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Chapter 10 The Movement of the Earth’s Crust. The forces within the Earth push and pull on the Earth’s Crust. Think back to Section 9.3 The Earth’s Crust. The Earth’s crust moves as a result of the stress or forces within the Earth. Which brings us to Chapter 10
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Chapter 10 The Movement of the Earth’s Crust
The forces within the Earth push and pull on the Earth’s Crust.
Think back to Section 9.3 The Earth’s Crust
The Earth’s crust moves as a result of the stress or forces within the Earth.
Which brings us to Chapter 10 The Movement of the Earth’s Crust
Stress are forces that push and pull on the Earth’s crust causing it to undergo deformation.
Stress Causes rocks to slowly change shape and volume.
Compression Tension Shearing
A Normal Fault occurs when tension or pulling apart acts on a fault. The hanging wall will move down relative to the foot wall.
A Reverse Fault occurs when compression or pulling apart acts on a fault causing the hanging wall to move up relative to the foot wall.
Thrust Fault is a special type of reverse fault that is formed when compression causes the hanging wall to slide over the foot wall.
A lateral fault occurs when shearing acts on a fault which causes blocks of rock to slide horizontally past each other left or right.
Fault-block mountains are formed by blocks of rock uplifted by 2 normal faults. Example: Cordilleran Mountains in Western USA
Rift Valleys are formed by 2 normal faults sliding down Example: Death Valley, California USA
Nearly five and a half million years ago, what we today call Baja California used to be part of the Mexican mainland, and then it began pulling away as tectonic forces underneath split the land apart. Now, Baja California is slowly moving northwest. Some geology experts say that the northernmost extension of this rift, or tear, is the area we call Death Valley, while others claim it to be in the Salton Sea. There is even some plausible scientific evidence to support the idea that this tearing of the land could extend as far north as southern Oregon. There are those who refer to this phenomenon as the Baja Rift.
