Components Of The Lithosphere

Components of the Lithosphere
-Rigid Outer Layer
-Crust and upper mantle
-tectonic plates
Theory of Plate Tectonics
-Theory that Earth's surface is composed of large, thick plates that move and change in size

-Combined hypotheses of continental drift and seafloor spreading, plus new observations using geophysics superconinents Pangea: super continent

-Godwana: (Permian), southern super continent, south America, Australia, new guinea

Lavrasia: northern super continent
Types of Plate Boundaries
Divergent(constructive)

Convergent(destructive)

Transform(conservative)
Preservation:
-Permineralization: petrified wood
-Minerals and cast: impression in material filled in by another
-Carbonization and empression: when carbon film is lost
-Amber: harder resin of ancient trees
Divergent Boundary
-Tension creates rifting
-Creates new ocean basins
-Uplift due to hot, rising, less dense magma
-Shallow earthquakes
-Grabens= normal faulting
Paleontology
study of fossils
Transform Boundaries
-two plates slide past each other
-Offset along other types of plate boundaries
-Shear motion along faults
-May occur as a single fault, or groups of parallel faults
Convergent Boundaries
-two plates coming together
-One subducts and is damages
-Oceanic plate is older, colder, denser, gets subducted
-Characteristics depend on collision type -Ocean-ocean -Continent-continent -Ocean continent
Ocean Ocean Convergence
-subduction causes a benioff zone
-creates a deep broad trench
-Accretionary Wedging: marine sediments are scraped off
-Partial melting of the asthenosphere(due to flux melting)
Magma forms an island arc
Continent-Continent
-Oceanic crust is first subducted until ocean closes
-Neither plate wants to subduct(least buoyant does)
-Forms Suture zone plate boundary(in middle)
-Crust is greatly thickened, creates a large mountain belt and shallow focus earthquakes
-Continental collision, mountain belts, thrust faults, and