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NARROW
Format
Article Type
Journal
Publisher
Section
GeoRef Subject
-
all geography including DSDP/ODP Sites and Legs
-
Asia
-
Far East
-
China
-
Xinjiang China
-
Junggar (1)
-
-
-
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Siberia (1)
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-
Atlantic Ocean (1)
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Canada
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Western Canada
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British Columbia (3)
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Europe
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Western Europe
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United Kingdom (1)
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Mexico
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Baja California Mexico (1)
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-
North America
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Appalachian Basin (1)
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Gulf Coastal Plain (1)
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Michigan Basin (1)
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Western Interior (1)
-
-
Permian Basin (7)
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San Juan Basin (1)
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United States
-
Alabama (1)
-
Anadarko Basin (25)
-
Ardmore Basin (4)
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Arkansas (4)
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Arkoma Basin (10)
-
Central Basin Platform (2)
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Cherokee Basin (1)
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Colorado
-
Mahogany Zone (1)
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-
Delaware Basin (2)
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Illinois (1)
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Iowa (1)
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Kansas
-
Comanche County Kansas (1)
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Harper County Kansas (1)
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Kiowa County Kansas (1)
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Osage County Kansas (1)
-
-
Louisiana (2)
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Michigan (1)
-
Midcontinent (2)
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Mississippi (1)
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Missouri (2)
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Montana
-
Phillips County Montana (1)
-
-
Nemaha Ridge (1)
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New Jersey (1)
-
New Mexico (2)
-
New York (1)
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North Dakota (1)
-
Ohio (1)
-
Oklahoma
-
Alfalfa County Oklahoma (1)
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Arbuckle Mountains (5)
-
Beckham County Oklahoma (1)
-
Blaine County Oklahoma (1)
-
Canadian County Oklahoma (5)
-
Carter County Oklahoma (3)
-
Dewey County Oklahoma (1)
-
Garfield County Oklahoma (1)
-
Grant County Oklahoma (1)
-
Johnston County Oklahoma (1)
-
Kay County Oklahoma (1)
-
Kingfisher County Oklahoma (3)
-
Kiowa County Oklahoma (1)
-
Lincoln County Oklahoma (3)
-
Logan County Oklahoma (3)
-
Murray County Oklahoma (3)
-
Oklahoma County Oklahoma (1)
-
Payne County Oklahoma (2)
-
Pittsburg County Oklahoma (1)
-
Pontotoc County Oklahoma (7)
-
Pottawatomie County Oklahoma (3)
-
Seminole County Oklahoma (1)
-
Stephens County Oklahoma (1)
-
Wichita Mountains (2)
-
Wichita Uplift (3)
-
Woods County Oklahoma (1)
-
-
Ouachita Mountains (2)
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Ozark Mountains (1)
