Oxygen, silicon, aluminum, calcium, iron, magnesium, sodium, and potassium.
What are the major elements of Earth’s crust?
Relation between elements and minerals
elements make up minerals
Isotope
an atom that has the same number of protons but a different number of neutrons.
compound
consists of two or more elements that are chemically combined in specific proportions
covalent bonds
form when atoms share electrons
metallic bonds
form when metal ions share electrons
ionic bonding
forms between negative and positive ions
Characteristics of a mineral
crystalline structure, chemical compound, solid, naturally occurring, and inorganic
silicon-oxygen tetrahedron
the building blocks of all silicates
What is a mineral’s streak?
the color of the powder of a mineral
Which mineral property is least useful?
color
Why would a mineral cleave?
In the atomic structure of a mineral, some bonds are weaker than others. These weak bonds are places where a mineral will break when it’s stressed.
density formula
d=m/v
How are rocks classified?
By how they form
Rock Cycle
slow cooling
underground causes large grains
fast cooling
above ground causes smaller grains
What are the various changes that occur during metamorphism?
new minerals grow with different sizes, shapes, and orientations than those of other minerals.
Contact metamorphism
intruding magma causes localized areas of elevated temperature that alter rock
regional metamorphism
occurs over large areas of Earth’s crust, usually during mountain building, and is associated with very high temperatures and pressure
placer deposits
minerals that fall into the cracks of creek beds
Advantages of solar energy
free, clean, renewable source
Nuclear fusion
a uranium atom is split in a controlled reaction, which creates energy, which generates heat, which boils water, which creates steam that spins a turbine
How does hydroelectric power create energy?
water spins a turbine
point source pollution
pollution from a known and specific location, such as factory pipes
non-point source pollution
pollution that doesn’t have a specific point or origin
When were the most anti-pollution laws passed?
1970s
What is the most important law for air pollution?
Clean Air Act
mechanical weathering
occurs when physical forces break rock into smaller and smaller pieces without changing the rock’s mineral composition
frost wedging
the mechanical breakup of rock caused by the expansion of freezing water in cracks and crevices
What type of weathering is most effective in mid-latitudes?
frost wedging
What affects the rate of weathering?
rock characteristics and climate
In which climate is weathering the most effective?
hot, wet climate
what are the various components of soil
mineral matter, or broken-down rock; humus, which is the decayed remains of organisms; water; and air.
What determines a soil’s texture?
grain size, sand (large), silt, and clay (small)
What is the main source of organic matter in soil?
plants
A horizon
loose and partly decayed mineral matter)
B horizon
clay transported from above
C horizon
partially weathered parent material
pedalfer
usually form in temperate areas that receive more than 63 cm of rain every year. This soil is present in much of the forested areas in the eastern area of the states. The B horizon in this type of soil usually contains a large amount of iron oxide, making it a red-orange color.
pedocal
found in the western US in areas that have grasses and bush vegetation. Since chemical weathering is slower in drier climates, they usually contain less clay than pedalfers. They contain calcite, or calcium carbonate, and are typically a light-gray brown.
laterite
form in hot, wet, tropical areas. Chemical weathering is intense. The large quantity of water that passes through these soils removes most of the calcite and silica. Iron oxide and aluminum are left behind and the iron oxide gives it it’s distinct red color.
soil erosion rates today vs the past
The soil erosion rates are faster today because of human and biological removal of plant life and vegetation
How do humans impact soil erosion?
Human activities that remove natural vegetation, such as farming, logging, and construction, have greatly accelerated erosion
What are the various trigger of mass movements?
saturation of surface materials with water, over steepening of slopes, removal of vegetation, and earthquakes.
over-steepened slope
a steepened slope that exceeds over 40 degrees
What is the general seed of the various mass movements?
creep is the slowest, mudslide is the fastest
fault
a fracture in the earth where movement has occurred
focus
the point where an earthquake starts
foreshock
a small earthquake that can happen days or years before an earthquake
aftershocks
after an earthquake and can happen for weeks or months after the initial quake
P waves
the fastest, can travel through solids, liquids, and gasses
S waves
come second, and can only travel through solids
surface waves
come last and are the most destructive
What are the various scales used to measure earthquakes?
richter scale, seismograph, modified mercalli scale, and momentum magnitude
seismograph
instrument that records earthquake waves
seismogram
comes from the seismograph
How does the Richter scale measure earthquakes?
based on the height of the largest seismic wave based on a seismograph
tsunami
triggered by an earthquake, occurs where a slab of the ocean floor is displaced vertically along a fault
Layers of the Earth defined by physical properties
Lithosphere, Asthenosphere, Lower Mantle, Inner core, Outer Core
Layer of the Earth defined by Composition
Crust, Mantle, Core
Core
below mantle and composed of iron-nickel alloy
mantle
has the igneous peridodite
crust
thin, rocky layer that is mostly made out of granite
lithosphere
crust and uppermost mantle
asthenosphere
below the lithosphere and has the upper mantle
lower mantle
consists of rocks that are very hot and capable of gradual flow
outer core
liquid layer surrounding the inner core
inner core
behaves like a solid due to extreme pressures