when the planet was formed (big bang)
when were the earth's resources determined?
the innermost zone of the planet, made of nickel and iron
above core, contains magma
the outermost layer
located in the outer part of the mantle, composed of semi-molten, ductile rock
outermost layer, 100 km thick, brittle, made up of crust and solid upper mantle
uppermost portion of mantle
lowest part of lithosphere=
plumes of magma to well up from the mantle
intense heat at the center of the earth causes what?
places where molten material from the mantle reach the lithosphere
the continuous change, creation, and renewal of earth materials in the lithosphere
what does mantle convection drive?
heat in earth's core
what is mantle convection created by?
what is the coolest thing about tectonic plates?
because they are denser (contain more iron)
why do oceanic plates slide under continental plates?
they make magma and cause volcanoes
what happens when plates move over hot spots?
divergent plate boundaries
when plates move apart from one another: sea floor spreading
sea floor spreading
helps us gain access to elements
convergent plate boundaries
when plates move toward one another
narrow mountain range
oceanic+continental plates converge
large mountain range; dramatic collision
continental+continental plates converge
transform fault boundaries
plates move sideways alongside each other
a fracture in rock across which there is movement
occur when the rocks of the lithosphere rupture unexpectedly along a fault
large expanses of rock where movement has occurred
the exact point on the surface of earth directly above the location where the rock ruptures.
a measure of the largest ground movement that occurs during an earthquake. the scale increases by a factor of 10
the constant formation and destruction of rock. it is really slow.
rocks that form directly from magma
form from within earth as magma cools
form when magma cools above earth
occur when rock cools and is subject to stress
form when sedimentary rocks such as mud, sand, or gravel are compressed by overlying sediments. form sand dunes,etc.
when sedimentary rock, igneous rock, other metamorphic rocks are subjected to high temperatures and pressures
when rocks are exposed to air, water, certain chemicals or biological agents that degrade the rock
the physical breakdown of rocks and minerals
breakdown of rocks and minerals by chemical reactions; it makes caves
the physical removal of rock fragments from a landscape or ecosystem. wind, water, ice transport the material, living organisms can erode materials as well
the accumulational depositing of eroded material such as sediment, rock fragments, or soil
weathering breaks things down, erosion moves things from point a to point b
difference between between weathering and erosion
erosion, deposition, and weathering
these 3 processes make soil
why soil is important
a medium for plant growth, serves as a filter for water, habitat for living organisms, serves as a filter for pollutants
factors that determine formation of soil
parent material, climate, topography, organisms, time
rock material underlying soil from which inorganic components are derived
horizon that contains organic matter in various stages of composition
horizon that contains underlying organic material mixed with underlying mineral material
subsoil; horizon where metal and nutrients accumulate
subsoil; horizon that is least-weathered, similar to parent material
determined by percentage of sand, silt, and clay- use triangle
composition of loam
cation exchange capacity
the ability of a soil to absorb and release cations positively charged mineral ions
calcium, magnesium, potassium, and sodium
aluminum and hydrogen
the proportion of soil bases to soil acids
bacteria, fungi, and protozoans (80-90%); snails, slugs, insects, earthworms, rodents also there
the known quantity of a resource that can be economically recovered
removing minerals that are close to earth's surface
removing strips of soil and rock to expose ore
open pit mining
the creation of a large pit/hole in the ground that is visible from the surface
removing the entire top of a mountain with explosives
looking for metals and stones in river sediments
when desired resource is more than 100 meters below earth's surface
how subsurface mining is accomplished
horizontal tunnel dug into the side of a mountain/other feature containing resource; miners go through vertical shafts on elevators