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Pennsylvania (1)
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Powder River basin (1)
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Southern Oklahoma Aulacogen (2)
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Texas
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Crane County Texas (2)
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Fort Worth Basin (1)
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Midland Basin (3)
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Pecos County Texas (3)
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Reeves County Texas (2)
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West Texas (6)
-
Winkler County Texas (1)
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Wise County Texas (1)
-
-
Trans-Pecos (1)
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West Virginia
-
Marshall County West Virginia (1)
-
-
Wyoming (1)
-
-
-
commodities
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bitumens
-
asphalt (3)
-
-
brines (1)
-
energy sources (4)
-
metal ores
-
base metals (1)
-
lead ores (1)
-
lead-zinc deposits (1)
-
zinc ores (1)
-
-
mineral deposits, genesis (1)
-
oil and gas fields (10)
-
petroleum
-
natural gas
-
shale gas (4)
-
-
shale oil (6)
-
-
-
elements, isotopes
-
carbon
-
C-13/C-12 (4)
-
organic carbon (4)
-
-
halogens
-
iodine
-
I-129 (1)
-
-
-
hydrogen (2)
-
isotope ratios (5)
-
isotopes
-
radioactive isotopes
-
I-129 (1)
-
Pb-206/Pb-204 (1)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (1)
-
-
stable isotopes
-
C-13/C-12 (4)
-
Pb-206/Pb-204 (1)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (1)
-
-
-
metals
-
actinides
-
uranium (1)
-
-
alkali metals
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potassium (3)
-
-
alkaline earth metals
-
calcium (1)
-
strontium (1)
-
-
aluminum (4)
-
lead
-
Pb-206/Pb-204 (1)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (1)
-
-
molybdenum (3)
-
nickel (1)
-
platinum group
-
iridium (1)
-
-
titanium (3)
-
vanadium (2)
-
zirconium (3)
-
-
oxygen (1)
-
phosphorus (1)
-
silicon (3)
-
trace metals (1)
-
-
fossils
-
burrows (1)
-
Chordata
-
Vertebrata (1)
-
-
Invertebrata
-
Mollusca
-
Cephalopoda (1)
-
-
Porifera (1)
-
Protista
-
Radiolaria (1)
-
-
Vermes
-
scolecodonts (1)
-
-
-
microfossils
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Conodonta
-
Polygnathus (1)
-
-
scolecodonts (1)
-
-
palynomorphs (2)
-
Plantae
-
algae
-
Chlorophyta
-
Tasmanites (1)
-
-
Coccolithophoraceae (1)
-
diatoms (1)
-
-
-
-
geochronology methods
-
fission-track dating (1)
-
paleomagnetism (2)
-
Rb/Sr (1)
-
thermochronology (1)
-
-
geologic age
-
Cenozoic
-
Tertiary
-
Paleogene
-
Eocene
-
Green River Formation (1)
-
-
-
-
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Mowry Shale (1)
-
-
Upper Cretaceous
-
Gulfian
-
Eagle Ford Formation (3)
-
-
Lewis Shale (1)
-
Niobrara Formation (1)
-
-
-
Jurassic
-
Bazhenov Formation (1)
-
Upper Jurassic
-
Haynesville Formation (5)
-
Kimmeridge Clay (2)
-
-
-
Triassic
-
Lower Triassic (1)
-
Middle Triassic
-
Doig Formation (1)
-
-
Montney Formation (1)
-
Upper Triassic
-
Lockatong Formation (1)
-
-
-
-
Paleozoic
-
Arbuckle Group (1)
-
Cambrian (2)
-
Carboniferous
-
Lower Carboniferous
-
Dinantian (1)
-
-
Mississippian
-
Barnett Shale (9)
-
Boone Formation (1)
-
Lower Mississippian
-
Lodgepole Formation (1)
-
Osagian
-
Burlington Limestone (1)
-
-
-
Upper Mississippian
-
Chesterian (2)
-
Fayetteville Formation (3)
-
Meramecian (1)
-
-
-
Pennsylvanian
-
Middle Pennsylvanian
-
Atokan
-
Atoka Formation (2)
-
-
Desmoinesian
-
Cherokee Group (1)
-
Spiro Sandstone (1)
-
-
-
Morrow Formation (1)
-
Wapanucka Limestone (1)
-
-
Springer Formation (2)
-
-
Chattanooga Shale (2)
-
Devonian
-
Lower Devonian (1)
-
Middle Devonian
-
Givetian (1)
-
Marcellus Shale (4)
