GEOG 203 Lecture Notes - Lecture 11: Lithification, Subduction
Document Summary
Oct 2nd geog 203 introduction, rock types, composition and minerology and physical and chemical weathering. Igneous rocks composed of minerals formed from molten magma. Pressure is high and molten lava rises into the crust and cools. Intrusive igneous eruption of lava cools on surface. Rock forms out of these minerals the least shared amount of oxygen will weather much quicker: quartz has a 3d structure which leads to the clear surfaced and large minerals, weathers the slowest. Si tetrahedra shared by si-o-si or fe/mg: depends on the mineral and how much oxygen is shared by silicon atoms. Loss of positive charge leads to loss/ additional buffering. Depends on the size of the ions. K has large size but low charge. Al has small size but large charge. Differences leads to change in bonding strengths. K large so bonding strength wont be that large. Substitution lead to special minerals (feldspars)
