Transcription: The Earth's surface layer or crust comprises several rigid plates which float on a bed of soft molten silicate. The molten nature of this bed allows the plates to move in relation to each other, a process known as plate tectonics. Tens of millions of years ago, long before Homo sapiens roamed the planet, the Himalayan mountains were born. Over the course of many millennia this ancient landmass buckled up with reaching high into the skies. Some plates move horizontally alongside one another. As these transform plates slide past each other they cause minor tremors or earthquakes. The San Andreas ...
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