Term
|
Definition
| Naturally occurring, inorganic solid, with a repeating and defined crystalline structure. |
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Term
|
Definition
Low-grade regional metamorphism affecting sed. & volcanic rocks.
200-450c |
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Term
|
Definition
Outcrop pattern of a formation as it crosses a valley forms a V-shape.
V points in the direction that underlies the valley. |
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Term
|
Definition
| A number representing the % by weight or volume of dark-colored minerals in a rock. |
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Term
|
Definition
A fossil which identifies and dates strata in which it is found.
Combines wide geographic range w/ narrow stratigraphic occurrance. |
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Term
|
Definition
Composed of >90% mafic minerals.
Composed of primarily mafic minerals.
Composed of primarily felsic minerals. |
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Term
|
Definition
| A fossil group occurring in the same stratigraphic level. |
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Term
|
Definition
| Aquifer overlain by confining layer of low permeability. |
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Term
|
Definition
Intrinsic permeability unit.
9.87e-9 cm^2 |
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Term
|
Definition
| Distance between two formerly adjacent points on either side of a fault, measured on the fault surface. |
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Term
| Hydraulic Conductivity (K) |
|
Definition
| Capacity of a porous medium to transmit water. |
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|
Term
| Intrinsic Permeability (ki) |
|
Definition
Porous medium property which measures relative ease with which fluid can be transmitted through it under hydraulic gradient.
Pore size dependent. |
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Term
|
Definition
Global Positioning System
Measures your location on the Earth. |
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Term
|
Definition
| Downslope extension of the slide mass beyond the rupture plain. |
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|
Term
| Driving cause of eolian erosion. |
|
Definition
Airborne sand-particles (sandblasting)
Grain removal (deflation) |
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Term
|
Definition
Large accumulation of ice/snow.
Compaction and recrystallization of snow.
Permanent alpine feature. |
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Term
|
Definition
| The inclination of a plane measured in a direction NOT perpendicular to strike. |
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Term
|
Definition
| A hinge line along which a vertical cross-section may be constructed then flattened out to a horizontal or map view. |
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Term
| Parallel Stream Formation |
|
Definition
| Steep slopes with uniform gradient; generally found in newly uplifted terrains. |
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Term
|
Definition
Bumpy irregular surface of mass wasting materials.
Can contain transverse & radial cracks w/ transverse ridges. |
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Term
|
Definition
Organic layer of soil with undecomposed plant material.
Thick in humid regions while non-existant in arid regions. |
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Term
|
Definition
| Coal classification based on purity. |
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Term
|
Definition
Capacity of an aquifer to transmit water of the prevailing kinematic viscosity.
T = K b |
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Term
| State Plane Coordinate System |
|
Definition
| 2D coordinate system developed by Natl. Geodetic Survey for use in states/countries. |
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Term
|
Definition
The horizontal distance between a stratigraphic unit offset by a fault.
It is an apparent displacement. |
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Term
|
Definition
| A low angle reverse fault (45deg). |
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Term
|
Definition
| External, hard portion of invertebrate. |
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Term
|
Definition
Groundwater that flows beneath the bed or alluvial plain of a surface stream.
Noteworthy in arid regions. |
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Term
|
Definition
| unit of pressure; approx. 1atm or 0.1MPa |
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|
Term
| Storativity or Storage Coefficient (S) |
|
Definition
Vol. of water that a permeable unit discharges or intakes per unit surface area of the aquifer per unit change in head.
Unconfined aquifer: storage = specific yield |
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Term
|
Definition
| Shallow hydrothermal system. |
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Term
|
Definition
| A major downwarp of crust in which sediments accumulate. |
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Term
|
Definition
| The process that produces coal of an increasing rank. |
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Term
|
Definition
| Intergrowth of ≥2 crystals in a symmetrical manner. |
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Term
|
Definition
| A line described by its bearing and plunge. |
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Term
|
Definition
| Mineral replacement process by hydrothermal fluids. New mineral w/ different composition grows inside older mineral. |
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Term
|
Definition
| Mineral sequence of crystal growth during crystallization of magma. |
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Term
|
Definition
| Metamorphosed fine-grained sedimentary rock, i.e. mudstone or siltstone. |
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Term
|
Definition
Zone of illuviation.
