Floods of Lava and Water

floods of lava and water here's the opening statement Eastern Washington geology is a unique place and its unique for two reasons we had floods of lava roughly 15 million years ago and we had floods of water during the Ice Age 15,000 years ago that's a very simple nice tidy statement and like most things in this science it's not that simple way more going on but that's the main thing that we want to get across to you tonight most of you know much of this but I'm hoping to add twists and turns here along the way so let's start with a map of Washington and I think I'll try to keep track of some of the stuff we're talking here as well so floods of lava 15 million years ago floods of water 15,000 years ago much less than 1 million years ago all right when people hear that Eastern Washington is full of lavas and if they don't know much geology I think they do their own little math and they think ok well there's lavas and we have volcanoes in Washington we have we have the Cascades that we were talking about last week right so they do their math and they go ok well yeah that's kind of interesting there's a bunch of lavas out there in Eastern Washington they must be related to Mount Rainier not Adams and that sort of thing no that doesn't work at all for sure not absolutely not and the reason is chemistry Magma's around the world in other words lava flows around the world have different chemistry's and the thing that we focus on with the Magma's chemistry that's most indicative of their physical properties is something called silica which is a combination of two elements that the earth is loaded with silicon and oxygen so silicon and oxygen together is silica and we have a magma that is 45% silica it's very runny if we have a magma with up to 75% silica it's very very sticky it's very stiff so the reason I bring this up is that the Magma's that come out of the ground and erupt in the Cascade corridor the whole whack Amole story we were talking about last week those are 60% Magnus those are relatively stiff Magma's and that's why the lava flows did not come out of Rainier and start flowing all the way to the ocean in fact they didn't leave the National Park those are andesite lava flows primarily but there's some de sites and Rio de sites things like that the basalt excuse me the lava flows I gave it I give the punchline away the lava flows in Eastern Washington are not sixty percent they're 45 percent and the rule is to lower the silica the lower the viscosity in other words the more runny the material is so what is 45 percent lava look like when it comes to the surface so if here is a person innocently walking around and suddenly he realizes he's on top of a big active magma chamber and there is 45 percent silica magma that's the runny aspossible love we have in nature and so if that person is stubborn and refuses to leave he is going to be harmed because this is lava flows that are flowing very easily across the surface the first major point then tonight we have lavas in Eastern Washington the chemistry does not match the Cascades so the lavas did not come from the Cascades where did the lavas come from the lavas came from a series of cracks we call these cracks fissures and the fissures are located in extreme South Eastern Washington tonight we're going to focus on the fissures and talk about potential ideas for why those fissures are there because 17 million years ago a little earlier than 1517 million years ago these cracks mysteriously appeared and they weren't minor structures coming out of these fissures in other words these fishes literally retention elack's so they literally opened up and coming from these fissures were unimaginable volumes of magma and because of the low silica content the magma started cooking started traveling started going County to County to County and ultimately many of these lava flows literally made it to the Pacific Ocean so most of the attention is given to the pit salts themselves and we want to start with some basic observations of that but what I really want to do with the basalt part of this and that's how we get into some plate discussion is try to figure out why 17 million years ago why cracks why cracks emitting basalt by the way if you know about the globe basalt is an oceanic lava where do you find this runny 45% silica lava you find it in Iceland you find it in the Galapagos you find it in Hawaii you find it in purely oceanic settings and yet we have these oceanic lavas coming out of our cracks here it's a mystery and I'm not presenting it as a mystery just for us it's still a mystery we're not going to solve it tonight I got to admit that and and some students are very bothered by that we're doing all this work we're doing all this talking and drawing and note-taking and then we don't even know the real answer so I have to say that up front and like we do lots of times with our gatherings here I like to model where the scientific community is and realize there's always work to be done in the future so that's where we're headed let me give you a little bit more basic stuff though about these lava flows more than 300 of them I suppose I had to draw more than 300 of them came out of those cracks and I'll show you plenty of photographs coming down the road for instance if you go over to Vantage and you cross the Columbia River stand at the ginkgo Petrified Forest visitor center there and look at the nice beautiful display and look across the river you see these steps right each of these is a separate line flow and we never really do see all 300 lava flows at one time that's it that's a concept that's difficult we have lava flows crossing the state but the depth is enormous if you take the stack of lava flows and realize how much quantity we're talking about how much mass we're talking about in most cases this basaltic region is more than 2 miles deep the drilling for oil and natural gas recently has shown us that we go 10,000 feet into the earth in this volcanic province and we're still in basalt well what's the elevation of the tri-cities less than a thousand feet right above sea level and yet there's 10,000 vertical feet of basalt so we're below sea level by a long margin with these lavas themselves each flow is the height of this building on average so if we go to Hawaii a place where we can can understand how this process works it's the right chemistry it's the right physical properties that is a small scale but the Hawaiian lava flow is our knee high and travel just a couple of miles these individual flows are 40 feet high and travel 300 miles the scale is way off the charts interestingly and I'm just setting you up now for our plate