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NARROW
Format
Article Type
Journal
Publisher
Section
GeoRef Subject
-
all geography including DSDP/ODP Sites and Legs
-
Africa
-
Adrar des Iforas (1)
-
Central Africa
-
Angola
-
Cabinda Angola (1)
-
-
Central African Republic (3)
-
Congo (2)
-
Congo Democratic Republic (2)
-
Equatorial Guinea (1)
-
Gabon (4)
-
-
Congo Craton (1)
-
East Africa
-
Ethiopia (3)
-
Kenya (3)
-
Malawi (1)
-
Mozambique (3)
-
Sudan (1)
-
Tanzania (1)
-
Uganda (1)
-
-
Madagascar (2)
-
North Africa
-
Algeria
-
Ahaggar (1)
-
-
Atlas Mountains
-
Moroccan Atlas Mountains
-
Anti-Atlas (1)
-
-
-
Egypt (1)
-
Morocco
-
Moroccan Atlas Mountains
-
Anti-Atlas (1)
-
-
-
-
Sahara (1)
-
Senegal River (1)
-
Southern Africa
-
Lesotho (1)
-
Namibia
-
Walvis Bay Namibia (1)
-
-
South Africa
-
Witwatersrand (1)
-
-
Zimbabwe (1)
-
-
West Africa
-
Benin (5)
-
Burkina Faso (6)
-
Cameroon (4)
-
Chad (1)
-
Gambia (1)
-
Ghana (16)
-
Guinea (6)
-
Ivory Coast (67)
-
Liberia (6)
-
Mali (2)
-
Mauritania (4)
-
Niger (3)
-
Nigeria (4)
-
Nimba Mountains (1)
-
Senegal (4)
-
Sierra Leone (3)
-
Togo (4)
-
-
West African Craton (2)
-
West African Shield (2)
-
-
Asia
-
Central Asia
-
Kazakhstan
-
Aktyubinsk Kazakhstan
-
Zhamanshin Crater (1)
-
-
-
-
Far East
-
Indochina (1)
-
Indonesia (1)
-
Vietnam
-
Dalat Vietnam (1)
-
-
-
-
Atlantic Ocean
-
East Atlantic (1)
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Equatorial Atlantic (3)
-
North Atlantic
-
Gulf of Guinea (6)
-
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South Atlantic
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Falkland Plateau (1)
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-
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Atlantic Ocean Islands
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Ascension Island (1)
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Australasia
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Australia (1)
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New Zealand (1)
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Canada
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Western Canada
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Athabasca Basin (1)
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Saskatchewan (1)
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Caribbean region
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West Indies
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Antilles
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Lesser Antilles
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Martinique (1)
-
-
-
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Commonwealth of Independent States
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Kazakhstan
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Aktyubinsk Kazakhstan
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Zhamanshin Crater (1)
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-
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-
Europe
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Central Europe (1)
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Western Europe
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France (1)
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Scandinavia
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Denmark (1)
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-
-
-
Indian Ocean
-
Exmouth Plateau (1)
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Mozambique Channel (1)
-
-
Indian Ocean Islands
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Madagascar (2)
-
Mauritius (1)
-
-
North America
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Canadian Shield
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Superior Province (1)
-
-
-
South America
-
Brazil (2)
-
Guiana Shield (2)
-
-
United States
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New Mexico
-
Otero County New Mexico (1)
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Socorro County New Mexico (1)
-
-
North Carolina (1)
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Texas (1)
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Washington (1)
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-
-
commodities
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diamond deposits (2)
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energy sources (1)
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glass materials (2)
