanigans galore with bijou the cat and there's been 30 degrees of rotation since that time so the present orientation of the corner uh was a little different back then now i'm just spitballing before we go to the cozy fort basil in that zoom call said hey i know i don't think he said this actually he says i think that main event 100 million years ago is going to be continuing to be a major source of research for the foreseeable future and he says do you know what happened 100 million years ago i don't think you've seen the live streams and i said well yeah that north america plowing into the fixed insular super terrain these are always a bigger story than that and this is a paper by matthews a different matthews i think it's kara matthews at sydney university of sydney in australia 2012. and according to her work at 100 million years ago there was a major plate reorganization in the pacific i don't know any of the data for this but the main message from basil which is second hand from this 2012 paper by matthews if i can find it i'll show it to you but i don't know it's such a mess here with the cat greater than 100 million years ago according to this work major ocean plates were heading south and subducting in the southern hemisphere beneath antarctica let's say and then for some reason a hundred million years ago globally or at least in this pacific basin there was a major about phase and plate started moving north and started subducting in alaska and that's roughly when we set up the time of cooler plate moving north now the timing's off a little bit but basil's basically says would you look a little bit bigger than just off coast of north america there's a major global story 100 million years ago that ultimately might help us understand baja bc and speaking of thinking on large scales you remember bob hildebrand he's he's out there man he says you want baja bc well sure yeah yeah you're going to move all the kielbasa north oh you're not looking big enough you're looking for some major fault in california or something you've got to look in the rockies the major strike slip fault is in the rockies and everything has moved north as far as i can tell bob's the only guy talking that way so there's still creative thinking going on and there's work being done so the older baja bc people who are kind of feeling sad like all that work and all that discussion is all for naught and nobody still really is listening there is new work being done and will we ever get to a major consensus hard to know well is there one piece of evidence that will just completely convince everybody the science moves slowly everybody takes a while to to kind of change their mind if they if they're ever going to change their mind okay that's what i had for you today i don't know how you're feeling uh but i'm not even sure i'm gonna to set up the whole cozy fort i'm just gonna show you some things i think it's dark enough just to do it this way and of course we'll do some live q a as well let's see if this will work without setting up the whole cozy fork because it's already 10 30 as you well know we still have 900 people that is encouraging so i guess battery 100 battery 100 that was my favorite part of friday by the way every 100 battery 100 no you'd think the guy would learn from his mistakes okay i am doing what i'm getting rid of us and this is the video field report from chris in torrance california the video arrived by email last night at about 8 30 and i immediately viewed it and thought this is perfect so good morning my name is chris so chris just happened to make one of these video field reports he picked the polona schist right next to you to interstate 5 outside of los angeles basically in the transverse ranges and it fits perfectly into what we were doing he didn't i don't think i don't think he knew that tie or maybe he did uh this is a little longer than our three minute reports but i'm going to show you the whole thing because it's well done i hope you don't mind okay chris i don't know if you're watching live or not i think i can do it just like this good morning my name is chris florin i'm coming to you from southern california more specifically an area called blue cut which is right on the san andreas fault near interstate 15 at the cajon pass so right behind me right there that is the san andreas fault going away from us in that direction and the road down there is historic route 66 and there's obviously a train tracks with a freight train i'm here basically as part of the challenge to make a geology field report as part of the uh exotic terrain a to z uh sessions that professor nick zetner is live streaming on youtube decided to come out and look at something called the polona schist which is i believe green schist from what i've read you can see some of it behind me here now it's a metamorphic rock it's very blue-green in color um i'm not a geologist i'm a mechanical engineer my work is mostly with race cars so i don't really know what i'm talking about here but i'm enjoying learning about uh geology from professor nick and i realize the reason i like it so much is that uh well you know that feeling that dream that you keep having where you're still in college and you