-
-
Thirtyone Formation (1)
-
Upper Devonian
-
Frasnian (1)
-
Huron Member (1)
-
Ohio Shale (3)
-
-
-
Hunton Group (10)
-
New Albany Shale (1)
-
Ordovician
-
Lower Ordovician
-
Ellenburger Group (1)
-
-
Middle Ordovician
-
Bromide Formation (1)
-
Simpson Group (2)
-
-
Montoya Group (1)
-
Upper Ordovician (1)
-
Viola Limestone (2)
-
-
Permian
-
Guadalupian (1)
-
Lower Permian
-
Cisuralian (1)
-
Leonardian
-
Bone Spring Limestone (1)
-
-
Wolfcampian (4)
-
-
Upper Permian (1)
-
-
Silurian
-
Fusselman Dolomite (1)
-
Lower Silurian (1)
-
-
upper Paleozoic
-
Antrim Shale (2)
-
Bakken Formation (5)
-
-
Woodford Shale (83)
-
-
Precambrian
-
upper Precambrian
-
Proterozoic
-
Mesoproterozoic (1)
-
Neoproterozoic (1)
-
-
-
-
-
metamorphic rocks
-
turbidite (3)
-
-
minerals
-
carbonates
-
magnesite (1)
-
norsethite (1)
-
-
oxides
-
magnetite (1)
-
-
phosphates
-
apatite (1)
-
-
silicates
-
framework silicates
-
feldspar group
-
alkali feldspar
-
K-feldspar (1)
-
-
-
silica minerals
-
opal
-
opal-A (1)
-
opal-CT (1)
-
-
quartz (3)
-
-
-
sheet silicates
-
clay minerals
-
smectite (1)
-
-
illite (1)
-
mica group
-
biotite (1)
-
-
-
-
sulfides
-
sphalerite (1)
-
-
-
Primary terms
-
absolute age (1)
-
Asia
-
Far East
-
China
-
Xinjiang China
-
Junggar (1)
-
-
-
-
Siberia (1)
-
-
Atlantic Ocean (1)
-
bitumens
-
asphalt (3)
-
-
brines (1)
-
Canada
-
Western Canada
-
British Columbia (3)
-
-
-
carbon
-
C-13/C-12 (4)
-
organic carbon (4)
-
-
Cenozoic
-
Tertiary
-
Paleogene
-
Eocene
-
Green River Formation (1)
-
-
-
-
-
Chordata
-
Vertebrata (1)
-
-
clay mineralogy (2)
-
data processing (6)
-
deformation (4)
-
diagenesis (6)
-
earthquakes (2)
-
economic geology (9)
-
energy sources (4)
-
Europe
-
Western Europe
-
United Kingdom (1)
-
-
-
faults (8)
-
folds (2)
-
fractures (7)
-
geochemistry (5)
-
geochronology (2)
-
geophysical methods (18)
-
heat flow (3)
-
hydrogen (2)
-
Invertebrata
-
Mollusca
-
Cephalopoda (1)
-
-
Porifera (1)
-
Protista
-
Radiolaria (1)
-
-
Vermes
-
scolecodonts (1)
-
-
-
isotopes
-
radioactive isotopes
-
I-129 (1)
-
Pb-206/Pb-204 (1)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (1)
-
-
stable isotopes
-
C-13/C-12 (4)
-
Pb-206/Pb-204 (1)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (1)
-
-
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Mowry Shale (1)
-
-
Upper Cretaceous
-
Gulfian
-
Eagle Ford Formation (3)
-
-
Lewis Shale (1)
-
Niobrara Formation (1)
-
-
-
Jurassic
-
Bazhenov Formation (1)
-
Upper Jurassic
-
Haynesville Formation (5)
-
Kimmeridge Clay (2)
-
-
-
Triassic
-
Lower Triassic (1)
-
Middle Triassic
-
Doig Formation (1)
-
-
Montney Formation (1)
-
Upper Triassic
-
Lockatong Formation (1)
-
-
-
-
metal ores
-
base metals (1)
-
lead ores (1)
-
lead-zinc deposits (1)
-
zinc ores (1)
-
-
metals
-
actinides
-
uranium (1)
-
-
alkali metals
-
potassium (3)
-
-
alkaline earth metals
-
calcium (1)
-
strontium (1)
-
-
aluminum (4)
-
lead
-
Pb-206/Pb-204 (1)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (1)
-
-
molybdenum (3)
-
nickel (1)
-
platinum group
-
iridium (1)
-
-
titanium (3)
-
vanadium (2)
-
zirconium (3)
-
-
metasomatism (2)
-
Mexico
-
Baja California Mexico (1)
-
-
mineral deposits, genesis (1)
-
North America
-
Appalachian Basin (1)
-
Gulf Coastal Plain (1)
-
Michigan Basin (1)
-
Western Interior (1)
-
-
oil and gas fields (10)
-
orogeny (1)
-
oxygen (1)
-
paleogeography (1)
-
paleomagnetism (2)
-
Paleozoic
-
Arbuckle Group (1)
-
Cambrian (2)
-
Carboniferous
-
Lower Carboniferous
-
Dinantian (1)
-
-
Mississippian
-
Barnett Shale (9)
-
Boone Formation (1)
-
Lower Mississippian
-
Lodgepole Formation (1)
-
Osagian
-
Burlington Limestone (1)
-
-
-
Upper Mississippian
-
Chesterian (2)
-
Fayetteville Formation (3)
-
Meramecian (1)
-
-
-
Pennsylvanian
-
Middle Pennsylvanian
-
Atokan
-
Atoka Formation (2)
-
-
