glossary.html

Geology of Energy Resources

Glossary



A

Acid Rain
Anthracite
Anticline
Ash Content

B

Binary Plant
Bio-fuels
Bituminous
Btu

C

Cementation
Clean Coal Technology
Coal
Coal Grade
Coal Rank
Compaction
Continuous Mining
Conventional Mining
Cyclothem

D

Delta

E

Erosion
Eustatic Sea-level Fluctuation

F

Fault
Flash Plant
Fold
Fossil Fuel
Fracture
Fumarole

G

Geologic Time Scale
Geophysical Log
Geopressured Reservoir
Geothermal Energy
Geothermal Gradient
Geyser
Greenhouse Effect
Greenhouse Gasses

H

Heat Flow
High Level Nuclear Waste
Hot-dry Rock
Hot Spring
Hydrocarbon
Hydroelectric Power
Hydrothermal System

I

Isotopes

L

Lignite
Limestone
Lithification

N

Natural Gas
Nuclear Fission

O

Oil Window
Organic Matter

P

Peat
Permeability
Petroleum
Petroleum Maturation
Petroleum Migration
Pinch Out Trap
Plate Tectonics
Porosity

R

Radioactive Decay
Reclamation
Remote Sensing
Renewable Energy Resources
Reserve
Reservoir Rock
Resource
Room and Pillar Mining

S

Sandstone
Sediment
Sedimentary Rock
Seismogram
Seismology
Shale
Solar Energy
Source Rock
Stratigraphic Trap
Structural Trap
Subbituminous
Surface Mining
Syncline

U

Unconformity

W

Weathering

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    Acid Rain

    Precipitation with an anonymously low pH, that forms when sulfur dioxide (SO2) emissions react with water to form sulfuric acid (H2SO4).

    Anthracite

    The highest rank of coal with the highest carbon content (86-98%) and a heat value of approximately 15,000 btus/pound. Related Term: Coal Rank

    Anticline

    An up fold in rocks that resembles an arch. Related Term: Fold

    Ash Content

    The concentration of noncombustible silicate minerals and metals in coal. Ash makes up 5 to 20% of the original coal. It reduces the quality of coal by lowering the heat content and causing disposal problems. Related Term: Coal Grade
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    Binary Plant

    A geothermal power plant that utilizes a heat exchanger and secondary fluid to turn the turbine. Related Term: Geothermal Energy

    Bio-fuels

    An alternative energy source that utilizes plant material and animal waste. Related Term: Renewable Energy Resources

    Bituminous

    A coal of intermediate rank, that is the most plentiful type of coal in the United States. Bituminous coal contains 45-86% carbon and has a heat value of 10,500 to15,500 btus/pound. Related Term: Coal Rank

    Btu

    British Thermal Units are the amount of energy required to raise the temperature of one pound of water one degree Fahrenheit.
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    Cementation

    Lithification of sediment by precipitation of minerals in void spaces. Related Term: Lithification

    Clean Coal Technology

    Technology designed to reduce the emissions produced from burning coal by removing impurities and increasing burning efficiency. It includes coal washing, fluidized bed combustion, scrubbers and coal gasification.

    Coal

    A combustible earth material formed from the remains of plants, which contains at least 70% carbonaceous matter. Related Term: Fossil Fuel

    Coal Grade

    A measure of coal quality which is dependent on the amount of impurities such as sulfur and coal ash. Related Term: Ash Content

    Coal Rank

    Classification of coal ranging from lignite to anthracite which reflects the progressive response of coal deposits to increasing heat and pressure. Carbon content and heating value increases with increasing rank. Related Terms: Anthracite, Bituminous, Subbituminous, Lignite

    Compaction

    Lithification of sediment by grain deformation and rearrangement of grains due to overburden pressure. Related Term: Lithification

    Continuous Mining

    A coal mining technique where coal is cut from the face and loaded directly onto a conveyor belt that carries it to the surface. Related Term: Conventional Mining

    Conventional Mining

    An older coal mining technique which involved blasting the coal, followed by loading it onto shuttle cars which carry it to the surface. Related Term: Continuous Mining

    Cyclothem

    A vertical sequence of cyclically repeated sedimentary deposits, resulting from alternating periods of marine and nonmarine deposition. Cyclothems commonly contain coal deposits.
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    Delta

    An accumulation of sediment, formed where a stream enters a lake or ocean.
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    Erosion

    The removal of the products of weathering through incorporation and transportation of material by water, wind, or ice. Related Term: Weathering

    Eustatic Sea-level Fluctuation

    Global changes in sea-level which are caused by various processes such as the waxing and waning of glaciers. Related Term: Cyclothem
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    Fault