wake up and there's a class that you haven't gone to that you just remembered and you haven't studied and you don't know any of the material and it's the finals right so now you have to go take the final exam but you're not prepared it's a dream that i have uh recurring um even though i've been out of school for years but uh this this series i guess and learning from professor nick is kind of the opposite of that feeling um because i feel like i'm learning i'm having fun and if there were a test i would be prepared but there is no final as far as i know and this is i'm on a big outcrop that's a hillside and i'm in a very dangerous looking uh rocky wash here so i hope there's no flash flood or earthquake um i scrambled up the side of the mountain here so let's get a better idea of what's going on here this is the roadside geology of southern california book that i brought with me by arthur sylvester and elizabeth gans and so just to orient everyone we are down here in the transverse ranges of course there's the peninsula range batholith that we learned about on friday there's the sierra nevada batholith and we are in between along with the mojave desert and the transverse range as far as i know is one of the only east-west trending mountain ranges in the country and it's done that because of some clockwise rotation i guess it used to be more north-south and now a block of crust is rotated which might sound familiar from pacific northwest geology but it's also compressed because we have the pacific plate uh smooshing the north american plate here where the san andreas fault takes a bend and so if we look at this other page here we can see that bend and uh so san andreas fault runs this way and so we're right here in the middle where it bisects the uh transverse ranges at an angle and the shortening zone is i guess the compression of uh the crust here's a really cool relief map showing the san andreas fault very clearly running uh diagonally across the page here and so the polona shist is on this side of the fault the southwestern side the rocks on the other side are completely different so i think it's safe to say this area we're in here probably moved to several hundred miles i don't know how many exactly we've got interstate 15 running north if you ever driven to las vegas from southern california you will know this this stretch of road it goes up a long path called the cajon pass and you can see uh freight trains running on the left as you go up towards the high desert but we're right here i believe uh this little sliver of purple the purple is the polona schist and uh we're on the southwest side of the fault this is lone pine canyon that we looked at before san andreas fault running up to the northwest and you can see there's quite a bit of this polona shift on the southwest side of the fault and cajon creek here takes this big this nice lazy bend because all of this land has been displaced right laterally as far as i understand here's a passage that i really enjoyed uh relating to the san gabriel mountains the entire rock complex is so unique that some authors believe they represent an exotic terrain perhaps a small micro continent added to the north american plate during the subduction of the farallon plate so the big event of 100 million years ago is in there so maybe the polana shift was part of that uh let's take a look more closely at the shift itself it's uh it's got some silly flex on some of the pieces here they're very very shiny metallic flakes i brought along a small hammer it's definitely not a rock hammer it does have a square face i think it's a leather working hammer but let's see if we can get a look inside of one of these guys here there we go it's it's very flaky stuff uh it didn't take much to turn this into many flaky slices here and it doesn't really look all that different on the inside the roadside geology book was saying that this is low-grade metamorphosed i don't exactly understand what that means but maybe it's related to how easily it comes apart and it said also that the current understanding is that this stuff represents what was scraped off of the top of the farallon plate as it subducted under north america i think it was metamorphosed in the cretaceous period don't quote me on that though here's an interesting piece that's really clearly folded at 90 degrees um there's what looks like some quartz in there i see some rust colorations but i think this is still a green schist the palona schist oh man look at this piece super clear striations layers in the rock uh it's sitting vertically but you can see all the different shades of green and some yellow and whiter colors in there but lots and lots of layering so as i understand it schist used to be shale which used to be mud so does that represent mud deposits on the bottom of the shallow sea maybe i don't know so thanks for joining me on this adventure to see the blue cut polona schist [Music] i'll end by looking back across the road here i scrambled down because i was tired of almost falling uh in those loose rocks but i was up in there this is chris florin signing out thanks to professor nick for such an interesting way to spend some time during the pandemic cheers chris that