Desmoinesian
-
Cherokee Group (1)
-
Spiro Sandstone (1)
-
-
-
Morrow Formation (1)
-
Wapanucka Limestone (1)
-
-
Springer Formation (2)
-
-
Chattanooga Shale (2)
-
Devonian
-
Lower Devonian (1)
-
Middle Devonian
-
Givetian (1)
-
Marcellus Shale (4)
-
-
Thirtyone Formation (1)
-
Upper Devonian
-
Frasnian (1)
-
Huron Member (1)
-
Ohio Shale (3)
-
-
-
Hunton Group (10)
-
New Albany Shale (1)
-
Ordovician
-
Lower Ordovician
-
Ellenburger Group (1)
-
-
Middle Ordovician
-
Bromide Formation (1)
-
Simpson Group (2)
-
-
Montoya Group (1)
-
Upper Ordovician (1)
-
Viola Limestone (2)
-
-
Permian
-
Guadalupian (1)
-
Lower Permian
-
Cisuralian (1)
-
Leonardian
-
Bone Spring Limestone (1)
-
-
Wolfcampian (4)
-
-
Upper Permian (1)
-
-
Silurian
-
Fusselman Dolomite (1)
-
Lower Silurian (1)
-
-
upper Paleozoic
-
Antrim Shale (2)
-
Bakken Formation (5)
-
-
Woodford Shale (83)
-
-
palynomorphs (2)
-
paragenesis (3)
-
petroleum
-
natural gas
-
shale gas (4)
-
-
shale oil (6)
-
-
phosphorus (1)
-
Plantae
-
algae
-
Chlorophyta
-
Tasmanites (1)
-
-
Coccolithophoraceae (1)
-
diatoms (1)
-
-
-
Precambrian
-
upper Precambrian
-
Proterozoic
-
Mesoproterozoic (1)
-
Neoproterozoic (1)
-
-
-
-
rock mechanics (1)
-
sea-level changes (10)
-
sedimentary rocks
-
carbonate rocks
-
dolostone (2)
-
grainstone (1)
-
limestone (6)
-
packstone (1)
-
-
chemically precipitated rocks
-
chert (10)
-
-
clastic rocks
-
arenite (1)
-
black shale (10)
-
diatomite (1)
-
mudstone (15)
-
sandstone (4)
-
shale (23)
-
siltstone (1)
-
-
gas shale (6)
-
oil shale (4)
-
-
sedimentary structures
-
biogenic structures
-
bioturbation (2)
-
-
planar bedding structures
-
bedding (2)
-
laminations (1)
-
-
-
sedimentation (3)
-
sediments
-
clastic sediments
-
clay (2)
-
-
-
silicon (3)
-
stratigraphy (6)
-
structural analysis (1)
-
structural geology (1)
-
tectonics (3)
-
underground installations (1)
-
United States
-
Alabama (1)
-
Anadarko Basin (25)
-
Ardmore Basin (4)
-
Arkansas (4)
-
Arkoma Basin (10)
-
Central Basin Platform (2)
-
Cherokee Basin (1)
-
Colorado
-
Mahogany Zone (1)
-
-
Delaware Basin (2)
-
Illinois (1)
-
Iowa (1)
-
Kansas
-
Comanche County Kansas (1)
-
Harper County Kansas (1)
-
Kiowa County Kansas (1)
-
Osage County Kansas (1)
-
-
Louisiana (2)
-
Michigan (1)
-
Midcontinent (2)
-
Mississippi (1)
-
Missouri (2)
-
Montana
-
Phillips County Montana (1)
-
-
Nemaha Ridge (1)
-
New Jersey (1)
-
New Mexico (2)
-
New York (1)
-
North Dakota (1)
-
Ohio (1)
-
Oklahoma
-
Alfalfa County Oklahoma (1)
-
Arbuckle Mountains (5)
-
Beckham County Oklahoma (1)
-
Blaine County Oklahoma (1)
-
Canadian County Oklahoma (5)
-
Carter County Oklahoma (3)
-
Dewey County Oklahoma (1)
-
Garfield County Oklahoma (1)
-
Grant County Oklahoma (1)
-
Johnston County Oklahoma (1)
-
Kay County Oklahoma (1)
-
Kingfisher County Oklahoma (3)
-
Kiowa County Oklahoma (1)
-
Lincoln County Oklahoma (3)
-
Logan County Oklahoma (3)
-
Murray County Oklahoma (3)
-
Oklahoma County Oklahoma (1)
-
Payne County Oklahoma (2)
-
Pittsburg County Oklahoma (1)
-
Pontotoc County Oklahoma (7)
-
Pottawatomie County Oklahoma (3)
-
Seminole County Oklahoma (1)
-
Stephens County Oklahoma (1)
-
Wichita Mountains (2)
-
Wichita Uplift (3)
-
Woods County Oklahoma (1)
-
-
Ouachita Mountains (2)
-
Ozark Mountains (1)
-
Pennsylvania (1)
-
Powder River basin (1)
-
Southern Oklahoma Aulacogen (2)
-
Texas
-
Crane County Texas (2)
-
Fort Worth Basin (1)
-
Midland Basin (3)
-
Pecos County Texas (3)
-
Reeves County Texas (2)
-
West Texas (6)
-
Winkler County Texas (1)
-
Wise County Texas (1)
-
-
Trans-Pecos (1)
-
West Virginia
-
Marshall County West Virginia (1)
-
-
Wyoming (1)
-
-
weathering (1)
-
well-logging (5)
-
-
sedimentary rocks
-
sedimentary rocks
-
carbonate rocks
-
dolostone (2)
-
grainstone (1)
-
limestone (6)
-
packstone (1)
-
-
chemically precipitated rocks
