GEOLOGY 2 Flashcards
(100 cards)
1
Q
A porous sand layer or sand body filled with oil.
A
oil sand
2
Q
A quality of directional uniformity in material such that physical properties do not vary in different directions
A
isotropy
3
Q
A record of the onset and duration of the multitude of episodes of reversal of the Earth’s magnetic polarity, or geomagnetic polarity reversals
A
geomagnetic polarity time scale / GPTS
4
Q
A reduction in bed thickness resulting from onlapping stratigraphic sequences
A
pinch-out
5
Q
A relatively flat, nearly level area of sedimentary rocks in a continent that overlies or abuts the basement rocks of a craton
A
platform
6
Q
A relatively high-standing area formed by the movement of normal faults that dip away from each other.
A
horst
7
Q
A relatively impermeable rock, commonly shale, anhydrite or salt, that forms a barrier or seal above and around reservoir rock so that fluids cannot migrate beyond the reservoir
A
cap rock / seal
8
Q
A relatively low-standing fault block bounded by opposing normal faults.
A
graben
9
Q
A relatively mobile mass that intrudes into preexisting rocks
A
diapir
10
Q
A reservoir in which buoyant forces keep hydrocarbons in place below a sealing caprock
A
conventional reservoir
11
Q
A reservoir or portion of a reservoir that contains economically producible hydrocarbons
A
pay
12
Q
A rhythmic sequence of sediments deposited in annual cycles in glacial lakes
A
varve
13
Q
A rock composed chiefly (> 90%) of dolomite
A
dolostone
14
Q
A rock mass formed somewhere other than its present location, which was transported by fault movements, large-scale gravity sliding, or similar processes.
A
allochthon
15
Q
A rock rich in organic matter which, if heated sufficiently, will generate oil or gas
A
source rock
16
Q
A scientist trained in the study of the Earth
A
geologist
17
Q
A sedimentary rock and a variety of quartz made of extremely fine-grained, or cryptocrystalline, silica, also called chalcedony
A
chert
18
Q
A sedimentary rock containing a mix of clay and calcium carbonate
A
marl
19
Q
A semi-enclosed coastal environment of deposition in which a river mouth permits freshwater to contact and mix with seawater
A
estuary
20
Q
A soft, silica-rich sedimentary rock comprising diatom remains that forms most commonly in lakes and deep marine areas
A
diatomite
21
Q
A soft, soluble evaporite mineral commonly known as salt or rock salt
A
halite / salt
22
Q
A solid or nearly solid form of bitumen that can melt upon heating and contains impurities such as nitrogen, oxygen and sulfur
A
asphalt
23
Q
A stable area of continental crust that has not undergone much plate tectonic or orogenic activity for a long period
A
craton
24
Q
A subsurface body of rock having sufficient porosity and permeability to store and transmit fluids.
A
reservoir
25
A subsurface condition in which the pore pressure of a geologic formation exceeds or is less than the expected, or normal, formation pressure.
abnormal pressure
26
A subsurface oil accumulation
oil pool / accumulation / field / oil field
27
A subsurface rock that lacks contact with aquifers or meteoric water within the Earth
dry rock
28
A surface feature of the Earth that allows magma, ash and gas to erupt
volcano
29
A surface land form
formation
30
A surface of breakage, cracking or separation within a rock along which there has been no movement parallel to the defining plane
joint
31
A surface that separates older sequences from younger ones, commonly an unconformity (indicating subaerial exposure), but in limited cases a correlative conformable surface
sequence boundary
32
A surface that separates younger strata from eroded, dipping, older strata and represents a gap in the geologic record
angular unconformity
33
A system of numerous Earth-orbiting satellites that can be used to determine the location (latitude, longitude and elevation) of a receiver or station on the Earth within about 2 m [6 ft]
global positioning system / GPS
34
A telescopic surveying device used to construct surface topographic and geologic maps in the field
alidade
35
A term applied to hard rocks, or igneous and metamorphic rocks that are distinguished from sedimentary rocks because they are typically more difficult to disaggregate
hard rock
36
A test in which the pore fluid in the sample is able to flow and equilibrate to imposed pore pressure conditions; the fluid mass and volume will vary but its pressure will be constant
drained test
37
a test that in which the fluid in the sample is not able to flow and equilibrate to imposed pore pressure conditions; the fluid mass remains the same while the fluid volume and pressure will vary
undrained test
38
A thrust fault having a relatively large lateral displacement
overthrust
39
A topographic feature consisting of a large flat area at a relatively high elevation with steep sides
plateau
40
A type of anticline that is circular or elliptical rather than elongate
dome
41
A type of clay mineral from the kaolin group that forms through the weathering of feldspar and mica group minerals
kaolinite
42
A type of fault formed when the hanging wall fault block moves up along a fault surface relative to the footwall. Such movement can occur in areas where the Earth's crust is compressed
reverse fault
43
A type of fault in which the hanging wall moves down relative to the footwall, and the fault surface dips steeply, commonly from 50o to 90o.