Rich in Fe & Al clay and organic compounds. |
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Term
|
Definition
Location where geologic feature (i.e. fossils) first located.
Contains type section. |
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Term
|
Definition
| A general term for the vertical angle between horizontal and a plane or line, measured downward. |
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Term
|
Definition
| An ore deposit which originates later than the enclosing host rock. |
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Term
|
Definition
Naturally occurring deposits in such amts. or concentrations to be minable now or in the future.
Contains reserves. |
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Term
|
Definition
| The orientation in space. |
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Term
|
Definition
| How close a measurement conforms with a standard or accepted value. |
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Term
|
Definition
| The degree of arrangement or consistency of repeated measurements. |
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Term
|
Definition
Chemical variation within a crystal.
Characteristic of feldspar.
High temp. core, low temp. rim. |
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Term
|
Definition
| Geologic dating abbreviation, 1 billion years. |
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Term
|
Definition
Zone of eluviation.
Mixture of organics & mineral materials.
Fe & Al clay and organic compounds have been leached out. |
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Term
|
Definition
Substratum
Little effect from soil-forming processes.
In humid environs, thicker.
In arid environs., thin & closer to surface. |
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Term
|
Definition
Introduction of, or replacement by, pyrite.
Common hydrothermal alteration process. |
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Term
|
Definition
| Demarcation between in-situ groundmass and landslide mass. |
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Term
|
Definition
| A saturated geologic unit w/ sufficient permeability to transmit water to wells/springs. |
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Term
|
Definition
| The vertical angle between a line and horizontal. |
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Term
|
Definition
| Pertaining to the action and mineral products of hot water. |
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Term
|
Definition
| Angle between strike and apparent dip direction. |
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Term
|
Definition
| The angle measured in a specific plane, between a line and horizontal. |
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Term
|
Definition
| Inclination of the line of greatest slope of an inclined plane, measured perpendicular to strike. |
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Term
|
Definition
| The bearing of the vertical plane containing a line. |
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Term
|
Definition
| Bearing of a horizontal line in an inclined plane. |
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Term
|
Definition
| Representation of angular relationship between planes and lines. |
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Term
|
Definition
| Economically undesirable rock or mineral agg. in an orebody. |
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Term
|
Definition
| The area within which the potentiometric surface is lowered by withdrawl or raised by injection, of water through a well. |
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Term
|
Definition
descriptors of mineral grain size in volcanic rx.
Fine grained, rapid cooling, extrusive.
//
Coarse grained, slow cooling, intrusive. |
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Term
|
Definition
| Oceanic part of a geosyncline, characterized by volcanism associated with clastic sedimentation. |
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Term
|
Definition
| Metamorphism associated with igneous intrusion. |
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|
Term
|
Definition
|
|
Term
|
Definition
| A mineral deposit confined to a single stratigraphic unit. |
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Term
|
Definition
Deposits that are economically available and may be extracted profitably.
Subset of resources. |
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Term
|
Definition
| A specific type of stratabound deposit in which the ore constitutes a layer(s) in the rock. |
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Term
|
Definition
| A plant or animal that is attached and cannot move, i.e. barnacles. |
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Term
|
Definition
| The bearing of the vertical plane containing the apparent dip angle. |
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Term
|
Definition
| The horizontal angle between a line and specified coordinate direction, usually N or S. |
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Term
|
Definition
Dip-slip fault in which hanging wall has dropped relative to the foot wall.
δ = 45° - 90° |
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Term
|
Definition
| 2D representation of flow lines and equipotentials. |
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Term
|
Definition
| The amount of precipitation appearing in surface waters. |
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Term
|
Definition
| Water derived from magmatic sources; thought to be arriving at earths surface for the first time. |
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Term
|
Definition
| Physical and/or chemical changes to sediments undergoing lithification and compaction. |
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|
Term
|
Definition
Negatively charged ion
//
Positively charged ion. |
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|
Term
|
Definition
Characteristic of a mineral to exist in >1 crystalline structure form.
(andalusite/kyanite/silliminite) |
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|
Term
|
Definition
| Group of minerals that compose a rock. |
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Term
|
Definition
Zone of alteration in contact metamorphism.