-
chert (10)
-
-
clastic rocks
-
arenite (1)
-
black shale (10)
-
diatomite (1)
-
mudstone (15)
-
sandstone (4)
-
shale (23)
-
siltstone (1)
-
-
gas shale (6)
-
oil shale (4)
-
-
siliciclastics (1)
-
turbidite (3)
-
-
sedimentary structures
-
burrows (1)
-
sedimentary structures
-
biogenic structures
-
bioturbation (2)
-
-
planar bedding structures
-
bedding (2)
-
laminations (1)
-
-
-
stratification (1)
-
-
sediments
-
sediments
-
clastic sediments
-
clay (2)
-
-
-
siliciclastics (1)
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turbidite (3)
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Woodford Shale
Lithofacies and porosity heterogeneity of Ordovician–Pennsylvanian successions of the Midland Basin: Implications for wastewater disposal reservoir potential
An empirical elastic anisotropy prediction model in self-sourced reservoir shales and its influencing factor analysis
Geochemical characteristics of oils from the Sooner Trend Anadarko Basin, Canadian, and Kingfisher Counties and South-Central Oklahoma Oil Province plays, Anadarko Basin, Oklahoma
West Texas (Permian) Super Basin, United States: Tectonics, structural development, sedimentation, petroleum systems, and hydrocarbon reserves
The Anadarko “Super” Basin: 10 key characteristics to understand its productivity
Geochemical characterization and classification of crude oils of the Permian Basin, west Texas and southeastern New Mexico
Source-rock reservoirs geochemistry of Devonian–Mississippian mudrocks in central Oklahoma
Depositional interpretation and sequence stratigraphic control on reservoir quality and distribution in the Meramecian Sooner trend Anadarko Basin, Canadian, and Kingfisher Counties (STACK) play, Anadarko Basin, Oklahoma, United States
Compositional and Diagenetic Controls on Brittleness in Organic Siliceous Mudrocks
ABSTRACT An evaluation of an integrated data set collected over the past 12 years designed to identify the parameters controlling reservoir quality and production properties in organic, siliceous mudrocks reveals the key diagenetic processes affecting the development of brittleness in siliceous mudrocks. This work was motivated by the failure of early efforts to correlate brittleness to x-ray diffraction (XRD) mineralogy. The outcome of this analysis has been the recognition of two, often overlapping, pathways to brittleness that are determined at the time of deposition by the relative proportions of clay, detrital quartz, and biogenic silica present in the original sediment and are later affected by burial history. One pathway begins with a phyllosilicate–mud-dominated sediment, and the other begins with a sediment containing common or abundant biogenic silica (opal-A). Both pathways are characterized by compactional porosity loss and both eventually include the generation of authigenic quartz cement; however, the source of that authigenic quartz is different between the two pathways. The authigenic quartz that characterizes the first pathway is developed from the illitization of smectite and is precipitated as a cement within the argillaceous matrix. This authigenic quartz is detectable along with the detrital quartz by XRD analysis. All other factors being equal, the volume of brittle, authigenic quartz cement derived from the alteration of smectite is proportional to the volume of original clay. As a result, the effectiveness of this cement to increase the brittleness of the rock may be impacted by the presence of the ductile clays. In the alternate pathway, authigenic quartz is derived from the transformation of biogenic opal-A and is independent of the amount of clay. Much of the XRD quartz volume in rocks derived from biogenic–silica-rich sediment that contained little or no detrital quartz will comprise a brittle, authigenic cement.
