This tells scientists that these rocks on mountaintops were once below the surface of an ocean.
Between 15 and 20 million years ago, when these animals perished, their corpses fell to the ocean floor and became enmeshed in the sediments of the deep. But ever since, the Andean chain's violent upthrusting has thrust the sediments to the summits of mountains.
The fossils are thought to have been transported from the water to the hills by tectonic plate movements or earthquakes. These occurrences are not unfamiliar in California, where the complicated fault lines "guarantee the earth is perpetually shifting [so] ancient rock is always being driven to the surface."
Learn more about marine fossils here:
brainly.com/question/2564225
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