4_isostasy_geodynamo-1

4_isostasy_geodynamo-1 - Isostasy (wrap-up), and earths...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Isostasy (wrap-up), and earths geodynamo GS222 Lecture 4 Overview - this lecture Review of the isostasy homework what did we learn? Why is the earths geodynamo important (to the climate system, plate tectonics, and organisms)? How did the moon form and why should we care? Hypsographic curve Contrast in height largely driven by crustal thickness ~50% of earths surface is deeper than 4000 m Change in sea level of 10 m swamps huge area (millions of km 2) Isostatic rebound Ice sheets were up to 3000 m thick over N. America... Last Ice Age (~20,000 yr BP; 20 kyr BP) Deglaciation (20 kyr to 8 kyr BP) Key points (Isostasy) Earths structure is composed of dense Fe-rich core, and progressively less dense layers including mantle and crust Density dictated primarily by chemical composition (oxygen and silicon key) Rigid lithospheric plates float on asthenosphere (a ductile solid) Floating crustal blocks will reach level dictated by their thickness and density relative to asthenosphere, known as isostatic equilbrium The geodynamo system Magnetic field produced in the fluid outer core of the earth Analogous to bar magnet, inclined ~10 from rotation axis...
View Full Document

This note was uploaded on 01/20/2012 for the course GEO 222 taught by Professor Davidlund during the Winter '11 term at University of Michigan.

Page1 / 15

4_isostasy_geodynamo-1 - Isostasy (wrap-up), and earths...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online