normal fault
44
A type of fault whose surface is typically vertical or nearly so.
strike-slip fault
45
A type of fold in which the thickness of the layers remains constant when measured parallel to the axial surface and the layers have the same wave shape, but the thickness along each layer varies
similar fold
46
A type of geochemical analysis in which a rock sample is subject to controlled heating in an inert gas to or past the point of generating hydrocarbons in order to assess its quality as a source rock, the abundance of organic material in it, its thermal maturity, and the quality of hydrocarbons it might generate or have generated
pyrolisis
47
A type of hydrocarbon trap whose closure is controlled by the presence of an unconformity
unconformity trap
48
A type of metamorphic rock with shearing and granulation of minerals caused by high mechanical stress during faulting or dynamic metamorphism, typically during episodes of plate tectonic activity
cataclasite
49
A type of minor fault whose sense of displacement is similar to its associated major fault
synthetic fault
50
A type of normal fault that develops and continues to move during sedimentation and typically has thicker strata on the downthrown, hanging wall side of the fault than in the footwall
growth fault
51
A type of porosity resulting from the presence of vesicles, or gas bubbles, in igneous rock
vesicular porosity
52
A type of reverse fault in which the fault plane has a very shallow dip, typically much less than 45o
thrust fault
53
A type of secondary porosity created during diagenesis, commonly through dissolution or dolomitization or both
diagenetic porosity
54
A type of secondary porosity created through the dissolution of a preexisting constituent of a rock, such as a shell, rock fragment or grain
moldic porosity
55
A type of secondary porosity produced by the tectonic fracturing of rock
fracture porosity
56
A type of smectite clay mineral that tends to swell when exposed to water
montmorillonite
57
A type of stratigraphic trap. The termination by thinning or tapering out ("pinching out") of a reservoir against a nonporous sealing rock creates a favorable geometry to trap hydrocarbons, particularly if the adjacent sealing rock is a source rock such as a shale
pinch-out
58
A type of strike-slip fault in which the fault surface is vertical, and the fault blocks move sideways past each other
wrench fault
59
A type of structural hydrocarbon trap in which closure is controlled by the presence of at least one fault surface
fault trap
60
A type of subsurface map whose contours represent the elevation of a particular formation, reservoir or geologic marker in space, such that folds, faults and other geologic structures are clearly displayed
structure map
61
A type of topography formed in areas of widespread carbonate rocks through dissolution
karst
62
A type of woody kerogen that is relatively uniform in composition.
vitrinite
63
A variety of sealed geologic container capable of retaining hydrocarbons, formed by changes in rock type or pinch-outs, unconformities, or sedimentary features such as reefs
stratigraphic trap
64
A variety of sealed geologic structure capable of retaining hydrocarbons, such as a fault or a fold.
structural trap
65
A water-bearing portion of a petroleum reservoir with a waterdrive
aquifer
66
A wave-like geologic structure that forms when rocks deform by bending instead of breaking under compressional stress
fold
67
A wetland depositional environment in which water is present either permanently or intermittently and in which trees and large woody plants can grow but peat does not form
swamp
68
A widely-distributed carbonate mineral and chief constituent of dolostone
dolomite
69
A worldwide grid system of rectangular map coordinates that uses metric (SI) units.
