SLE102 Lecture Notes - Lecture 2: Laurasia, Subduction, Continental Crust

• School: Deakin University
• Department: Science, Engineering and Built Environment
• Course: SLE102
• Professor: Nick Porch

Document Summary

Mountain building, earthquakes and volcanoes generally occur here. Plate boundaries: geologically unstable regions of the earth. Interior of continents = most geologically stable regions. Mantle around the core (less dense than core but denser than crust) Outer layer; thinnest; liquid: mechanical layers: Asthenosphere ro(cid:272)ks ha(cid:448)e little stre(cid:374)gth; (cid:862)plasti(cid:272)(cid:863); solid (cid:373)aterial that flo(cid:449)s. Hard outer region; rocks cooler and stronger. Lithospheric plates: plates: rigid segments sliding across the top of a mechanically weak part of the. Earth"s (cid:373)a(cid:374)tle: earth"s surfa(cid:272)e has 7 major plates, a(cid:374)d (cid:373)a(cid:374)y (cid:373)i(cid:374)or o(cid:374)es, plates can be made of oceanic or continental crust (or both), plates move between 1-30cm/year. Plate boundaries: divergent plate boundaries pull apart. Plates pull apart a fra(cid:272)ture i(cid:374) the earth"s (cid:272)rust for(cid:373)s magma flows upwards from the earth interior (asthenosphere) magma cools and solidifies forms new rock. 2 types: oceanic ridges and continental rift zones: convergent plate boundaries - collide.