"Baked zone" |
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Term
|
Definition
| Surface within unconfined groundwater where hydraulic pressure = atmospheric pressure. |
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Term
|
Definition
| Amount of soil moisture or water content held in the soil after excess water has drained away. |
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Term
|
Definition
| Minerals w/ SiO4 tetrahedra. |
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|
Term
|
Definition
The originally described strata which constitute stratigraphic unit to which other units are compared.
Greatest thickness w/ top and bottom exposed. |
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Term
|
Definition
|
|
Term
|
Definition
| Elevation to which confined aquifer water will rise in a well. |
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Term
|
Definition
| Lowest part of the aeration zone above the water table holding some water in pore spaces. |
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Term
|
Definition
| Stream pattern of lower gradient hillsides with gentle/moderate slopes, which are generally older and not recently uplifted. |
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Term
|
Definition
| Stream pattern seen in jointed rock areas (i.e. Appalachia). Confluence ~90°. |
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|
Term
|
Definition
| Undisturbed in-place material above a landslide headscarpe. |
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|
Term
|
Definition
A type of unconformity formed from an older igneous body in contact with younger sediments.
Indicates missing time after igneous intrusion. |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Object mass per volume occupied. |
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|
Term
|
Definition
| Hydroaluminocilicate mineral group, analogous to feldspars. Na, Ca, K rich. |
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|
Term
|
Definition
| The origin location from which constituent minerals of a sedimentary rock or facies are derived. |
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Term
|
Definition
| A series of minerals w/ identical structure which contain ≥2 elements over a proportion range. |
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Term
|
Definition
Widespread metamorphism w/ higher temperatures and pressures.
3-10MPa, 400-800°C |
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|
Term
|
Definition
| A particular rock unit characterized by specific lithology and/or stratigraphic position. |
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|
Term
|
Definition
Any change in mineral composition of a rock caused by physical or chemical means.
Hydrothermal fluids.
Milder and more localized than metamorphism. |
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Term
|
Definition
| Stream pattern seen on stratocone volcanos w/ steep, uniform gradient. |
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|
Term
|
Definition
| The break in slope which marks uppermost portion of a landslide mass. |
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|
Term
|
Definition
| Intensity or rank of metamorphism measured by degree/difference between parent and daughter rock. |
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|
Term
|
Definition
Rock unit formed during specific period of time.
A reference point for other similar-aged rocks. |
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Term
|
Definition
| Mappable area of restricted park of a rock body with different fossils/lithology from other continuous beds deposited at the same time. |
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Term
|
Definition
| The amount of horizontal displacement on a fault plane. |
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Term
|
Definition
| A set of metamorphic mineral assemblages which reached chemical equilibrium during metamorphism within a specific P/T condition set. |
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Term
|
Definition
| Unconfined groundwater separated from an underlying groundwater body by an unsaturated zone. |
|
|
Term
|
Definition
| A mineral deposit formed contemporaneously with, and by the same process as, the host rock. |
|
|
Term
|
Definition
| The average quantity or % of ore mineral content in an ore body. |
|
|
Term
| USA regions of Karst Topography |
|
Definition
Central FL
SW MI
W KY
TN
Atlantic Coastal Plain |
|
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Term
|
Definition
| The width of an outcrop, as measured in map view, perpendicular to strike. |
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Term
|
Definition
| Global Information System; computer-based mapping and visualizing tool. |
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|
Term
|
Definition
| A general fault term in which movement is parallel to fault plane dip, i.e. normal, reverse, listric faulting. |
|
|
Term
|
Definition
| A low-angle normal fault associated w/ regional extension, often w/ large displacements of strata. |
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|
Term
|
Definition
| Ratio of the V.h2o a soil/rock can retain against gravity drainage to the V.total of the soil/rock, as a % |
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|
Term
|
Definition
| Area where water infiltrates downward in to the saturated zone. |
|
|
Term
|
Definition
| Water trapped in the pores of sedimentary rock at time of deposition; "fossil water". |
|
|
Term
|
Definition
| A "window into rocks underlying a thrust fault. |
|
|
Term
| Single Point Resistivity log |
|
Definition
| A log measuring resistivity using two electrodes, having a limited area 5-10x electrode diameter. |
|
|
Term
|
Definition
| Vertical slip plane of lateral movement; movement is parallel to fault strike. |
|
|
Term
| Rock Quality Designation (RQD) |
|
Definition
| A measure of intactness of a rock core, relating to % of intact core vs. total core. |
|
|
Term
|
Definition
Largest classification of petroleum resource; regional.