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metal ores
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aluminum ores (1)
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copper ores (2)
-
gold ores (5)
-
iron ores (2)
-
manganese ores (3)
-
nickel ores (3)
-
niobium ores (1)
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platinum ores (1)
-
tantalum ores (1)
-
-
mineral deposits, genesis (8)
-
mineral exploration (3)
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petroleum
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natural gas (1)
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-
placers (1)
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water resources (1)
-
-
elements, isotopes
-
carbon
-
organic carbon (2)
-
-
halogens
-
chlorine
-
chloride ion (1)
-
-
-
hydrogen
-
D/H (1)
-
-
isotope ratios (3)
-
isotopes
-
stable isotopes
-
D/H (1)
-
O-18/O-16 (1)
-
S-34/S-32 (1)
-
-
-
metals
-
actinides
-
uranium (1)
-
-
alkali metals
-
rubidium (1)
-
-
alkaline earth metals
-
calcium (1)
-
magnesium (2)
-
strontium (1)
-
-
aluminum (1)
-
copper (1)
-
gold (1)
-
iron
-
ferric iron (2)
-
ferrous iron (2)
-
-
lead (1)
-
manganese (2)
-
nickel (1)
-
platinum group
-
platinum ores (1)
-
-
rare earths (1)
-
-
oxygen
-
O-18/O-16 (1)
-
-
sulfur
-
S-34/S-32 (1)
-
-
-
fossils
-
Invertebrata
-
Arthropoda
-
Mandibulata
-
Crustacea
-
Malacostraca (1)
-
-
-
-
Cnidaria
-
Anthozoa (1)
-
-
Protista
-
Foraminifera
-
Rotaliina
-
Rotaliacea
-
Nummulitidae
-
Nummulites
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Operculina (1)
-
-
-
-
-
-
-
-
microfossils (2)
-
Plantae
-
algae
-
nannofossils (1)
-
-
-
-
geochronology methods
-
Ar/Ar (1)
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fission-track dating (3)
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K/Ar (2)
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paleomagnetism (1)
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Rb/Sr (1)
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thermochronology (1)
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thermoluminescence (1)
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U/Pb (2)
-
-
geologic age
-
Cenozoic
-
Quaternary
-
Holocene (3)
-
Pleistocene (2)
-
-
Tertiary
-
Neogene
-
Miocene (1)
-
-
Paleogene
-
Eocene (2)
-
Oligocene (1)
-
Paleocene (1)
-
-
-
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Albian (1)
-
Aptian (1)
-
-
Upper Cretaceous
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Cenomanian (1)
-
Coniacian (1)
-
Santonian (1)
-
Senonian (1)
-
Turonian (1)
-
-
-
Jurassic (1)
-
-
Paleozoic (1)
-
Precambrian
-
Archean (5)
-
upper Precambrian
-
Proterozoic
-
Paleoproterozoic
-
Birimian (11)
-
-
-
-
-
-
igneous rocks
-
igneous rocks
-
plutonic rocks
-
diabase (1)
-
gabbros (1)
-
granites
-
charnockite (2)
-
-
pegmatite (1)
-
ultramafics
-
pyroxenite
-
clinopyroxenite (1)
-
-
-
-
volcanic rocks
-
basalts
-
tholeiite (1)
-
-
glasses
-
volcanic glass (1)
-
-
pyroclastics
-
tuff (1)
-
-
-
-
-
metamorphic rocks
-
metamorphic rocks
-
amphibolites (1)
-
gneisses (2)
-
granulites (1)
-
impactites (2)
-
metaigneous rocks
-
metadiabase (1)
-
-
metasedimentary rocks (2)
-
metasomatic rocks
-
skarn (2)
-
-
metavolcanic rocks (1)
-
migmatites (1)
-
schists
-
greenstone (1)
-
-
-
turbidite (1)
-
-
meteorites
-
meteorites (1)
-
-
minerals
-
arsenides
-
gersdorffite (1)
-
-
carbonates
-
calcite (2)
-
-
minerals (3)
-
native elements
-
diamond (1)
-
-
oxides
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cryptomelane (1)
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goethite (2)
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hematite (1)
-
hydroxides
-
oxyhydroxides (1)
-
-
iron oxides (1)
-
lithiophorite (1)
-
niobates
-
columbite (1)
-
-
tantalates
-
tantalite (1)
-
-
-
phosphates
-
apatite (2)
-
crandallite (1)
-
monazite (1)
-
variscite (1)
-
-
silicates
-
chain silicates
-
pyroxene group (1)
-
-
framework silicates
-
feldspar group
-
alkali feldspar
-
perthite (1)
-
-
-
silica minerals
-
quartz (1)
-
-
-
orthosilicates
-
nesosilicates
-
olivine group
-
forsterite (1)
-
tephroite (1)
-
-
staurolite (1)
-
-
-
sheet silicates
-
chlorite group
-
chlorite (1)
-
-
clay minerals
-
kaolinite (2)
-
montmorillonite (1)
-
smectite (3)
-
-
mica group
-
glauconite (2)
-
-
-
-
sulfides
-
chalcopyrite (1)
-
copper sulfides (1)
-
gersdorffite (1)
-
nickel sulfides (1)
-
pentlandite (1)
-
pyrite (1)
-
pyrrhotite (1)
-
-
-
Primary terms
-
absolute age (6)
-
Africa
-
Adrar des Iforas (1)
-