discussion the magma content truly is 45% silica in other words it's pure oceanic magma coming to the surface here and that's a big point because lots of times when you have magma forming beneath a continent and you have the magma getting to the surface and erupting usually the magma is contaminated on its rise in other words beneath the Cascades there's originally 45 percent silica magma we're pretty sure but by the time that 45 percent silica magma gets to the surface and erupts out of Mount Adams it's 60% because it's taking blocks of continental crust which have lots of silica melting the continental crust were basically contaminating the magma changing the chemistry so that by the time it gets to the surface it's stiff not so with this stuff it's coming from depth we believe but it gets to the surface and it still is pure as it was when it was at the base of the continent so what am I really trying to do I'm trying to get you to think I'm trying to get you to creatively think about ways to explain this bizarre set of circumstances and if we had three hours we'd open it up and we'd have all sorts of different ideas from you and we might get that when the question-and-answer session comes around but what I want to do just for times sake is once we lay this out share some of the ideas that are out there in research groups to try to explain what we have okay so many of you have heard this before lots of basalt vertically lots of basalt laterally a repetitive sequence let's break some new ground that's a pretty simple picture we're now realizing that these cracks did not all form at the same place at the same time so the plot thickens not the lava the lava does not thicken the plot thickens I've got some images a little bit later on to show you this this is pretty new information in the last five years there's a couple guys who have found fissures down in Southern Oregon that are truly seventeen million years then slightly younger fissures in northeastern Oregon slightly younger fissures in southeastern Washington slightly younger fissures even into Central Washington so we have to explain that not only that the fissures are forming but that they are migrating north or these cracks are opening in sequence and essentially zipping to the north we've got issues there I'm pausing because it seems like I can set this up a little more creatively and and I don't want to do that so here's what I have to do now okay okay you want to hear secret I got home you do I can't I came home at 4:30 today and I was tired and and supper was not ready and so I I laid down and I fell asleep and at 45 minutes later supper was ready and the food tasted really good and I'm still kind of sleepy but I promise to fully wake up before we're done in fact yeah I just promised that okay in front of God and everybody I just promised that that a thoroughly wide-awake person my hair is still a little not right but we'll get that all going just just perfectly here some of us know a fair amount of about plate tectonics of Western North America others not so much how are we going to do this let me give you a basic crash course and then we'll go back to these fissures and try to explain them and ultimately bring them in living color here in just a bit quick plate map familiar to many oh I should do that in a different color so veterans of this series know that that's Washington Oregon and California new people are like how'd you know that well we've been around we know what we're doing so we have a beautiful small oceanic plate off the shore of Washington in Oregon called the Juan de Fuca plate in a different color we have further to the south a different plate moving Northwest the Pacific plate and in the third color we have all of this part of North American continent moving to the southwest slightly the west southwest the North American plate we have in past lectures this fall looked at evidence for how we know this is happening how we know this is happening how we know this is happening we have measurements now using the GPS network to document this beautifully we also have geologic evidence and this is review from a couple of weeks ago we have a hot spot underneath Yellowstone National Parks which is here and trailing away from Yellowstone is a vast volcanic province called the Snake River plain that stretches across the other night at home and if we look at the age of volcanic rock on the Snake River plain the rock gets progressively older so hang with me in Yellowstone Park itself they'll still do this in red less than a million years old just north of Pocatello about five million years old between Boise and Twin Falls about ten million years old getting down into northern Nevada about 15 million years old are you thinking eventually we run out of the Snake River plain we run out of this volcanic path and guess what the age of the oldest volcanic material is in this swath 17 million years now let's put on this map those guys which are in the neighborhood of 17 million years old which have produced our Columbia River basalts ield flooding Eastern Washington some of those flows getting to the Oregon coast now up until two years ago in my geology of national parks class we would talk about the results of Eastern Washington even though there's not a national park there we talk about Yellowstone Park and talk about the hotspot tract and we realize that the timing of this hotspot tract and Yellowstone and the timing of this the fissures of the Columbia River basalts ield we realized the timing was next door to each other but we couldn't quite see a connection a physical connection between what's going on here and what's going on here until that migration of fissures that I just quickly mentioned here that stuff that came out Vivek camp from San Diego State in the last two years so let me plot that on these fissures didn't all form right here 17 million years ago the fissures 17 million years ago formed in southeastern Oregon slightly younger slightly younger and by the time we get up into the fissures of Central Washington we're to about fourteen million so there's a three million year transition time between the fissures right down here by the beginning of this hotspot tract and what's going on here so here is a quick actually you know what I'm feeling experimental remember this gesture I'm feeling this who's got some ideas suddenly this is an anatomy and physiology class would you care to elaborate hands down here yes okay so I'll take kernels of these contributions and kind of run with them if you don't mind so we've learned way back that we have terrains that have come in off the Pacific Ocean remember this pieces of crust that were made