Universal transverse mercator grid / UTM
70
A zone of the upper mantle in which earthquakes occur when a lithospheric plate is subducted, named in honor of seismologists Kiyoo Wadati and Hugo Benioff
Benioff zone / Wadati - Benioff zone
71
Ability of a material to undergo stress, deform, and then recover and return to its original shape after the stress ceases
elasticity
72
Also known as plate tectonics, the unifying geologic theory developed to explain observations that interactions of the brittle plates of the lithosphere with each other and with the softer underlying asthenosphere result in large-scale changes in the Earth
tectonics
73
Also known as weathered layer, a near-surface, possibly unconsolidated layer of low seismic velocity
low velocity layer
74
An abundant rock-forming mineral composed of silicon and oxygen, also called silica. Quartz sand grains are a major constituent of sandstone and other clastic sedimentary rocks
quartz
75
An accumulation, pool or group of pools of oil in the subsurface.
oil field
76
An accumulation, pool, or group of pools of hydrocarbons or other mineral resources in the subsurface
field
77
An aggregate of minerals or organic matter (in the case of coal, which is not composed of minerals because of its organic origin), or volcanic glass (obsidian, which forms a rock but is not considered a mineral because of its amorphous, noncrystalline nature).
rock
78
An analysis of the history, composition, relative ages and distribution of strata, and the interpretation of strata to elucidate Earth history
stratigraphic analysis
79
An arch-shaped fold in rock in which rock layers are upwardly convex
anticline
80
An arcuate deposit of sediment, usually sand, that occurs along the convex inner edges of the meanders of channels and builds outward as the stream channel migrates.
point bar
81
An area in which hydrocarbon accumulations or prospects of a given type occur.
exploration play / play
82
An area of deposition or the deposit formed by a flowing sediment-laden current as it enters an open or standing body of water, such as a river spilling into a gulf
delta
83
An area of exploration in which hydrocarbons have been predicted to exist in economic quantity
prospect
84
An area of surface land on which exploration or production activity occurs
lease
85
An area of the subsurface where source rock has reached appropriate conditions of pressure and temperature to generate hydrocarbons
hydrocarbon kitchen
86
An area of the subsurface where source rock has reached appropriate conditions of pressure and temperature to generate liquid hydrocarbons as opposed to gas
oil kitchen
87
An entity or property that differs from what is typical or expected, or which differs from that predicted by a theoretical model
anomaly
88
An environment from which water rarely drains that supports primarily grassy vegetation and does not form peat
marsh
89
An environment of coastal sedimentation characterized by arid or semiarid conditions above the level of high tide and by the absence of vegetation
sabkha
90
An exploration and production play type in which prospects exist below salt layers
subsalt
91
An influx of rapidly moving, sediment-laden water down a slope into a larger body of water; the suspended sediment causes the current to have a higher density than the clearer water into which it flows, hence the name
density current / turbidity current
92
An informal term used to denote a surface in or of rock, or a distinctive layer of rock that might be represented by a reflection in seismic data
horizon
93
An interaction of lithospheric plates that can result in the formation of mountain belts and subduction zones
collision
94
An interval or unit of rock differentiated from surrounding rocks on the basis of its fossil content or other features, such as faults or fractures
zone
95
An intrusive rock that invades preexisting rocks, commonly in a tabular shape that cuts vertically or nearly vertically across preexisting layers
dike / dyke
96
An occurrence of trapped hydrocarbons, an oil field
accumulation / play
97
An umbrella term for oil and natural gas that is produced by means that do not meet the criteria for conventional production
unconventional resource
98
An unusual occurrence of hydrocarbon in which molecules of natural gas, typically methane, are trapped in ice molecules
clathrate / gas hydrate / hydrate
99
An unusual occurrence of hydrocarbon in which molecules of methane are trapped in ice molecules
methane hydrate
100
Basin- or trough-shaped fold in rock in which rock layers are downwardly convex
syncline