>500M barrels recoverable
or
>3.5T ft^3 natural gas. |
|
|
Term
|
Definition
| Coarse crystalline (phaneritic), which form in large igneous intrusions at depth. |
|
|
Term
|
Definition
| Stream "movement" in low gradient floodplain area. |
|
|
Term
|
Definition
| Dependent on slope, underlying geology, and presence of groundwater. |
|
|
Term
|
Definition
| A surface which implies uplift and erosion of sediment; a "records gap" in geologic deposition. |
|
|
Term
|
Definition
| Ratio (%) of theoretical drawdown to actual drawdown measured in a well. |
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|
Term
|
Definition
| Igneous rock description feat. large grained minerals w/in a fine grained matrix. |
|
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Term
|
Definition
| Ratio of V.h2o drained due to gravity to V.total of the soil/rock |
|
|
Term
|
Definition
| An Fe-bearing weathered product overlying a sulfide deposit. |
|
|
Term
|
Definition
| The process by which elements move away from an enriched ore zone. |
|
|
Term
|
Definition
| A thrust fault with no surficial exposure. |
|
|
Term
|
Definition
Irregular surface w/ no predictable pattern.
Typically seen in glacial/karst terrain. |
|
|
Term
|
Definition
| Thick-walled barrel sampler obtains disturbed soil samples (soft clay to sand); used in the Standard Penetration Test. |
|
|
Term
Intrusive Rx
//
Extrusive Rx |
|
Definition
Coarse grained, slow cooling of emplaced magma.
//
Fine grained, rapid cooling of erupted magma/lava. |
|
|
Term
|
Definition
Joints and faults in the subsurface influence stream pattern development heavily.
Unjointed rock typically more resistant.
Common in the Adirondack Mtns. |
|
|
Term
|
Definition
| Chief method of deep borehole drilling. |
|
|
Term
|
Definition
| An aquifer having a water table. |
|
|
Term
| Spontaneous Potential (SP) Log |
|
Definition
| Borehole log of naturally occurring potentials developed between the borehole fluid, formation water, and surrounding rock materials. |
|
|
Term
| Standard Penetration Test (SPT) |
|
Definition
Test which measures resistance to penetration cone in to soils.
Number of hammer blows to a 30" long split spoon correlates to soil characteristics. |
|
|
Term
|
Definition
| Device used to measure soil matrix potential. Used to help determine irrigation needs and plant water consumption. |
|
|
Term
|
Definition
| Shallow (<20ft) method of excavating in-situ soils to determine characteristics of subsurface. |
|
|
Term
|
Definition
| Ease with which soil/rock can be mechanically excavated. |
|
|
Term
|
Definition
| Aquifer test made by adding or removing a small amount of water. |
|
|
Term
|
Definition
| Thin-walled push tube sampler to obtain undisturbed samples of cohesive soils. |
|
|
Term
| Eolian depositional features |
|
Definition
Ripples
Sand Drift / Shadow
Dunes
Sand Levee |
|
|
Term
|
Definition
| Physical measurements of the width of the uncased borehole; helps to identify unconsolidated strata beds. |
|
|
Term
|
Definition
Q = K i A
The equation describing groundwater flow (gal per "time") |
|
|
Term
| Eolian erosional features |
|
Definition
Yardang
Ventifacts
Pedestal Rock
Blowout
Desert Pavement |
|
|
Term
|
Definition
Based on: Rock type & strength
Joint & Fracture pattern
Tidal Swing
Continental Shelf extent/depth |
|
|
Term
|
Definition
Stalactite - grips the ceiling, point down
//
Stalagmite - points up from the floor |
|
|
Term
|
Definition
| Global Positioning System radio sensor that records exact position on Earth. |
|
|
Term
|
Definition
A log which makes quantitive measurements of the specific resistance of a material to the flow of an electrical current.