elsewhere and added to the edge of North America including Mount Stewart and there's a very clear boundary between where we had old-fashioned North America that was not terrains and these pieces of things that came in that boundary between the stuff that came in and old-fashioned North America is write down our Fisher's own is there a connection this history of the terrains coming in I'm going to list these and then go back to the list and ding each one of them because again we don't believe any of these wholeheartedly there's problems with every one of these ideas different approach yes give it a try Marty right yep okay so marty is talking about kind of the same thing here that there was a time where Washington didn't exist who Oregon did not exist and it was deep ocean water here and Marty's saying well we had a deep ocean history here so is it that surprising we have all this oceanic lava that doesn't work it's good I see the logic but it doesn't work because the dates are not supporting you all of Washington has been assembled all of Oregon has been assembled by 50 million years ago this is much younger than that so we have brought everybody in so we're wondering if it's related to rains because we realized the Washington organ have been assembled but we're still wondering about that old boundary between terrain and Old North America let's keep it going here yes ma'am yeah are you thinking the crust is thinner here or are you seeing something else okay so here's here's here's a great example that I would take a kernel of what a suggestion was and just run with it so I'm going to put words in your mouth now you're ready not even close to what you wanted to say here but I like the initial thought and I appreciate you for that that's what you meant right meteorite there's a roadside geology series have you seen them they have yellow covers roadsides geology of Washington of Oregon etc they're all written by a couple of guys from University of Montana their pet theory is that a meteorite a piece of extraterrestrial material flew through space and 17 million years ago struck North America right here and wounded the crust and was a severe enough impact that flood basalts started coming up at the point of impact and literally flooded the crater in any evidence that we would want for that to happen so there is question about the thickness of the crust here is it unusually thin unusually thick and there's geophysical data that's not conclusive it seems to me from this particular area so I twisted that a bit sorry about that yeah good let's use that thank you for that two three lectures ago we talked about a clockwise rotation that is currently going on in the Pacific Northwest GPS stations showing us that this is real and our earthquakes in the Pacific Northwest are a direct result of this clockwise rotation this gentleman is bringing this up because I didn't draw these arrows very well the thought is and again I'm putting words in your mouth if we're rotating the crust we're rotating it away from something that probably is being extended right if we're pulling this block away from the Rocky Mountains generally what's happening behind that clockwise rotation is that helping us understand these cracks another approach what's the Juan de Fuca plate doing what's generally the one if you could play doing its subducting is it possible is it possible that these lavas coming out of these cracks are related to the subduction of the Juan de Fuca plate we know that the one if you could play this abducting to make the Cascades what would we have to do to the Juan de Fuca plate itself to have it not feed the Cascades for a while and feed these fissures what would be different about the one if you could plate itself speed it up but we could we could also play with the angle of subduction in other words here's it there's a different diagram unrelated to what we're doing here if we have subduction that is steep we're going to feed volcanoes there if we then decide that we're going to shallow the angle of subduction suddenly our volcanoes are going to be further inland you see that rationale so possibly seventeen million years ago the one to Fuca plate was not subducting as steeply and was gently subducting more gently and the result was this volcanism further inland anybody else got a crazy idea before we go how would that well okay okay ray is wondering ultimately about a connection with the Yellowstone hotspot and we haven't learned much about hot spots but let me try it quickly hot spots are fixed stationary sources of heat from deep in the earth think of it like a big blowtorch that in a welder shop okay just get your goggles on acetylene blowtorch okay so let's hold that torch steady that's our hot spot where the hot spot is in contact with a plate it's going to make a volcano it's going to make an active volcanic scene now if the plate is not moving we're going to have nothing but an erupting volcano at this knuckle of my hand but if we slowly are moving our plate over this stationary hotspot we're going to get a trail of volcanic lavas and the aged pattern of that trail is going to be apparent in other words we're going to have brand-new lavas here now if we start moving the plate we're going to get younger and younger lavas as we trail off in this direction so ray knows that North America is moving in this direction why because he actually sees the arrow in the labeling good job and he knows that as we drag over the stationary hot spot we're going to get this whole tract of material the main point is where was the hot spot located 17 million years ago it wasn't in Wyoming the hot spot was right here so we're wondering about these fissures the fissures are forming starting down here about 17 million years okay there might be other ideas but I'm going to I'm going to I'm going to move on thank you for that contribution that was fun problems with each of these the terrain boundary is here in other words the boundary between terrains and old-fashion north america but there's no sign that that's an active region and there's no geophysical idea that there's any sort of space or any sort of magma that has dealt with this boundary in fact we don't find any young lavas or even lavas from 17 million years at other places along the boundary so there's just not enough good physical evidence to think that that boundary has anything really strongly supporting this evidence for the meteorite impact too just to say it's all buried beneath the basalt isn't quite good enough is it - really wholeheartedly believe it an idea we need to have a lot of different kinds of evidence all pointed the same conclusion the rotation idea I agree that