EARTH 10 Lecture Notes - Lecture 13: Ice Rafting, Milankovitch Cycles, Sea Level
Document Summary
Erratic boulders - isolated, exotic boulders left behind by glaciers. Glacial flour: fine silt-sized quartz in water that makes lakes/oceans turquoise. Ice rafted debris: icebergs transport materials into the ocean that drops to the seafloor after the iceberg melts. Milankovitch cyclicity = 23k, 41k, and 100k year cycles. Glacial eustasy : worldwide changes in sea level as a result of changing volume of glacier ice on land. Last time earth was in a similar climate regime: 120k years ago (sangamon, mis5e) Marine isotope stage 5e = analogue for current day climate ; sea levels 6-9m higher than today.