Here's why:
* Compressional stress is a force that pushes rocks together. This squeezing action causes the rocks to shorten in one direction (becoming thinner) but thicken in the other direction.
* Tensional stress pulls rocks apart, making them thinner.
* Shear stress causes rocks to slide past each other horizontally, often resulting in deformation or fracturing.
Examples of how compressional stress thickens rocks:
* Mountain building: The collision of tectonic plates creates immense compressional stress, pushing rocks upwards and thickening the Earth's crust, forming mountains.
* Folding: Compressional stress can cause layers of rock to bend into folds, resulting in thicker areas.
* Faulting: When rocks are compressed beyond their elastic limit, they can fracture, creating faults. The compressional stress can push rock masses against each other, thickening the rock on one side of the fault.
Let me know if you'd like to explore any of these examples in more detail!
