Only about 5,000 feet of sediment accumulated during middle Mesozoic times (about 200 to 150 million years ago) in the region now occupied by the Southern Rockies. Mountain building in these ranges resulted from compressional folding and high-angle faulting during the Laramide Orogeny, as the Me...
P-waves are able to travel through solids and liquids, which allows them to travel through the Earth's outer core, though they are refracted, or bent. P-waves are compressional meaning that the rocks compress together and expand as the waves pass through them. Think of a slinky being ...
The long linear folds that are characteristic of mountainous regions are believed to have resulted fromcompressional forcesacting parallel to the surface of Earth and at right angles to the fold (see alsomountain). Some geologists believe that many folds are the result ofstratasliding from a vertic...