we have rotation I agree we have extension behind here's something I didn't mention before but implied I think these fissures are no longer active in fact these fissures have not produced ones drop of lava in the last six million years and really it's been quiet for twelve million years so if this rotation is part of it why we have these fissures why don't we still have basaltic volcanism in Eastern Washington the rotation is current in other words and yet we don't have activity with the fissures themselves subduction related kind of a nice idea flatten out the subduction feed these volcanoes but our opening statement was the Cascades have 60% silica these volcanoes were trying to explain how 45 and generally when you subducting crust beneath continental crust you get 60% silica magma so these are the wrong of volcanoes coming out of these fissures having them being related to subduction I'm a guy that likes number five and I'll expand on this idea when we get to the slides but the general consensus right now is that when the hotspot began and that's a whole nother discussion why did the hotspot start 17 million years ago why didn't this snake of a prank thing continue all the way to the coast for instance it doesn't it abruptly stops this volcanic age progression stops in Northern Nevada 17 million years ago okay let's take that at face value when this thing started there was a broad regional head to the hotspot in other words when it started it didn't have its act together and so there's a regional scene of volcanism 17 million years ago and then as North America starts moving over it we kind of concentrate the torch a little bit and narrow the gauge of the torch so that we're actually carving a very very clear picture here there's more on that coming in a second even that has problems gyah physically and I don't know much about geophysics but people have been running seismic surveys through the Snake River plain looking at what's going on at depth in the crust and they're not seeing significant patterns of a hot spot coming through I can't giving you more than that because I don't know much about that what I do know about is field geology and I'll bet you less than five people in the room know this right here I don't know much about it myself from this area in northern Nevada where the Yellowstone hotspot began is this beautiful young of lava towards Yellowstone Park we get that with the stationary hotspot and a moving North American plate researchers mainly at Oregon State University have now found a mirror youngin of lavas towards Bend 17 - young I don't know about zero but young let's let's say five how do you explain that if you like a stationary hotspot and a moving plate that works beautifully this appears to be disagreeing with that if you're a regional hotspot head person and then have movement rippling away not only the fissures are moving away but the rocks themselves are moving away that's a whole nother elaborate story so I have some diagrams coming in a bit to add to that okay we're setting up the images on top of all of that coming fifteen thousand years ago is a story that is familiar to some and not so much to others so I'm going to do it quickly Ice Age flood story in ten minutes ready oh we've we've spent hours in the field with many of you evening lectures up on campus endless discussion ten minutes okay so this is geared for people who have never heard this story and if you have heard the story maybe I can toss in a couple new things for you Washington Oregon Idaho Montana let's put in Ellensburg and Seattle and Spokane and Portland and Missoula so this story takes place less than 1 million years ago hovering around 15,000 years ago although it's clear now that there were multiple floods across Eastern Washington and they have many ages hovering around 15,000 but that's that's the rough ballpark this is a time when we still have ice on this map we have an ice sheet in fact that 15,000 years ago is slowly starting to melt and is still melting today it's on Greenland now but it was once that ice sheet was once large enough to be into the Northwest here so this is a retreating ice sheet 15,000 years ago a melting ice sheet with a lot of meltwater coming off the front of the ice now normally there's not much of a story because the ice the water coming off the ice drains to the ocean and nobody writes anything up but there were a couple of lobes of ice that played a part in our drama here a lobe of ice like an earlobe is a little bit further south than its neighbors so this is the Okanagan lobe which some of us saw in September up on the Waterville plateau we didn't see the ice but we saw the evidence for it the Purcell lobe which came down toward Sand Point and Lake Pend Oreille in the panhandle of Idaho this is the key part of the story meltwater coming off the front of the ice in Montana was trapped was not allowed to drain to the ocean because of this ice dam so there was a temporary Lake present-day Missoula Montana significant amount of water filling many of the valleys of western Montana could not get to the ocean where it needs to go because this glacier was blocking the outlet finally we get enough water in the lake where we breached the dam and the water dramatically crosses Eastern Washington in individual flow fields in other words it wasn't the big continuous wall of water thundering across eastern Washington landscape and said it was individual fingers of floodwater and in between those fingers of floodwater completely untouched by the floods so one really interesting thing about the landforms of Eastern Washington is and you'll see this with the images you can easily see if you look for it where the floodwaters hit but also where they missed and where the floodwaters missed is incredibly graceful delicate landforms think the Palouse Hills Hills made out of kitchen flour basically that would have been swept away at an instant if it got hit by the floods but yet those very graceful hills are still intact between the floodwaters there was a ridge there is a ridge between Ellensburg and Vantage and that Ridge saved Ellensburg from these floods we did not get any Ice Age floods in Kittitas Valley because of the ridge up at whiskey-dick with all the wind turbines now ryegrass summit you know what I'm talking so we have dramatic flood evidence on the Vantage side of that Ridge we have no flava evidence on the Ellensburg side ultimately that floodwater is all trying to get to the ocean now it's happy water now it has gotten away from glacial lake Missoula it's traveling up to 50 miles an hour across the the openness of Eastern Washington but it's not a nice clear shot to the ocean