ABSTRACT The Devonian Woodford Shale and Cretaceous Mowry Shale consist of relatively deep (below storm wave base) intracratonic basin deposits commonly referred to as “shales” because of their dark gray to nearly black color, very fine-grained nature, pelagic fossils such as radiolarians, and common amorphous marine kerogen. These shales typically contain less than 30% detrital clay by weight and more than 50% quartz (locally up to 80%). The quartz is a mix of biogenic grains, mainly radiolarians, and authigenic silica along with some detrital quartz silt of extrabasinal origin. The authigenic silica is dominantly microcrystalline (< 1 micron) and forms a major component of the matrix in these formations, but the rocks also contain authigenic pyrite, commonly as framboids, minor carbonates including magnesite, and quartz overgrowths, but together these authigenic minerals form less than 10% of the rock. Authigenic quartz in the Woodford and Mowry samples commonly takes the form of silica nanospheres, a type of microquartz less than a half micron in diameter. Textures of this microquartz are best observed directly with a high-resolution electron microscope. In many Woodford and Mowry samples, the silica nanospheres, which tend to be associated with organic matter, form more than 50% of the rock. The large volume of the authigenic quartz, together with “floating” detrital components and the close association with pyrite framboids, indicates that the silica nanospheres formed very early, perhaps in association with microbial activity on or in the seafloor sediments. These early silica nanospheres, which are only weakly luminescent, helped create a lithified sediment during or soon after deposition. Where the silicification process ceased prior to complete silica cementation, the early silica nanospheres are associated with up to 15% interparticle microporosity. This gives the Woodford and Mowry good potential reservoir quality, at least locally. The authigenic silica nanospheres also enhance the mechanical properties and brittleness of these siliceous mudrocks to a degree much greater than the presence of the detrital quartz particles alone.
ABSTRACT Scanning electron microscopy (SEM) has revolutionized our understanding of shale petroleum systems through microstructural characterization of dispersed organic matter (OM). However, as a result of the low atomic weight of carbon, all OM appears black in SEM (BSE [backscattered electron] image) regardless of differences in thermal maturity or OM type (kerogen types or solid bitumen). Traditional petrographic identification of OM uses optical microscopy, where reflectance (%R o ), form, relief, and fluorescence can be used to discern OM types and thermal maturation stage. Unfortunately, most SEM studies of shale OM do not employ correlative optical techniques, leading to misidentifications or to the conclusion that all OM (i.e., kerogen and solid bitumen) is the same. To improve the accuracy of SEM identifications of dispersed OM in shale, correlative light and electron microscopy (CLEM) was used during this study to create optical and SEM images of OM in the same fields of view (500× magnification) under white light, blue light, secondary electron (SE), and BSE conditions. Samples ( n = 8) of varying thermal maturities and typical of the North American shale petroleum systems were used, including the Green River Mahogany Zone, Bakken Formation, Ohio Shale, Eagle Ford Formation, Barnett Formation, Haynesville Formation, and Woodford Shale. The CLEM image sets demonstrate the importance of correlative microscopy by showing how easily OM can be misidentified when viewed by SEM alone. Without CLEM techniques, petrographic data from SEM such as observations of organic nanoporosity may be misinterpreted, resulting in false or ambiguous results and impairing an improved understanding of organic diagenesis and catagenesis.