    A break or rupture in a rock mass along which movement has occurred. Related Terms: Fracture, Structural Trap

    Flash Plant

    A geothermal power plant where hydrothermal fluids are converted to steam in order to turn the turbines Related Term: Geothermal Energy

    Fold

    A bent series of rock layers that were originally horizontal and subsequently deformed. Related Terms: Anticline, Syncline, Structural Trap

    Fossil Fuel

    Fuels derived from the remains of once living organisms, predominately plants, which includes coal, natural gas, and petroleum. Related Terms: Coal, Natural Gas, Petroleum

    Fracture

    A break or rupture in a rock mass, that lacks appreciable movement. Related Term: Fault

    Fumarole

    A vent, open at the earth's surface, that emits hydrothermal gasses and steam. Related Term: Hydrothermal System
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    Geologic Time Scale

    A chronological arrangement of geologic events, with the major subdivisions, from oldest to youngest, of Precambrian, Paleozoic, Mesozoic and Cenozoic.

    Geophysical Log

    A record of the petrophysical properties of rocks at a well site, such as density, resistivity, sonic potential and gamma ray activity. It is recorded by dropping a tool down the bore hole and recording the property value versus depth.

    Geopressured Reservoir

    The use of deep sedimentary basins which contain a mixture of hot water and methane as a geothermal energy resource. Related Term: Geothermal Energy

    Geothermal Energy

    The use of earth's internal energy to produce electricity, or for space heating. Related Terms: Binary Plant, Flash Plant, Geopressured Reservoir, Hot-dry Rock

    Geothermal Gradient

    The increase in temperature with depth in the earth's crust. Related Terms: Geothermal Energy, Heat Flow

    Geyser

    A fountain of hot water and steam that ejects periodically, which is associated with hydrothermal systems. Related Term: Hydrothermal System

    Greenhouse Effect

    The process where incoming solar radiation of relatively short wavelength is absorbed by the earth and reradiated as longer wavelength, infrared radiation, which is absorbed by the earth's atmosphere. The net result being an increase in the earth's surface temperature. Related Term: Greenhouse Gasses

    Greenhouse Gasses

    Gasses capable of absorbing infrared radiation leading to the "greenhouse effect," which include water, carbon dioxide, methane, nitrous oxide and ozone. Related Term: Greenhouse Effect
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    Heat Flow

    Dissipation of the earth's internal energy by conduction and radiation at the surface. Related Term: Geothermal Gradient

    High Level Nuclear Waste

    Spent nuclear fuel rods that were used in a nuclear reactor and residual from nuclear weapons production.

    Hot-dry Rock

    A method of developing geothermal energy where two wells are drilled in an area with a high geothermal gradient. The rocks are fractured between the two wells. Cold water is pumped down one well and hot water is pumped up the other well. Related Term: Geothermal Energy

    Hot Spring

    A natural spring who's water has an anomalously high temperature that is associated with a hydrothermal system. Related Term: Hydrothermal System

    Hydrocarbon

    A compound composed of carbon and hydrogen atoms that was derived from organic matter. Related Terms : Natural Gas, Petroleum

    Hydroelectric Power

    Electricity generated by the energy of flowing or falling water. Related Term: Renewable Energy Resources

    Hydrothermal System

    Geothermal system characterized by the presence of hot water. Requirements for the development of hydrothermal systems include, a heat source, permeable rocks, the presence of water and a cap rock. Related Terms : Geothermal Energy, Fumarole, Geyser, Hot Spring
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    Isotopes

    Atoms having the same number of protons (atomic number) but a different number of neutrons (atomic mass).
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    Lignite

    The lowest rank of coal which contains 25-35% carbon and has a heat value of 4,000 to 8,300 btus/pound. Related Term: Coal Rank

    Limestone

    A sedimentary rock composed mainly of calcium carbonate (CaCO3) which is most often secreted by organisms. Related Term: Sedimentary Rock

    Lithification

    The process of converting loose, unconsolidated sediment into a solid rock. Related Terms: Cementation, Compaction
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    Natural Gas

    Naturally occurring gasses found in sedimentary rocks. Related Terms: Fossil Fuel, Hydrocarbon

    Nuclear Fission

    Splitting of unstable nuclei into at least two parts with the ejection of neutrons and emission of energy.
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    Oil Window

    The depth where the most oil is produced, which corresponds to a temperature range of 60 to 120 degrees Centigrade. Related Term: Petroleum Maturation

    Organic Matter

    Material derived from living organisms which consist of a carbon-carbon bonded framework with bonded hydrogen, oxygen, nitrogen, phosphorous, and sulfur.
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    Peat