was excellent thank you so much for going out yesterday and doing that like he saw friday's show went out did that yesterday turn 200 sent it last night um we need to visit with daryl cowan i don't know if daryl is still with us in the live chat but you know that daryl has been a big part of this series and i'm grateful to him for so many things here's visiting with daryl and talking about those same rocks and the zircons in the nanaimo just part of um i was going gonna say wake up but kind of you know like um there's something important here and and that's why we i want to set this up a little better so daryl wrote that very famous 1997 paper which was essentially 25 years after merle started the concept and daryl was like look this people aren't believing this thing can i rally some of the geologists who are younger here to go out and use some new techniques including detrital zircons and so in a way the work of will matthews and kristen sauer and some others are a direct follow-through from what daryl was pretty much asking many of the geologists here in the american west to see if we can't find more evidence and we're still not totally convincing everybody but it is nice to see follow-through from a guy like this and this is the university of washington professor since the mid-1970s who has had he's basically advised most of the key workers including john garver who we will feature on friday next darrell we put in i just looked at that this morning four things that you could do and uh provenance studies that means um interesting sidebar here but provenance when you look at a sandstone and you look at the sand grains you want to know where all the minerals came from the provenance of source so we said the provenance of the sandstones and the metal basin that's over east of the cascades and it's got beautiful stratified sedimentary rocks in it and if you study the sand grains you might be able to figure out where were they eroded from next door or somewhere else and the nanaimo which is this fabulous upper cretaceous very thick section in just a little bit in in san juan islands but in the straits of georgia nanaimo beautiful sandstones look at the sand grains and see where they came from did they come from the coast mountains of british columbia or somewhere else and john garver he one of our colleagues at uw joe vance had gotten interested in in dating zircons the mineral zircon which is a detrital mineral little grains of zirconium silicate using a fission track method you know to try to figure out the age of the zircon and john garver was all over this he did this in his master's work and so he might have been the one who said well you know let's let's think about pre-cambrian zircons because in that paper there's a map of pre-cambrian basement in north america of widely divergent ages 2.5 billion up in wyoming 1.4 down in the mojave and we thought wow if you could find zircons in the sand and date them and they're pre-cambrian you might be able to figure out where along them because the the ages range from older in wyoming to the north to younger to the south there you go there's you're kind of um so that's why that's why provenance studying the detrital grains came in and i think there's also one about well can you match rocks um from let's say eastern washington or eastern british columbia right across all these faults and there's a pinpoint you know where you can say hey that rock unit on vancouver island the san juans is so like one over here in in the okanagan valley it can't possibly and to me i agree thanks again daryl so much but i agree that's a big part of what might work with at least general audiences can we find the same freaking rock can we find some rock that's in the north cascades it's identical and look in every way possible in the south and we're getting close to that with this joaquin nice and the polona schist let's say uh more and more of that will i think be a very satisfying way to restore all of this crazy amount of offset okay that's it oh why not one last thing and then we're going to your your live q a quarter to 11. you remember this we don't need sound for this remember this i promise next sunday i i wholeheartedly promise that we will try to take all these things from this fall and put them together and i think i might come back to this this is from karen siegl's research group and the brand new paper from edward clinette one of her students who's now in austin texas this was just his masters apparently i can't believe it but we're starting to see a few new things that we couldn't see before and by we i mean me there's so much to look at here but orange is insular purple is inter montane when's baja bc 85 to 55. let me play this and let's see if you can find can do they include baja bc in their work from the lower mantle in restoring these major terrains let's see obviously they must i wouldn't bother showing it to you 140 130 120. here comes the main event right there underwhelming 85 60. so did you see it we'll replay that part uh i'm curious why they don't start baja bc at 85 seems like it's kind of delayed from their reconstructions again they're taking remember old slabs that went left the earth's surface and went all