there are some constrictions to deal with this is a recent enough story that the ridges that we know the opening to the Columbia River Gorge that we know were pretty much the way they were then as they are now so we'll Lula Gap down by the tri-cities was a problem the entrance to the Columbia River Gorge was a problem for this water and by problem I mean it couldn't maintain its 50 miles an hour speed all the way to the ocean it had to slow down and the water had to wait it's turn to squeeze through some of these bottlenecks as it slowed down stuff it was carrying started to drop so we have not only scars where the floods were taking material away but we also have all through Eastern Washington places where the stuff that the floods picked up were dropped most obviously big boulders out in the middle of a field show you photos but less obviously fine grain layers of flood deposit that we're only being deposited where we had more lake formation so much of the water that cruised across the eastern Washington and picked up material dropped much that material with the second lake that formed as the water was waiting by tri-cities so this is glacial lake Missoula this is glacial Lake Louis which backed up into the Quincy Basin backed up in many places that we have here in South Central Washington there's a third glacial lake if you really want to dig deep up here AB up stream of the Okanagan ice lobe we have another ponding of water glacial Lake Columbia that also has Lake deposits and feeds into at times Moses Cooley where some of us were this past weekend so this is not particularly helpful that's why I have the images but the story eventually we finally get rid of all of this water it goes out to sea and the debate now is not did the floods happen everyone in science is fine with that and the debate now is not was there one or two floods the debate now is how many floods were there and we have people that believe there are up to a hundred floods a hundred separate Lake glacial lake Mozilla's a hundred separate big bursts of fast-moving water across Eastern Washington that's the next challenge and we have researchers working on this to try to continue to figure out the details of the story there was one flood of a glacial lake that was in the Salt Lake City area in Utah that ponded up water along the Wasatch Front flooding and burying present-day Salt Lake City and eventually there was enough water in that Lake to drain north into southern Idaho and have all of that water follow the Snake River which was a canyon at the time and have that water come up into Washington basically follow the snake most of its course and have flood water squeeze through Hells Canyon and get into our Columbia finally and have Bonneville floodwaters coming down the Columbia River Gorge between Oregon and Washington that was 15,000 years ago one flood one shot 15,000 so we have some Missoula floods that were a little bit older than the Bonneville we have some Missoula floods that were younger than the Bonneville and in some cases especially in Hell's Canyon you can find both flood deposits in the same spot and Missoula are sitting on top of Bonneville okay chase let's hit the Lights many of these photos featured tonight are from a guy named Tom Foster who grew up in town son of Barbara and John Foster John was a communications professor Tom actually was the reason we started the Ellensburg chapter of the Ice Age floods he works for twin city foods and got real interested in this story and he has a gift for photography so I want to share many of his images because his images show not only the basalt but the ice age star stories as well Tom now works in Pasco but it's still involved and has created a beautiful website if you haven't seen it yet I'll probably send a link to that next time around okay so lava flows first 1 2 3 4 5 6 7 8 8 lava flows here just in this particular picture but that's not the whole stack right 300 altogether next one Bryce if I call you Eric don't be offended ok great so Ellensburg is here here's our beautiful map showing the distribution of the basalts that are dominating Eastern Washington if you believe this guy Vic in the last three years we're going to extend this brown down into Northern Nevada and help us connect this with the track of the Yellowstone hotspot next one buddy these are some of the fissures the cracks that have been mapped found that have fed our lava so this is from Vic last year and so he's showing the Columbia River basalts ield literally extending down to Northern Nevada next one these are what we want to visualize then for the fissures for the cracks that are feeding all of this lava next one Bryce this is 7 million years ago oh my god we've got a Fisher forming and we have low viscosity magma coming to the surface and we don't want to visualize a Hawaii volcano we want to visualize a Fisher style eruption with a long line of lava coming out eventually that cools hardens everybody's fine wait a few thousand years for the next one so these eruptions are not every day of the week there are clearly thousands of years of quiet between eruptions but for whatever reason we have another eruption maybe we completely evacuate the magma chamber maybe there's so much magma coming to the surface that it takes a while to replenish the plumbing system but we eventually get another scene and notice what we're doing to the topography what was rugged is now a little bit more flat right we're creating a flat landscape I'm not happy with the focus there so I'm going to let this thing keep going there's debate about how long each flow last we're probably talking about days to maybe a couple of weeks Marty that's the conventional thought okay this is going to get good now we flattened the landscape enough so that the succeeding lava flows have the ability to really cover some ground excuse me and those are the Grande Ronde lava flows some recent photos from tom some of these locations I do not know I believe this is still Palouse Canyon downstream of Palouse Falls on the way to Pullman next one - I can't emphasize enough these landscapes are from - freak shows right the freaks of lava which don't happen very many places in the world and the freaks of Ice Age floodwater what are the odds to have both of these hammer the same area that's why this is such a unique place next one oh pretty picture Wow ah wonderful nothing to do with geology next one look at Washington now so rugged topography in the Cascades and in the Okanagan oh my goodness has it always been like this no the flood love is themselves have filled the low spots and flooded the landscape literally with lava to create a horizontal landscape