Exam 1 terms Flashcards
lithosphere
solid (rigid)
crust + upper mantle
aesthonosphere
solid (but deformable)
1-2% molten
mantle
peridotite composition (~40% SiO4)
~2800km thick
density 3.3-6 g/cm^3
~80% of Earth’s mass and volume
continental crust
granitic
density ~2.7g/cm^3
20-70 km thick
continental drift
the continents where together at one point and they have drifted apart from one another over billions of years
continental rift
a divergent boundary initiated on a continent
if successful, produces ocean basin
continental volcanic arc
at a convergent boundary between a continental and oceanic plate
the oceanic goes under and melts in the mantle that produces magma and then produces a volcanic chain and produces earthquakes
convergent boundary
plates are moving towards each other
divergent boundary
plates are moving away from each other
hot spot
a stationary mantle plume that has burned a hole in the crust and produces volcanism as the plate drifts over it
does not move
Ex) Yellowstone Stone
island arc
at a convergent boundary where an oceanic plate subducts under another one and the melting of the plates produces volcanoes that eventually form an island
marine magnetic anomalies
mid-ocean ridge
from a divergent boundary with 2 ocean plates where magma is coming up and forming new oceanic plate
oceanic crust
basaltic
density ~2.9 g/cm^3
4-7 km thick
normal and reversed polarity
paleomagnetism
plate tectonics
ridge-push force
rifting
slab-pull force
sea floor spreading
subduction
transform boundary/faults
trench
volcanic arc
mineral
naturally occurring, inorganic, solid, crystalline structure, and chemically homogeneous
streak
the color given off by a mineral when scratched on a plate
hardness
luster
cleavage
alluvial fan
intermediate
assimilation
mafic