OCS 3103: Plate Tectonics

Plate

a rigid unit of the lithosphere that moves as a unit
Plate = lithosphere = crut+upper rigid mantle

Continental Drift (proposed by Alfred Wagner)

continental had moved across the surface of the Earth

Evidence to the Continental Drift

coastline

fossil (similar plant fossils)

geology(rock formations)

paleomagnetism

Earth’s Magnetic Field - Geodynamo

heat driven circulation of liquid iron in Earth’s fluid core constitutes

Seismic Waves

Primary Waves (P-waves)
Secondary Waves (S-waves)
Surface Waves

Primary Waves

compressional waves that are longitudinal in nature

Secondary Waves

shear waves that are transverse in nature, flow though solids

Surface Waves

when body waves reach the surface

Crust Thickness

describes the outermost shell of terrestrial planet,

Isostasy

geological cycle and landforms by describing the balance between the Earth;s crust and upper mantle

Types of Plate Boundaries

Divergent (new crust is generated as the plates pull away from each other)
Convergent (ocean-continent, continent- continent, ocean to continental)
Transform (two plates sliding hortizontally past one another)

Continent - Continent Divergent

Rift Valley in Africa

Oceanic-Oceanic Divergent

Mid-Atlantic Ridge

Oceanic- Continent Convergent

Mt. Rainer
Trenches, Mountains, Volcanoes

Continent- Continent Ocnvergent

Himalayan Mountains

Ocean - Ocean Convergent

Aleutian Island in Alaska 

Tranform

San Andreas Fault

Subduction

occurs when an oceanic plate runs into a continential plate and slide beneath it

Obduction

the sideways and upwards movement of the edge of a crustal plate over the margins of an adjacent plate

Hot Spots and Volcanic Island Chains

mantle plum: sustain long-lastic volcanic activity, often far from the edge od a tectonic plate,

Wilson

describes the opening and closing of ocean basin sand the subduction and divergence of tectonic plates during the assembly and disassembly of supercontinents

Amasia

next supercontinent

Hydrothermal Vents

moves compounds in seawater (mg and SO4)

White Smokers

emit lither-hued that contains barium, calcium, and silicon, lower temp. 

Black Smoker

found in abyssal zones, typically emitting sulfur-bearing minerals or sulfides

Chemosynthesis

vent fauna depeneds on hydrogen sulfide (H2S) oxiding bacteria to form organic matter