Used in conjunction w/ SP logs in boreholes. |
|
|
Term
|
Definition
| A test made by pumping a well for a specific period of time and observing change in hydraulic head of the aquifer. |
|
|
Term
|
Definition
| Lowest part of a mass wasting slide w/ arcuate shape after moving over original terrain. |
|
|
Term
|
Definition
| Radioactive log on natural radiation intensity of strata in a borehole after neutron bombardment. |
|
|
Term
|
Definition
Collection device for pore space groundwater.
Used to determine soluble constituents. |
|
|
Term
| Seismic Reflection survey |
|
Definition
| Geophysical survey method of seismic wave travel times through various-densitied materials. |
|
|
Term
|
Definition
| American Society for Testing and Materials Intl. |
|
|
Term
|
Definition
| Screw-like device used for shallow drilling practices (<200ft). Brings up disturbed soil cuttings. |
|
|
Term
|
Definition
| The science of recording & analyzing measurements of physical downhole strata properties. |
|
|
Term
|
Definition
Groundwater potentiometric surface depression around an actively pumped well.
Defined as the wells "area of influence". |
|
|
Term
|
Definition
| Pipe lowered and cemented in a borehole to prevent caving or fluid migration. |
|
|
Term
|
Definition
Light detection and radar.
Remote sensing method to record topography changes. Unaffected by vegetation. |
|
|
Term
|
Definition
| Aquifer test used to determine permeability of isolated rock. |
|
|
Term
|
Definition
Most widespread mineral group of the Earths crust.
Framework silicate group. |
|
|
Term
|
Definition
| Perpendicular distance between top and bottom of a geologic unit. |
|
|
Term
|
Definition
| Replacement of CaCO3 to MgCO3 in limestone; changes limestone to dolomite. |
|
|
Term
|
Definition
| A log that makes measurements of formations electrical resistivity sing 4 electrodes set up w/ 16-64" spacing. |
|
|
Term
|
Definition
| The angle between true North and magnetic North. |
|
|
Term
|
Definition
| Fine-grained crystalline (aphanetic) or glassy in texture, occur from volcanic surface activity. Explosive or extruded as lava. |
|
|
Term
|
Definition
| Lime-bearing siliceous rock produced by the metamorphic alteration of limestone or dolomite. |
|
|
Term
|
Definition
| Line perpendicular to a plane; represented as a stereonet point. |
|
|
Term
|
Definition
| Object used in a cone penetration test to measure soil insertion resistance. |
|
|
Term
|
Definition
| Silver, Gold, or metals of the Platinum Group Elements; economically significant. |
|
|
Term
|
Definition
| Degree of progressive diagenesis of peat (coalification). |
|
|
Term
|
Definition
| Vertical distance from groundsurface downward to a feature of interest. |
|
|
Term
|
Definition
| A sheet of rock that has moved horizontal over neighboring strata as a result of an overthrust or folding |
|
|
Term
|
Definition
| % of V.total of soil/rock that consists of interconnected pore space. |
|
|
Term
|
Definition
| In-site test to determine soil suitability for a leachfield. |
|
|
Term
|
Definition
| Tool to measure groundwater pressure and elevation in a drilled monitor hole. |
|
|
Term
| 4 necessary conditions for karst terrain development |
|
Definition
1) Soluble rock @/near surface.
2) Dense jointed, thin bedded.
3) Entrenched valleys below uplands.
4) Moderate to abundant rainfall. |
|
|
Term
|
Definition
| Property of porous soil/rock for transmitting a fluid. |
|
|
Term
Vadose zone
or
Zone of aeration |
|
Definition
| Subsurface zone containing water under pressure < atmospheric pressure. |
|
|
Term
|
Definition
| Area where subsurface water is discharged to land. |
|
|
Term
|
Definition
| Rate of change in total head per unit of distance of flow in a given direction. |
|
|
Term
|
Definition
| Region drained by a stream or body of water, or a drainage divide. |
|
|
Term
|
Definition
| Percentage of the bulk volume of soil/rock that is occupied by void space. |
|
|
Term
|
Definition
unit of measurement of hydraulic conductivity (gal per day / ft^2).