    A dark brown or black residue produced by alteration of plant material which accumulated in a swamp, bog, or marsh environment. Related Term: Coal

    Permeability

    The ease with which fluids can pass through a rock. Related Term: Porosity

    Petroleum

    Naturally occurring liquid oil in the earth's crust, consisting primarily of hydrocarbons.
    Related Term: Fossil Fuel, Hydrocarbon

    Petroleum Maturation

    Conversion of organic matter to petroleum by an increase in temperature during burial of sediments. Related Term: Oil Window

    Petroleum Migration

    The movement of petroleum from the source rock to the reservoir rock either during, or after maturation. Related Terms : Petroleum Maturation, Source Rock, Reservoir Rock

    Pinch Out Trap

    A type of stratigraphic trap where porous rocks are surrounded by impermeable rocks due to a facies change (change in depositional environment) such as a lens of sandstone surrounded by shale. Related Term: Stratigraphic Trap

    Plate Tectonics

    The theory that the earth's outer shell consist of individual plates. Interactions between plates results in phenomena such as earthquakes, volcanoes and mountain building.

    Porosity

    The amount of void spaces in a rock which determines the amount of fluid (water or petroleum) it can hold. Related Term: Permeability
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    Radioactive Decay

    The spontaneous decay of unstable atomic nuclei.

    Reclamation

    Restoration of a landscape to it's original state, or better, following surface mining. Related Term: Surface Mining

    Remote Sensing

    The acquisition of data by a recording instrument that is not in physical contact with the object of study, including, aerial photography and satellite imagery.

    Renewable Energy Resources

    Energy resources that can be continuously replaced after consumption such as bio-fuels, hydroelectric power, and solar energy. Related Terms: Bio-fuels, Hydroelectric Power, Solar Energy

    Reserve

    Estimated quantities that engineering or geologic analysis demonstrate to be producible under current economic operating conditions. Related Term: Resource

    Reservoir Rock

    A porous and permeable rock that contains oil or natural gas. Related Terms: Permeability, Porosity

    Resource

    Known or hypothetical concentrations that can now or in the future be developed as energy sources. Related term: Reserve

    Room and Pillar Mining

    A system of mining where coal is mined in rooms separated by narrow pillars which support the mine ceiling.
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    Sandstone

    A detrital sedimentary rock composed of sand sized (.06-2 mm) particles. Related Term: Sedimentary Rock

    Sediment

    Unconsolidated particles created by the weathering and erosion of rocks, by chemical precipitation of minerals from water, or by organic secretions. Related Term: Sedimentary Rock

    Sedimentary Rock

    Rock formed by the accumulation and lithification of sediments deposited by water wind or ice. They are characterized by a layered structure known as bedding or stratification. There are two types of sedimentary rocks: 1) Detrital sedimentary rocks are composed of solid particles derived from weathering. 2) Chemical sedimentary rocks are formed when dissolved substances are precipitated either by living organisms or inorganically. Related Terms: Sediment, Lithification, Sandstone, Shale, Limestone

    Seismogram

    The record made by a seismograph which is used to determine the structure of rocks in the subsurface.
    Related Term: Seismology

    Seismology

    The study of sound waves transmitted through the earth. Related Term: Seismogram

    Shale

    A laminated detrital sedimentary rock composed of clay sized (<.004 mm) material. Related Term: Sedimentary Rock

    Solar Energy

    Harnessing energy produced by the sun. Related Term: Renewable Energy Resources

    Source Rock

    Rocks that have the potential of producing oil or natural gas. They must have a high organic matter content and have reached thermal maturation. Related Terms: Organic Matter, Petroleum Maturation

    Stratigraphic Trap

    A petroleum trap consisting of a break in the stratigraphic sequence produced at the time of deposition, such as an unconformity or pinch out. Related Terms: Pinch Out Trap, Unconformity, Structural Trap

    Structural Trap

    A petroleum trap formed by deformation of the strata following deposition, such as a fault or a fold. Related Terms: Fold, Fault, Stratigraphic Trap

    Subbituminous

    Coal of intermediate rank. Subbituminous coal contains 35-45% carbon and has a heat value of 8,300 to 13,000 btus/pound. Related Term: Coal Rank

    Surface Mining

    Mining at the earth's surface by use of earth moving equipment such as a dragline. Also called strip mining.

    Syncline

    A down fold in rocks that resembles a U. Related Term: Fold
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    Unconformity

    A surface of erosion or nondeposition within a stratigraphic sequence that represents a gap in the geologic record. Related Term: Stratigraphic Trap
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    Weathering

    The disintegration and decomposition of rocks at or near the earth's surface. Related Term : Erosion
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    All material copyright (c) 1996 by Annabelle Foos. All rights reserved.