next one so you know there's scene / advantage next one you know this scene at the Gorge Amphitheatre I'm sure you all go to rock and roll shows over there to see Soundgarden last time while they were great and above the tour bus still three separate lava flows next one we all know this south of town still these guys these are some lava flow this is half way in their journey think of this now those lava flows in our Canyon are halfway between where they came out and the ocean these are Grand Ronde lava flows spectacular next one more spectacular shots from Tom Foster we all know that some of these lava flows naturally form columns and those are cooling structures next one beautiful repetitive columns but as you get to know these lava flows they're just like old friends they don't all have the same ability to form columns some form beautiful columns like the Roza flow others don't form columns at all that's a debatable topic as well next one ooh yes aha are they really farming at an angle no tom has just had an inspirational moment next one thicker this is the Rosa flow which was first described by Rosa dam here in the Yakima River Canyon you know where this is perhaps this is over in Frenchmen Springs Coulee on the Grant County side next one this is the Yakima River Canyon next one don't know where this is but I like it next one on top of a lava flow looking at our beautiful polygonal cracks next one and I can't tell you how many times I've been out with people and we look at particular geometries of columns that aren't perfectly vertical and it's frustrating for me because I don't have an answer why why are these so squirrely I don't know next question Babcock bench near ancient Lakes next one those that were with us a couple days ago and Moses Cooley recognized this this is the Billingsley ranch at the head of Moses Coulee one two three flows here vesicles at the top pillows at the base sometimes more coming on that in just a sec next one you've been to the Columbia River at the Vantage Area let's cross the bridge next one here is route 26 so Vantage is off to the left we're going to go we're going to go to Royal City we're going to get on 26 and climb out of the Columbia Gorge and this is one lava flow here's another next one Bryce this is the flow top and this orange e junk at the bottom tells us something about what the land was like when this lava flow came in next one look at the scale of this orange e stuff so here's a semi coming from Royal heading to Vantage again our flow top is here and you know almost a quarter of the lava flow is this orange material what it next one their pillow structures that's our name for them it's the orange e material is actually obsidian you know volcanic glass it was a this orange stuff was originally volcanic glass but has broken down or crumbled through time D vitrified we call it and this the brown circles where our interpretation our fingers of lava that went out into water so the punchline here is when you see pillows like this or a pillow structure at the base of a lava flow you know that the lava flow was fighting water as it was crossing the state probably a temporary lake next one how do we know this well off the coast of Hawaii we've looked at what lava flows do when they leave the island and go into the Pacific they they kind of freak out into these little pillowy wormy things so this is lava going out into the Pacific and we're getting these shells forming with this lava coming behind it and to us that's what happens anytime you have lava going into water think of the contrast in temperatures there next one please so each of these guys is one of those fingers it's not really a circle it's not really a ball it's a tube and again this was glass where the lava was getting chilled instantly by the water itself next one please oh car queues for scale very very fine detail there's even some little gas bubbles in here to give us a feeling for the drama next one okay I think we're moving to the plate discussion now seemed like that was where our energy was highest next one oh not quite yet can you go back Bryce let's test your skills now you're young good we're to the edge of this flow field so we can not only teach the salt geology here at Central Washington University we can also teach stuff out of the basalt field where technically is that northern edge of the basalts the answer is Bryce Table Mountain so on a beautiful clear day it's obvious to anybody who cares to look at this up at Lion Rock that's the end of the line for our beautiful consistent Columbia River basalts a basalt lava flows and once we get north of Table Mountain we're in two significant the older rock in fact yes we're into the old terrain story with Mount Stewart and the paleomagnetism and all that jazz that's much much older 15 million 93 million so let me give you some professional diagrams again from the guy who is a hotspot man so he likes this idea of the migrating away from the hotspot story let's see if this works for you hey check it out Snake River plain Yellowstone we know the significance of that now right these are the earliest of the basalt that came out of the fissure 17 million years ago next one the basalt flows themselves migrate north next one younger lavas next one younger lavas there's ages up here we're all still in the neighborhood of 15 million years ago next one we're starting to flood Ellensburg now next one so those youngest lava flows were kind of wimpy they didn't have much energy left so we saw that transition from south to north of the flows themselves that must mean that the fissures are also migrating with that's the next set of images go ahead Bryce the dikes or feeder dikes feeding the Steen's next one in Naha next one Grande Ronde look at these guys they're working their way north as we get younger our model needs to explain this the best we can that's basically a vote for hot spot related although if you love your contribution don't give up just keep cool yeah but but but my idea was the best and here's why and I can explain it okay we can do that over beer later on next one aha so circular features to add to the problem these circular features are calderas from explosive volcanism so of course our lavas are passive and flood without drama the Yellowstone hotspot story is one tied with drama death explosion and the point is these calderas young as we get to Yellowstone Park and if you've been across the other night at home and you don't remember seeing these it's ok they're not at the surface they're buried by younger lava flows like it creators of the Moon or places along the Snake River Canyon so to summarize the hot spot people initial hot spot