SCIENCE 8 Q2 Module 1. EARTHQUAKES AND FAULT | Types of Fault and Types of Stresses

hello my dear students welcome back to our youtube channel this is me again teacher teammate happy new years of course science [Music] [Music] don't forget to subscribe like and hit the notification bell for more updates in science for today's lesson vlog parasating week one now i think module one science aid we're going to discuss about earthquakes and fault okay that is our first topic for this quaker and of course at the end of this activity at the end of this lesson okay we will be using uh models and illustrations to explain the how movements along folds generate earthquakes [Music] of course we have the fall we also have the earthquake and last we're going to discuss about the different types of stresses in the earth's crust okay but before we proceed with our discussion about earthquakes and fall and the different types of stresses in the earth's crust let us watch take time to read and watch the article about the earthquake that happens in luzon which is 5.3 magnitude quake that hits luzon 5.3 magnitude quake hits luzon philippines an earthquake with a magnitude of 5.3 jolted luzon of the philippines on sunday morning the u.s geological survey said the epicenter with a depth of 86.686 kilometer was initially determined to be at 14.04 76 degrees north latitude and 120.525 degrees east longitude the three widely felt earthquake shook the philippines today but it's unclear if they triggered each other the earthquake which struck at 3 18 am local time on sunday was centered in the sea about 31 kilometer 20 miles northeast of lubang island or 89 kilometers 55 miles west of calamba and 65 kilometer 41 miles southwest of balanga the philippine institute of volcanology and seismology or the fee box said the quick measured 5.5 and struck at a depth of 85 kilometer or 53 miles which is relatively deep there is no threat of a tsunami but after sharks are likely according to fee box shaking from the earthquake was felt across the region including in manila and qason city where some said the tremors were strong enough to wake them there were no immediate reports of damage and casualties the philippines is on the so-called pacific ring of fire an arc of fault lines circling the pacific basin which are prone to frequent and large earthquakes volcanic eruptions also occur frequently in the region it is set by the philippine daily inquirer asian news network on may 16 2020 this past few weeks and past few days we heard a lot of news about the different earthquakes that happened in the philippines philippines [Music] okay when we say earth week this is uh this is caused by a sudden sleep on a fall [Music] [Music] one is the tectonic earthquake and the other one is the volcanic earthquake so when we say tectonic earthquake this is caused by the movement of the frost plates aparra earthquake is a sudden an earthquake is caused by a sudden sleep on a fall the tectonic plates are always slowly moving but they get stuck at their edges due to friction when the stress on the edge overcomes the friction there is an earthquake that releases in the form of energy in waves that travel through the earth's interior and crust that cause the shaking that we feel friction between the two sides of a fault keeps it from moving until the stress on the fold overcomes the friction then the fault slips and creates an earthquake what is fall fold is a fracture or zone of fractures between two blocks of rock folds allow the blocks to move relative to each other this movement may occur rapidly in the form of an earthquake or may occur slowly in the form of the crib few millimeters is this is only a device that can detect the magnitude of the earthquake [Music] remember that energy from the earth's interior makes the ground move friction hold the rocks together but once the friction is overcome the kaharana movement from the ground and then suddenly the earthquake will occur and always remember that earthquake of course when there is a sudden sleep [Music] [Music] [Music] foreign [Music] [Music] [Music] earthquakes are caused when fall sleep suddenly [Music] are classified according to the movement of two blocks now let us identify the different types of false so we have three types of faults number one we have the normal fold we also have the reverse fold and number three is the stripe slip fold it's a normal fold axabilito it occurs when the hanging wall moves down relative to the foot wall so begin example so you adding two blocks of rocks okay so it occurs when the hanging wall hanging wall moves down relative to the foot wall so [Music] [Music] a deep sleep fold in which the block above the fold has moved downward relative to the block below this type of faulting occurs in response to extension occurs when the hanging wall moves down relative to the foot wall okay number two is what we call the reverse fault so pakistan okay so for example we have the foot wall and we have the having wall so it occurs when the hanging wall moves up or thrust over the foot wall so since the boom go on reverse fault a deep sleep fold in which the upper block above the fold plane moves up and over the