the way down to the lower mantle and they're trying to bring those back to the surface in ocean basins that are long gone and and even like how do they know about baja bc from the ocean from the lower mantle never thought about that until right now but let's start it at 100 and i'm looking at it backwards but watch orange and purple when does it start moving north like 60 and it's still moving north at like 45 so that seems out of sync with the geology that we know here on land despite saying that i'll have more commentary i think on this and trying to tie it all together a week from today that's enough to you and live comments i've closed our session so i gotta go find it again hang on uh typing nick from home baja bc into the live oh it's live now well that's cool oh there we are okay that was fun i don't think i've ever done that if you're new to us i doubt you are but if you are please type in your question uppercase and i'll try to answer a few of these i don't know if we need these lights now bishop is done screwing around and vinman's bakery in downtown ellensburg washington you gotta love it and thank you popping the live chat out like a boss people are coming back in the house now after being out they were chased out of the house uh but uh it's okay they can handle it maybe you can handle a few uh household sounds bizarre sleeping now uh mr tony how do strike faults go dr strike slip faults go away i'm not sure what you mean um one way to answer that however is to say strike slip faulting is a reaction to major tectonic plates that are not hitting head on or not moving away from each other oblique collision suggests strike slip activity so i would answer your question by saying strike slip faulting stops when you change the plate direction interaction whether it used to be oblique and now it's head on or it used to be oblique and now it's divergent so if that's what you mean by strike slip faults going away that's the answer sober is a hundred million years ago also the time of a magnetic reversal i don't know that i don't know that it seems like if it was i would have heard about it but i don't know steven from the uk could the log jam at the palouse promontory be responsible in part for the clockwise rotation in the northwest thank you steve an interesting question so basil hasn't published this paper yet but he was so kind just in zoom and said yeah i'll send you a pre-print no problem i'll just send you some slides so this is a little bit more on the palouse promontory spurred by stephen's question uh basil said he never dreamt he'd go to the western idaho and start looking at the pre-cambrian margin but there apparently is this very kind of jagged stair-steppy type of uh edge to the north american craton in that area and through the years people have viewed remember antarctica or australia used to be connected to us and then rifted away there's been debate about whether the rift was in that direction or in this direction and that i'm kind of stalling here to be honest because i'm not really sure the answer so i'll stop stalling but you restore this orofino corner up by 30 degrees i already showed you that this is such an old feature i don't see how it can be responsible for the the clockwise rotation that we have today steve it's more conventional for us to view modern plate vectors of the pacific plate and the juan de fuca plate offshore today that's actually the the motor behind the ongoing clockwise rotation we'll talk more about the cooler plate and a few other concepts on friday when we talk about celezia the uh chew gash the yucatan the leech river that's all kind of post baja bc as i understand it today thank you for the question k edmondson okay i see now that i z terrain is too old for this story being deposited on baker terrain which appears to be beneath walla terrain i think more of a statement k than a question but yes if you're in the blue mountains we're definitely not talking about major baja bc action and that's not a major statement to make but reinforced by um basil seeing northern what's he seeing he's seeing action on the western night of hasher zone he's seeing shearing along the western idaho shear zone between 185 but it's not a major baja bc translation as i understand it robert is there continental evidence of a subducted cool affairlance spreading ridge yes much of that's coming next week with celestia but too many papers everywhere you remember the will matthews thing where he showed the mojave breach and he showed the cpc being removed from the rest of the kielbasa that could be considered evidence for the intersection of that spreading ridge and north america but if you mean an actual creation or you're seeing continental evidence i see what you're asking now yes that's coming on friday thank you pat so there is still no evidence separating lem high zircons from mojave depends on who you talk to those are the two camps that are quite entrenched and i don't know enough about the detailed pre-cambrian ages and chemistries but according to the mojave people the mojave is for sure and according to the lemma people it's the alumni for sure so it's one of those where i i don't know i don't know uh roz during a hundred million