activity and then let's migrate here's a twist not only our way but early indications that there's young inge lavas and fissures south and maybe even towards Bend which is we're going to do next here we go next one please so here's taking all the stuff off the map and just showing Yellowstone Snake River plain cutting right across these mountain ranges that was my master's thesis project by the way back in the dark ages here's Kittitas Valley and so we're on the map and potentially connected to this story this is an interesting pattern isn't it these are the mountains and valleys of Nevada part of something called the Basin and Range province which is potentially related to this as well next one please so just a couple from this surprising new development actually in the last ten years from Oregon I'll give you a few diagrams that I grabbed off the internet that basically try to say the same thing if you look at solicit volcanism a meaning not the results but the sticky explosive lavas that are in eastern oregon which is great country by the way i don't know if you spend much time in eastern oregon but it's remote and beautiful and the geology is right there in your face ten eight six four one Newberry volcano that's the young of the sticky relights in Eastern Oregon that really shouldn't be happening if you're a simple Yellowstone hotspot person because the plate is moving to the southwest doesn't make sense to have this if that's all that's going on next one same message showing both the youngin of the lavas as we go towards Yellowstone and the youngin of the lavas as we go towards Newberry volcano by bend what is going on I don't know next one yeah just just an inventory of lavas over the last in the 17 million years in the northwest not only by age but by by rock type let's not worry about it I don't know what's going on here okay so somebody's trying to explain all this somebody's trying to model I think this person likes the wonder if you could plate subducting as part of the story and sending some melting to the base the point is people are trying to be pretty damn creative to come up with an explanation for the high lava Plains what we're talking about and the mirror track which most people feel pretty good about the Snake River plain fascinating stuff if you ask me but I'm biased oh here so if you're still with it you want a hot spot and a moving North American plate this should feel good to you hot spot Springs galore by the way that this is current heat yes next one just to point out that our fissures here are inland of our cascade volcanoes from last week subduction related for these guys we really can't connect the subduction with our fissures we need an independent source whether that's a hotspot or clockwise rotation or meteorite haha all those things as possibilities so to Yellowstone Park quickly just to remind ourselves that's where the hotspot is currently located next one we know know where Yellowstone is it's in Wyoming so currently in Yellowstone there is a caldera from the last explosion which was 600,000 years ago it's been 600,000 years in the last three explosions deforming calderas have been every six hundred thousand years so there's another one of these cycles and it looks like if the pattern is holding true we might be in for some interesting action down the road but probably not in our lifetime next one Yellowstone Park and the Snake River plain keep going we've got about five minutes left of this stuff if you can hang in here's the stationery hotspot and the moving North American plate these are centimetres per year so the North American plates moving roughly three centimeters a year over the hotspot we talked about that a couple weeks ago the movement of the Pacific plate over the Hawaiian hotspot three times as fast so the spreading of the East Pacific Rise is three times as fast as the spreading of the mid-atlantic ridge there are other hotspots around the world we don't own we don't patent hotspots there are other places in the world less known of them at least for me as a biased American next one so the hotspot has created not only the Hawaiian Islands same idea in Hawaii then as you get away from the hotspot the volcanic material is going to get older but if you chuck out the water the Pacific Ocean you realize that that trail goes all the way to Russia next one and as the volcanoes get moved off the hotspot they quit erupting and slowly die and eventually get reduced to a seamount which is a mountain under water a little animation of that let's try it for fun so stationary hotspot this can work for Yellowstone or Hawaii is this what you had in mind stationary heat source moving plate only one active volcano at a time and the deposits are going to get progressively older as we go down plate direction the only thing we'd add to this picture for Yellowstone is we'd have thicker crust would get rid of the water and we'd have explosions instead of quiet shield volcano building and here's our calderas in millions of years getting progressively older until we get down to the end of the line next one image from space check out this beautiful scar and then this is a younger feature that does not appear to be part of our story even though it's tempting to use it next one how can you go back for a sec did you look in here look at how unusual we are for the American West we've basically loaded the crust with those lavas and depressed the crust our elevations are low look at the Weather Channel we're a little bit warmer than everybody else right because of those basalts depressing our crust okay quickly some images to put little frosting on the cake very recent geology and then we'll quit an image 15,000 years ago of the Puget lobe the Okanagan lobe the Purcell lobe glacial lake Missoula glacial Lake Columbia if you can see the fine blue and glacier Lake Lewis is not on the map but when it was full of water filling areas by Pasco next one here's a quick synopsis then when we finally break the Purcell lobe the water is cruising across the eastern Washington heading for will ulla gap and scouring the landscape upstream of that next one satellite images from NASA where you can see the flow paths the scale of these ice age floods are best viewed from that distance it's like a braided stream channel in Alaska next one these are also from this space shuttle or something like that something up in space next one a little dark can you can you see where the flood waters happened here's Grand Coulee here's Moses Coulee here's a saddle mountains next one Wow gaudy images I have same idea flood paths next one I love these images I've showed them to you before a little bit just spectacular showing