lower block this type of folding is common in areas of compression when the deep angle is shallow a reverse fault is often described as a chest fault a course where the hanging wall moves up or is stressed over the foot wall and number three or the third type of fault is what we call the strike slip phone so attendance in the manito is the kahrun slides block of rocks so for example adding two blocks of rock sodium uh for example into you adding two blocks of rock so in the is like the mancha and opal so okay and the best example of strike slip fault is what we call the san andreas fault strike slip fold a fold on which the two blocks slide past one another okay there are two types of strike slip fault number one is the the left lateral strike slip fold and the other one is the right lateral strike lateral strike sleep fold but if it is right lateral stretch default you write so that is the difference between the left lateral strength sleep fold and the right lateral strike sleep fold and those are the different types of phone again the normal fold the reverse fold and the strike slip fold or the right lateral and the left lateral strike slip fold a left lateral strike slip fold if you were to stand on the fold and look along its length this is a type of strike slip fold where the left block moves toward you and the right block moves away a right lateral strike slip fold is when you were to stand on the fold and look along its length this is a type abstract slip fold where the right block moves toward you and the left block moves away now let us discuss about the different types of stresses in the earth's crust and you know that earth has three layers it composes of three layers which are the crust the mantel and the core so you press parasha pointing attention it compares [Music] eggshell i know you balance can also symbolize the earth's crust at pakistan earth's crust is the thinnest layer of the earth and pull in this continental plates stress when the plates are pushed and pulled together stress occurs and we have four different types of stress that affects the earth's crust number one we have the compression stress next we have the tension stress we also have the shear stress and number four we have the confining stress compression stress compression is a type of stress that causes the rocks to push or squeeze against one another it targets the center of the rock and can cause either horizontal or vertical orientation in horizontal compression stress the crust that can thicken or shorten in vertical compression stress the chest can thin out or break off the force of compression can push rocks together or cause the edges of each plate colliding to rise mountains are a result of high impact compression stress caused when two plates collided okay when the rocks uh it causes the rocks to push or squeeze when with each other so causes the rocks to push or squeeze against one another for example for example okay now let us talk about the tension stress okay the tension stress this is opposite number one compression stress kusa compression and pushing and squeezing of one lip with another you didn't stress uh tension which is a super continent that existed during the paleozoic and mesozoic era so but because of the stress thus tension stress the tendency of the tension forces of a urak's eye they pull apart and they separate from one another tension stress tension is the opposite of compression while compression forces the rocks and crusts to collide and move together tension forces the rocks to pull apart tension can happen in two ways two separate bleeds can move farther away from each other or the ends of one plate can move in different directions [Music] which is the shear stress okay i'm sure stress it pushes the crust away in different directions [Music] shear stress when shear stress occurs the force of the stress pushes some of the crust in different directions when this happens a large part of the crust can break off which makes the plate size smaller shear stress usually happens when two plates rub against each other as they move in opposite directions the friction of a shear stress at the edges of the plate can cause earthquakes and for the last type of stress we have the confining stress confining stress okay so upon finding stress it only of course kappa young stress and apply [Music] when stress is applied to all sides of the crust confining stress occurs when this happens the grass compacts which makes it look smaller if the stress is too much for the grass to handle the crust can fracture from the inside this causes the crust weight to decrease but the crust shape remains the same because this type of stress can hollow out of the insides of the crust confining stress can cause sinkholes in the earth this is the end of our lesson vlog in science 8 for week 1 so i hope you learned something from me thank you for listening and watching this lesson vlog this is me again featuring me if you are new to my channel don't forget to subscribe like and hit the notification bell for more updates see you on my next vlog you

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Length: 25min 59sec (1559 seconds)

Published: Mon Jan 04 2021