year event is it possible the magnetic fields flip too okay raz has the same question i'll look into that but i don't i had a geologic time scale here with the magnetic you can just google geologic time scale and if it's a thorough one there's little black and white bar strips along the margin of the geologic time scale just go into google and find a geologic time scale and you can see when the magnetic field flipped just graphically with black white black white normal reverse normal reverse look at 100 million years ago see if there's a change and if there is a change i don't know what it means but two of you have asked about it are there zircons in the plutons yes so these zircons are tiny minerals they're in the kielbasa the zircons are in the granitic material and then as you erode the granitic material you free the zircons out of their batholith prison and they're allowed to flow down the river and then get redeposited or deposited for the first time in a sedimentary basin the nanaimo or the metal did you see that i'm sure i can't find it but there's thought that possibly the metal is a four arc basin for the peninsular ranges basilis and the nanaimo is the forearc basin for the cpc which puts both of those four arc basins way farther to the south lots of new things for me to think about a couple more and i we it's obviously a record all right i think you're all maxed out here these are all more jokes than they are questions tousan thumb wants to ask about the columbia and payment still thinking about that i see i i i need to learn more i don't know much about it i'm sorry i can't include that here i think it's a it's a a younger feature but i really don't know i'm scrolling backwards now crooning revival 365. if lemi's source is correct wouldn't chuck a nut have north american plate zircons 2 because westward drainage wouldn't have changed until the cascade uplift chucking that you may be onto something but i as i you know i'm a slow thinker i think of the chuck and nut and the swak as crumbled crystalline core and the limb high is crumbled pre-cambrian rock that's hundreds of millions of years older so i you may be connecting things that are not in the same time window but if you're ahead of me there with your question i'm sorry i can't follow two more i'm having too much fun and we still have whatever we have yeah more than 800 are still watching i'm just having a lot of fun here okay i should wrap it up though where's celestia i'll have to tune in on friday that's yeah we'll quit so again the plan i know what we're doing for our final two sessions please join us next friday at 2 p.m pacific time our normal time and we will discuss the last exotic terrain to arrive and it's kind of tied to it is tied to our kula farallon spreading ridge story and we will have continental signature of an accreted terrain from a spreading ridge we'll also be up in alaska featuring john garver and daryl collins work that i vaguely have in my head but i need to learn from both of those guys in the coming week that's friday and then i've decided that next sunday there's really nothing new nothing new next sunday our last session session z and i think i'm just going to call it putting it all together and that will be my attempt to take the lower mantle and the insular and the intermontane in baja bc and basically try to demonstrate what we know and what we still don't know or where the major questions are and what we do think we have data wise to hang our hats on a toast to you thanks again to vinman's bakery for a second custom-made fruitcake i don't believe they're selling these except for possibly a few slices if jeff is still in the comments maybe he can say something about these amazing fruitcakes i forgot to toast you here's to you for joining us today here's another toast to you for taking time out of this busy time of the year for many of us there's lots going on even though we're in this weird pandemic time there's still much going on online shopping uh all sorts of activities that normally happen this time of the year and you've taken time out from all of that to join us for a marathon session this morning and i'm grateful to you so thank you for joining us another toast to you this has been a positive place and i notice when i watch these in replay how positive you are to each other how positive you are when somebody contributes to the show and you make them feel good by kind of affirming their efforts and that's a great thing to be doing during this time most everybody's on edge i was on edge on friday mostly because of the technology but we need less of an edge if possible all over the world here's to us thanks for tuning in this is the end you made it to the end of our marathon session on the latest activity with baja bc research hope that you're introduced excited possibly wanting to learn more on your own terrible grammar to end the live stream but i guess that just happened thank you i love you and goodbye you

Channel: Nick Zentner

Views: 18,811

Rating: 4.9786325 out of 5

Keywords: Nick Zentner, Baja BC, Baja--BC, Exotic Terranes, North Cascades, Nanaimo Group, Myrl Beck

Id: XMUHKcFf2kQ

Length: 142min 34sec (8554 seconds)

Published: Sun Dec 06 2020