Nvironmental Geology Rock Outcrop Formation/Plate Tectonics
In the section summary reports you are to show your individual mastery of the topics covered. The text must be in your own words (quotes no more than 10% at the most), include all sources and avoid any type of plagiarism. Now to the first paper. Please complete both tasks.
Task 1: You find an outcrop showing the following rocks. The lower most unit is a coarse-grained granite dated at about 250 million years. The upper surface of the granite is irregular and wavy. The second unit starts with a coarse-grained, cross-bedded sandstones which becomes finer-grained upwards. The marine bivalves and crinoids in the upper part of the sandstone place the unit in the Upper Jurassic. The sandstone is then gradually replaced by marl and then pure limestone containing mussels, corals, algae, sea-urchin fragments etc.
Describe the developmental setting of each rock unit and the development of the entire sequence. What do the different ages of the magmatic granite and the sedimentary rocks tell you?
Task 2: The west coast of North America consists geologically of a jumble of geological units of greatly varied age and origin. Explain the plate tectonic struture and processes in the region.