Wpr2 Flashcards
Oceanic crust. Magmas with low amounts of silica. Dark colored magnesium and iron rich materials.
Mafic
Formed by cooling and solidification of molten rock. “Welding of tiny pieces of solid volcanic rock.
Igneous
Continental crust. Magmas with large amounts of silica. Light colored silicate materials such as quartz and feldspar. Low densities and melting temps.
Felsic
Formed through the accumulation of sediment. Consolidated through compression and cementation. Characteristic= stratification.
Sedimentary
Formed by exposing igneous or sedimentary rock to high pressure and temp. Causes a change in mineral structure, composition and rock texture.
Metamorphic
Magmas cools below surface. Slower cooling process. Coarse grained, large crystals/minerals. Granite(felsic) Gabbro(mafic)
Igneous intrusive
Lava cools above surface, faster cooling. Fine grained, small crystals. Basalt (mafic) obsidian (felsic)
Igneous extrusive
Sediments of other rocks are compacted and cemented, layered. Sandstone and shale.
Sedimentary Detrital
Solids precipitate out of solution. Soluble. Limestone, travertine.
Sedimentary chemical
Sedimentary and igneous rocks exposed to heat and uneven pressure. Minerals align: bands wavy structure. Gneiss, slate.
Metamorphic foliated
Even pressure. Large crystal growth, 1 mineral dominates. Marble, quartz
Metamorphic non-foliated
Wearing down or destructive processes which decreases relief.
Denudation
Mid ocean ridges formed by currents of magma rising up from mantle. This creates new basaltic ocean floor that spreads away laterally from ridge and creates me crust. Older oceanic crust is subducted back into the crust and recycled.
Sea floor spreading
Plutonic, form from the cooling of magma below the surface.
Intrusive
Volcanic, form from the cooling of lava or the bonding of pyroclastic materials on the surface.
Extrusive
Organically accumulated sedimentary rocks. Formed by the remains of dead plant material.
Sedimentary organic
Plates diverge, magma wells up in the opening between plates. Constructive because material is being added to the crust. Represented by mid ocean ridge.
Divergent boundary
Plates collide. Destructive because the result in removal of or compression of the surface crust. Responsible for major mountain ranges,volcanoes and oceanic trenches.
Convergent boundaries
Tow plates slip past one another laterally. Neither create or destroy crust. Associated with seismic activity, producing shallow focus earthquakes. Most are along mid ocean ridge system
Transform boundary
Occurs at plate boundaries (causer of earthquakes)
Seismicity
Result when magma rises to the earths surface. Occurs when tectonic plates are subducted. Convergent or divergent plate boundaries
Volcanoes
Large, steeply sided volcanoes. Explosive eruptions. Vicious lava. Felsic.
Composite volcano
Gentle, nonexplosive eruptions. Low viscous lava. Mafic
Shield
Steeper than composite volcanoes, intermediate volatile contents. Mafic. Reddish- brown pyroclastic debris.
Cinder