GEOL 1121 Lecture Notes - Lecture 4: Plate Tectonics, Volcanic Arc, Jigsaw Puzzle
17 Mar 2018
School
Department
Course
Professor
Document Summary
Mountain belts include sedimentary rocks were folded and uplifted. So some process is causing the folding. And faulted or broken layers also occur in mountain belts. Linear mountain chains, arcuate deep sea trenches, mid-ocean ridges. In mountain belts, originally horizontal layers are folder and faulted. Deep sea trenches and volcanic island arcs. Continents fit together like a jigsaw puzzle (e. g. south america-africa) Fit is best if the continental shelf is included in the continents; the continent ends at the continental rise. Shallow to deep earthquakes form belts parallel to deep sea trenches and volcanic island arcs; deepest earthquakes are furthest from trench. Shallow earthquakes occur along mid-ocean ridges or in zones away from ocean ridges. Volcanoes commonly form island chains adjacent to deep sea trenches; submarine volcanic activity is also concentrated along mid-ocean ridge system. Most volcanoes (filled triangles) are concentrated in narrow belts. Hawaiian age progression consistent with plate movement of about 9 cm per year.
