OnTopic: Rocks--The Building Blocks of Mission Trails Regional Park скачать в хорошем качестве

OnTopic: Rocks--The Building Blocks of Mission Trails Regional Park

Geologist Patrick Abbott, professor emeritus at San Diego State University, explorer, guide, and author presents the first of three lectures about the geology of Mission Trails. Presentation overview: Take eight common elements. Arrange them into different structures thus making eight common minerals. Subject these minerals to different temperatures and pressures, and form three major groups of rocks: Igneous, Sedimentary, and Metamorphic. Igneous rocks form when magma cools at the surface as volcanic rocks or below ground as plutonic rocks. Weathering decomposes and disintegrates surface rocks, then the resulting debris is moved and deposited to form sedimentary rocks. Bury rocks deeply and the elevated temperatures and pressures cause transformation into metamorphic rocks. These are the "building blocks" of MTRP. This presentation is made possible through funding from SDG&E and donors to the Mission Trails Regional Park Foundation.