GEOL 1304 Lecture 20: Chaptereleven
Document Summary
More dense- 8-10 kilometer thick-younger than continental crust- records magnetic pole position -called. Sima (silicon dioxide + magnesium) - basalt (granular and high in silica and magnesium) Sea-floor public exposure when two diverging lithospheric tectonic plates on the sea oor seperate . As the two plates move apart from each other, (cm per yr ) lava hardens to create new incrustation . Mid-atlantic ridge, east paci c ocean rise(nazca home ). divergent limit are likely to occur at mid ocean ridge yet a few occur on the continents great rift valley (impertinence is rifting apart) A personal line of credit of volcanoes, is known as an island arc. The outermost compositional layer of the solidness globe part of the lithosphere-thinnest layer continental crust(sial ) Thickest (about 30km) -granite (crystalline and high in silica and aluminum) -sial (silica + Exogenic --erosion/weathering vesture the earth down magma molten rock beneath the surface.