Flow Rate |
|
|
Term
|
Definition
| Solid-state change in composition of a mineral via diffusion. |
|
|
Term
|
Definition
| Near-surface process of mineral deposition, in which metals are leached by acidic solutions, carried downwards and precipitated, enriching the sulfide minerals already present. |
|
|
Term
|
Definition
Measure of fluid potential energy, w/ respect to given datum.
In practice, the elv. to which water raises as a result of reservoir pressure. |
|
|
Term
|
Definition
| An outlier of a thrust sheet completely surrounded by the exposed footwall. |
|
|
Term
|
Definition
| Amount of vertical displacement on a fault plane. |
|
|
Term
|
Definition
| Block which underlies a non-vertical fault plane. |
|
|
Term
|
Definition
| Amount of water that an aquifer releases from storage, per unit mass or volume of aquifer, per unit change in hydraulic head, while remaining fully saturated. |
|
|
Term
|
Definition
An overall analysis of metal in ore.
Composition, purity, weight, and other properties of economic interest. |
|
|
Term
|
Definition
| Graphic record of subsurface strata properties in a borehole as a function of depth. |
|
|
Term
|
Definition
| 1 million years abbreviation |
|
|
Term
|
Definition
Solution of old minerals w/ deposition of new minerals via interstital fluids.
Mineral replacement via hydrothermal fluids |
|
|
Term
|
Definition
| Fault block which overlies a non-vertical fault plane. |
|
|
Term
|
Definition
| Syndepositional extensional faulting. Throw increases w/ depth. |
|
|
Term
Transgression
//
Regression |
|
Definition
Advance of sea on to land (ls-sh-ss sequence).
//
Withdrawl of sea from land (ss-sh-ls sequence) |
|
|
Term
|
Definition
A fault with a curved fault plane.
Steeply dipping near surface, becoming flatter at depth.
May be normal or reverse. |
|
|
Term
|
Definition
| A well-defined, easily identifiable strata which is distinctive enough to be useful in correlation in mapping. |
|
|
Term
|
Definition
| A fault in which movement is not parallel to the strike or dip of the fault plane. |
|
|
Term
|
Definition
| Horizontal component of displacement measured perpendicular to the strike of the disrupted unit. |
|
|
Term
|
Definition
| The introduction of, or replacement by, silica. |
|
|
Term
|
Definition
| Extraction of ore in an underground mine by working laterally in the plain of the vein. |
|
|
Term
|
Definition
| Chemical product of exhalation; deposition formed by interaction of volcanic-derived water and sea water w/ adjacent rock. |
|
|
Term
|
Definition
Inverse log function of the basic or acidic nature of a fluid.
Hydrogen ion activity in a solution. |
|
|
Term
|
Definition
| Relatively mobile element whose signature can be used to find a deposit of greater value/importance. |
|
|
Term
|
Definition
Common and chemically active metal, which can oxidize or corrode easily.
An industrial non-ferrous metal, i.e. Cu, Pb, Zn, Ni. |
|
|
Term
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Definition
| Angle from the horizontal down to the slope. |
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Term
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Definition
A dip-slip fault in which the hanging wall has moved up relative to the footwall.
Fault dip: 45° ≤ δ ≤ 90° |
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Term
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Definition
Cone Penetration Test
used to measure soil resistance to cone penetration. |
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Term
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Definition
| Amount of water level drop due to well pumping. |
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Term
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Definition
| Borehole transitional zone located at flushed and uninvaded zone. |
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Term
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Definition
Interferometric Synthetic Aperture Radar
Remote sensing for ground deformation (i.e. subsidence). |
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Term
| Ground Penetrating Radar (GPR) |
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Definition
Application of radar/radio waves to the subsurface. Good for ≤100ft depth.
Low freq. = deeper
Higher freq. = shallow |
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Term
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Definition
| A series of measurements made by a gravimeter @ different field locations to determine density distribution. |
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Term
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Definition
American Petroleum Institute
A gamma ray unit of measurement in gamma logs. |
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Term
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Definition
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Term
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Definition
Measure of natural strata radioactivity down borehole.
Shale w/ high γ-value. |
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