chapter 11 Flashcards
Geology
- the scientific study of dynamic processes
taking place on the earth’s surface and in its interior
earth was found how. many years ago?
4.6 billion years ago
Core
the innermost layer of the earth and is
composed primarily of iron (Fe)The inner core is hot and solid.(egg yolk)
Mantle
the zone of the earth that surrounds the
core and is made of solid rock which can be soft and
pliable at high temperatures.
Asthenosphere
the outermost layer of the mantle
made of hot, partly melted flowing rock.
outercore
is surrounded by
molten, or hot fluid, rock. (egg white)
Asthenosphere
the outermost layer of the mantle
made of hot, partly melted flowing rock.is the soft, jelly-like layer of the mantle under the crust. It’s where rocks are so hot they can flow slowly, like melted plastic.
convection currents
are created as the
innermost material
heats and rises then
cools and sinks back
to the core.(pot)
magma
Molten rock from
the asthenosphere
which flows to the crust and is called(magma underground)
lava
Magma that
erupts to the earth’s
surface is called (above ground)
continental crust
the crust where all the land is
oceanic crust
where the land is underneath the sea(thinner due to the water pushing it down)71% of the earths crust is oceanic
lithosphere
This zone
contains the
mineral
resources that
we use
divergent boundaries
to go in 2 different directions.magma
flows up where the plates separate
forming new land and causing
volcanic eruptions and geysers.(pulling apart a cut)
convergent boundaries
when two plates push into each other.two
tectonic plates collide, one sinks
under the other causing it to melt
and causing the other plate to rise
forming mountains. All the land that melts causes escape pockets that create volcanos
transform boundaries
two
tectonic plates grind against each
other in opposite directions causing
earthquakes, mountains, and deep
cracks.
mineral
- a naturally occurring chemical element or inorganic compound that exists as a solid with a
crystalline structure. They take millions of years to form.(nonrenewable)
Silver
Ag
Rock
a solid combination of one or more minerals found in the earths crust
limestone
CaCO3
what are the three kinds of rocks
sedimentary
igneous
metamorphic
Sedimentary
rocks are made of
sediments - dead plant and animal
remains and particles of eroded rock.
Igneous
rock forms below or on the
earth’s surface under intense heat and
pressure when magma cools and
hardens.
Metamorphic
rock forms when an
existing rock is subjected to high
temperatures, high pressures, and or
chemically active fluids
erosion
when rock or solid structures are worn away
rock cycle
uses
the processes of
erosion, melting,
and metamorphism
to change the earth’s
rocks from one type
to another.
bedrock
the deepest layer of the rock
R
bedrock source of all soil
O
(organic horizon) leaf litter, plants, anything that’s alive or was once alive
A/E
(surface horizon)a lot of water, nutrients, and air
B
(subsoil)more rocks and minerals
C
(substratum) everything but blended its mixed through water and air all layers blended
fertile
able to produce life easy to grow plants
humus
the mix of decomposing organic material and parent material mixed with mineral form weathered rock
where is soil formation faster?
it is faster in climate that are wet and warm
deserts and tundras
have underdeveloped soils
rainforest
is low in nutrient and is acidic
soil made of up what?
clay, slit,sand
clay size
small
slit size
medium
sand size
large
space between particles, the bigger the space
porosity
the bigger the porosity determines the…
soil texture
water perolates
the texture determines how quickly water percolates or runs through it is also called soil permeability
CEC
(cation exchange capacity) low porosity, low permeability, sticky
reserves
Most estimates of the supply of a given
mineral resource (nonrenewable) refer to
its reserves: identified deposits from which
we can extract the mineral profitably at
current prices.
economically depleted
We have never completely run out of a
nonrenewable mineral resource, but a
mineral becomes economically depleted
when it costs more than it is worth to
find, extract, transport, and process the
remaining deposits
Depletion time
is the time it takes to use up 80% of the reserves of a mineral at a given rate of use.
curve A
shortest depletion time
curve b
longer depletion time
curve c
longest depletion time
depletion allowances
Mining companies get a tax break! They can subtract 5-22% of the money they make from selling minerals (gross income) to cover the costs of digging and extracting. This lowers their taxes and helps them save money.
biomining
One way to improve mining technology and reduce its environmental impact is to use a biological approach called biomining. Bacteria is used to remove metals from ores, leaving the surrounding environment undisturbed and reduces the air and water pollution associated with removing the metal
from metal ores.
Hydrothermal vents
on the ocean
floor creates ore deposits called
black smokers rich in copper, lead,
iron, zinc, gold, and some rare
earth metals.
Manganese nodules
on the Pacific
The ocean floor can be sucked up
through vacuum pipes or scooped
up by underwater mining
machines.
Open-pit mining
Machines dig large pits to remove metal ore
Overburden
is the waste material removed
during mining processes including
vegetation, soil, and rock overlaying a
mineral deposit.
spoils
Overburden is deposited
in piles called spoils.
strip mining
Extracts mineral deposits in a large horizontal bed close to the earth’s surface.
Contour Strip Mining
● Mostly for coal
● Hilly or mountainous terrain
● Cut into the wall and remove
overburden and mineral
mountaintop removal
blows up the top of mountain. dirt are dumped into valleys and streams and increases flood risk
The US Surface Mining Control
and Reclamation Act of 1977
requires the restoration of
surface-mined sites. However,
the program is underfunded and
many mines have not been
reclaimed
subsurface mining
-Produces less
waste
● Hazardous
cave-ins,
explosions, and
fires
● Lung disease
● Subsidence
Acid Mine Drainage
- rainwater seeps through an
underground mine or a spoils pile from a surface mine and carries sulfuric acid (H2
SO4) is produced by aerobic bacteria in nearby streams and groundwater.
tailing
Removing metal from ores
creates
smelting
is the process of
using heat or chemicals to
release the metals from the
ore.
