ERS 101 Study Guide - Quiz Guide: Mid-Ocean Ridge, Pelagic Sediment, Continental Shelf

• School: University of Maine
• Department: Earth Sciences
• Course: ERS 101
• Professor: A L I C E K E L L E Y

Document Summary

Surface of the lithosphere is not smooth, there are differences in elevation that creates ocean basins and continents. Oceanic lithosphere rests on the asthenosphere because of isostasy. Continental shelf: a relatively shallow portion of the ocean that fringes the continent (water depth does not exceed 500 m). they overlie passive-margin basins. Continental slope: when the continental shelf start to merge (depth nearly 4 km). Continental rise: slope angle decrease until you find yourself above a vast, nearly horizontal surface called abyssal plain. Submarine canyons: deep valleys which downcut into continental shelves and slopes. Seafloor spreading divergent boundary mid-ocean ridge. Oceanic crust moves away from the axis of the mid ocean ridge two changes 1) lithosphere cools and so the surface sinks 2) accumulation of pelagic sediments that also covers the basalt of the oceanic crust. Overall oceanic crust gets progressively older and sediment thickness increases broad areas of old and flat seafloor are called abyssal plains.