GEO 1111 Lecture Notes - Lecture 12: Layered Intrusion, Plate Tectonics, Potash

• School: University of Ottawa
• Department: Geology
• Course: GEO 1111
• Professor: Robert Jack Cornett

Document Summary

Each person uses 20000kg/yr of crushed rock, cement, gravel . Lots of mining and extraction is for stuff like roads and cement. Ex: stone, gravel, sand, gold, copper, potash, lime, nickel. Evidence of mining more than 160,000 years ago. Metals first used over 20,000 years ago: copper and gold were the earliest used (important elements used for various things see table) Most useful metals in crust are scarce. Most occur as atomic substitutions in more abundant rock-forming minerals. Al : found in bauxite (al is residual product of weathering of bauxite) Fe : banded sedimentary formations; magmatic segregation. A few are oxides (ore minerals of iron, tin and tungsten) They rarely occur alone, they are mixed with gangue (less important stuff) ** source (rocks or magma) > transport (melt or fluid) > trap (physical or chemical) Ex 1: layered mafic intrusion > fractional crystallization > sulphide melting. Ex 2: volcanic eruption > geothermal fluid > hypothermal precipitation.