where the floods hit and where they missed notice how Kittitas County looks so different than this mainly because we were not hammered by the floods next one Moses Cooley if you were with us on Sunday next one you got to really know Eastern Washington loved it to know some of these towns oh yeah out by Wilbur oh yeah I got you I know where you are really next one wash talk no sure yeah good people they're back at Ground Zero where the waters are cumulating there's actually shorelines from that ancient glacial lake Missoula next one Tom Foster photo campus of University of Montana there's the Big M on the hillside and by god we've got ancient shorelines of that Lake there's murmuring in the crowd I'll take that as a good sign next one interesting thought and when I first came to Ellensburg I didn't really believe or understand that the floods ripped up so much rock I just didn't get it I get that the floods happen but wouldn't they just polish the surface why are you literally creating a Coulee from scratch and then I started learning more about the basalt and the heavily fractured nature of the song The Rock is pre-cut essentially it's ready to be hauled off and what if Eastern Washington was all granite I don't think we'd have the coolies that we know I don't think we'd have all these chasms all these gashes in the landscape I do think the flood water would just cruise over the surface so it's a combination that's what we're trying to do tonight realizing it's this magical combination of these lavas and the floods to create this dramatic plucking the rock away from the countryside next one please right so we're looking at the details of these cooling structures next one we can see the granite doesn't really have that next one and so the rest are just spectacular photos from Tom look at these walls my god and the reason is the waters conclude through there and just pull those columns away haul them away easy work next one next you know where that is it's not it's Frenchman Springs cooling so here's the old Vantage highway we're heading west on the Vantage highway used to be able to cross the river and then head towards Ellensburg on the Vantage highway this is Frenchman Springs Coulee these are where the climbers climb these are all the the guys tenting there next one beautiful dry waterfalls here cataracts weird all that rock go downstream plucked out by the floodwaters why it's pre-cut and ready to haul Eastern Washington potholes here coking going on all sorts of drama geology go ahead a little dark let's move on crab Creek saddle mountains even some flooding in crab Creek and here's a little stubborn piece of a lava flow that didn't want to get taken away this is not an erratic this is in place but there was a lava flow crossing this whole area most of the lava flow is taken out that guy didn't want to go for whatever reason next one the big giant current ripples at West bar next one a boat for scale hundred yards between crests of these ripples forty feet high each of them will Lou gap where the water is trying to get to the ocean can't buy the tri-cities so it's this constriction that's responsible for some of those secondary temporary lakes next one I know I said five minutes right give me more would you so here's an interesting diagram created by Bruce Bjorn stead of the tri-cities area can you see here's the freeway this is actual photograph Kennewick Richland but taking all the erratic soar the rocks that have been left by these floods that are scattered on these hillsides we've been able to reconstruct that the tippy tops of badger Mountain and candy mountain were not completely flooded but at the maximum of Lake Lewis everything else was under a serious amount of water so that's not an idea this is carefully reconstructed maximum height 1250 elevation above sea level doubt the tri-cities next one some painting done the same thing this is what Vantage would have looked like with glacial Lake Lewis time and the concept for these big rocks being dropped is that they were rafted in here by ice icebergs next one so you find these rocks get sitting out where they shouldn't be big enough that they were probably not just brought in by the floodwater they needed a little bit of help with the raft of ice next one more keep going yeah keep going sure I went to graduate school here in the late 80s and I was focused on the Snake River plain in the lavas but an equally impressive story that I didn't care about that much at the time but I now do is the Lake Bonneville flood story and if you do go to Pocatello down the road there's a great eating spot go ahead Bryce buddies it's a family-owned been there forever and ever it's a tradition to just show up when you visit so remember that buddies in Pocatello Italian food outstanding next one here's a just a quick map glacial Lake Bonneville eventually too much water flood into the snake and get that water all the way to the ocean next one please same idea glacial Lake Bonneville flooded over Red Rock pass and then down the Snake River next one so this is the snake and if you go to the snake anyplace in southern Idaho or in Hell's Canyon you can certainly look at the river and the lavas but there's also scattered flood boulders everywhere from Bonneville next one fifteen thousand years ago next one about that those are all boulders dropped by the flood waters Bonneville flood waters 15,000 next one next one please we don't really have these in our area these heavily polished erratic s' different story they're different volume these are all flood gravels here from Bonneville next one in Hell's Canyon itself this is the last slide coming up next Bonneville flood deposits Missoula floods on top most people ignore the deposits and look at these dramatic coolies and things like that but this is a big part of the story and if you really want to understand the flood history it's the deposits that are going to yield more information to us down the road then the scars themselves this is in Hells Canyon that's about it Pittsburg Landing in Hell's Canyon thank you for coming out tonight appreciate it you

Channel: Central Washington University

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Keywords: Central Washington University Organization, Ellensburg Citytownvillage, flood, Earthquake, geology, nick zentner, volcanoes, History, Zentner Geology Lectures Downtown Ellensburg, Central Washington University, Cwu Geology, Water, pacific northwest, Geology Field Of Study, lava, River, Ice Age Floods, landscape, Central Washingtion University, Cwu Geological Sciences, Education, Cwu, science

Id: ZgVmW_OAB0s

Length: 70min 17sec (4217 seconds)

Published: Tue May 07 2013