Flashcards in Chapter 16 Deck (54):
study of the earth's dynamic history. Geologists study and analyze rocks and the features and processes of the earth's interior and surface.
Inner zone of the earth. It consists of a solid inner core and liquid outer core.
zone of the earth's interior between its core and its crust.
solid outer zone of the earth. It consists of oceanic crus and continental crust.
move large volumes of rock and heat in loops within the mantle like a giant conveyer belt.
mantle rock flows slowly upward in a column, like smoke from a chimney on cold, calm morning.
various-sized areas of the earth's lithosphere that move slowly around with the mantle's flowing asthenosphere. Most earthquakes and volcanoes occur around the boundaries of these plates.
outer shell of the earth, composed of the crust and the rigid, outermost part of the mantle outside the asthenosphere; material found in earth's plates.
throughout the earth's history, continents have split and joined as plates have very slowly drifted thousands of kilometers back and forth across the planet's surface.
divergent plate boundary
area where earth's lithospheric plates move apart in opposite directions.
convergent plate boundary
area where earth's lithospheric plates are pushed together.
area where the earth's lithospheric plates move in opposite but parallel directions along a fracture (fault) in the lithosphere.
process or group of processes by which loose or consolidated earth materials and dissolved, loosened, or worn away and removed from one place and deposited in another.
physical and chemical processes in which solid rock exposed at earth's surface is changed to separate solid particles and dissolved material, which can then be moved to another place as sediment.
a large rock mass is broken into smaller fragments.
water collects in pores and cracks of rock, expands upon freezing, and splits off pieces of the rock.
one or more chemical reactions decompose a mass of rock.
the conversion of rock or minerals into smaller particles through the action of living.
shaking of the ground resulting from the fracturing and displacement of rock, which produces a fault, or from subsequent movement along the fault.
a measurement used by scientists to determine the magnitude of earthquakes.
gradually decrease in frequency over a period of up to several months.
from seconds to weeks before the main shock.
coastal areas can be severely damaged by earthquakes at sea that can generate huge water waves. aka tidal waves, have nothing to do with tides.
vent or fissure in the earth's surface through which magma, liquid lava, and gases are released into the environment.
a central vent or long crack in the earth's surface.
debris ranging from large chunks of lava rock to ash that may be glowing hot.
any naturally occurring inorganic substance found in the earth's crust as a crystalline solid.
any material that makes up a large, natural, continuous part of the earth's crust.
rock formed when molten rock material (magma) wells up from the earth's interior, cools, and solidifies into rock masses.
rock that forms from the accumulated products of erosion and in some cases from the compacted shells, skeletons, and other remains of dead organisms.
rock produced when a preexisting rock is subjected to high temperatures (which may cause it to melt partially), high pressures, chemically active fluids, or a combination of these agents.
largest and slowest of the earth's cycles, consisting of geologic, physical, and chemical processes that form and modify rocks and soil in the earth's crust over millions of years.
nonrenewable mineral resource
a concentration of naturally occurring nonrenewable material in or on the earth's crust that can be extracted and processed into useful materials at an affordable cost.
part of a metal-yielding material that can be economically and legally extracted at a given time. An ore typically contains two parts: the ore mineral, which contains the desired metal, and waste mineral material (gangue).
deposits of a particular mineral-bearing material of which the location, quantity, and quality are known or have been estimated from direct geological evidence and measurements.
resources that have been identified and fro which a usable mineral can be extracted profitably at present prices with current mining technology.
potential supplies of a particular mineral resource, believed to exist because of geologic knowledge and theory, although specific locations, quality, and amounts are unknown.
removing soil, subsoil, and other strata and then extracting a mineral deposit found fairly close to the earth's surface.
extraction of a metal ore or fuel resource such as coal from a deep underground deposit.
layer of soil and rock overlaying a mineral deposit. Surface mining removes this layer.
unwanted rock and other waste materials produced when a material is removed from the earth's surface or subsurface by mining, dredging, quarrying, and excavation.
removing minerals such as gravel, sand, and metal ores by digging them out of the earth's surface and leaving an open pit.
type of surface mining in which chain buckets and draglines scrape up sand, gravel, and other surface deposits covered with water. It is also used to remove sediment from streams and harbors to maintain shipping channels.
area strip mining
type of surface mining used where the terrain is flat. An earthmover strips away the overburden, and a power shovel digs a cut to remove the mineral deposit. After removal of the mineral, the trench is filled with overburden and a new cut is made parallel to the previous one. This process is repeated over the entire site.
contour strip mining
form of surface mining used on hilly or mountainous terrain. A power shovel cuts a series of terraces into the side of a hill. An earthmover removes the overburden, and a power shovel extracts the coal, with the overburden from each new terrace dumped onto the one below.
type of surface mining that uses explosives, massive shovels, and even larger machinery called draglines to remove the top of a mountain to expose seams of coal underneath a mountain.
Surface Mining Control and Reclamation Act of 1977
requires mining companies to restore most surface-mined land so it can be used for the same purpose as before it was mined.
slow or rapid sinking of part of the earth's crust that is not slope-related.
acid mine drainage
when rainwater seeping through a mine or mine wastes carries sulfuric acid to nearby streams and groundwater.
one of the two components of ore, and it is the waste material.
removing the gangue from the ores produces piles of waste.
process in which a desired metal is separated from the other elements in an ore mineral.
the time it takes to use a certain fraction, usually 80% of the known or estimated supply of a nonrenewable resource at an assumed rate of use. Finding and extracting the remaining 20% usually costs more than it is worth.