Central Africa
-
Angola
-
Cabinda Angola (1)
-
-
Central African Republic (3)
-
Congo (2)
-
Congo Democratic Republic (2)
-
Equatorial Guinea (1)
-
Gabon (4)
-
-
Congo Craton (1)
-
East Africa
-
Ethiopia (3)
-
Kenya (3)
-
Malawi (1)
-
Mozambique (3)
-
Sudan (1)
-
Tanzania (1)
-
Uganda (1)
-
-
Madagascar (2)
-
North Africa
-
Algeria
-
Ahaggar (1)
-
-
Atlas Mountains
-
Moroccan Atlas Mountains
-
Anti-Atlas (1)
-
-
-
Egypt (1)
-
Morocco
-
Moroccan Atlas Mountains
-
Anti-Atlas (1)
-
-
-
-
Sahara (1)
-
Senegal River (1)
-
Southern Africa
-
Lesotho (1)
-
Namibia
-
Walvis Bay Namibia (1)
-
-
South Africa
-
Witwatersrand (1)
-
-
Zimbabwe (1)
-
-
West Africa
-
Benin (5)
-
Burkina Faso (6)
-
Cameroon (4)
-
Chad (1)
-
Gambia (1)
-
Ghana (16)
-
Guinea (6)
-
Ivory Coast (67)
-
Liberia (6)
-
Mali (2)
-
Mauritania (4)
-
Niger (3)
-
Nigeria (4)
-
Nimba Mountains (1)
-
Senegal (4)
-
Sierra Leone (3)
-
Togo (4)
-
-
West African Craton (2)
-
West African Shield (2)
-
-
Asia
-
Central Asia
-
Kazakhstan
-
Aktyubinsk Kazakhstan
-
Zhamanshin Crater (1)
-
-
-
-
Far East
-
Indochina (1)
-
Indonesia (1)
-
Vietnam
-
Dalat Vietnam (1)
-
-
-
-
Atlantic Ocean
-
East Atlantic (1)
-
Equatorial Atlantic (3)
-
North Atlantic
-
Gulf of Guinea (6)
-
-
South Atlantic
-
Falkland Plateau (1)
-
-
-
Atlantic Ocean Islands
-
Ascension Island (1)
-
-
atmosphere (2)
-
Australasia
-
Australia (1)
-
New Zealand (1)
-
-
biogeography (1)
-
Canada
-
Western Canada
-
Athabasca Basin (1)
-
Saskatchewan (1)
-
-
-
carbon
-
organic carbon (2)
-
-
Caribbean region
-
West Indies
-
Antilles
-
Lesser Antilles
-
Martinique (1)
-
-
-
-
-
Cenozoic
-
Quaternary
-
Holocene (3)
-
Pleistocene (2)
-
-
Tertiary
-
Neogene
-
Miocene (1)
-
-
Paleogene
-
Eocene (2)
-
Oligocene (1)
-
Paleocene (1)
-
-
-
-
clay mineralogy (9)
-
climate change (2)
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continental slope (3)
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crust (5)
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crystal chemistry (1)
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crystal growth (1)
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crystal structure (2)
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data processing (1)
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deformation (5)
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diamond deposits (2)
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Earth (1)
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earthquakes (1)
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economic geology (4)
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Europe
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Central Europe (1)
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Western Europe
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France (1)
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Scandinavia
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Denmark (1)
-
-
-
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explosions (2)
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faults (12)
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folds (2)
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foliation (1)
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geochemistry (9)
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geochronology (3)
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geomorphology (1)
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geophysical methods (15)
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glacial geology (1)
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ground water (2)
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heat flow (1)
-
hydrogen
-
D/H (1)
-
-
hydrogeology (1)
-
hydrology (2)
-
igneous rocks
-
plutonic rocks
-
diabase (1)
-
gabbros (1)
-
granites
-
charnockite (2)
-
-
pegmatite (1)
-
ultramafics
-
pyroxenite
-
clinopyroxenite (1)
-
-
-
-
volcanic rocks
-
basalts
-
tholeiite (1)
-
-
glasses
-
volcanic glass (1)
-
-
pyroclastics
-
tuff (1)
-
-
-
-
inclusions
-
fluid inclusions (2)
-
-
Indian Ocean
-
Exmouth Plateau (1)
-
Mozambique Channel (1)
-
-
Indian Ocean Islands
-
Madagascar (2)
-
Mauritius (1)
-
-
intrusions (6)
-
Invertebrata
-
Arthropoda
-
Mandibulata
-
Crustacea
-
Malacostraca (1)
-
-
-
-
Cnidaria
-
Anthozoa (1)
-
-
Protista
-
Foraminifera
-
Rotaliina
-
Rotaliacea
-
Nummulitidae
-
Nummulites
-
Operculina (1)
-
-
-
-
-
-
-
-
isotopes
-
stable isotopes
-
D/H (1)
-
O-18/O-16 (1)
-
S-34/S-32 (1)
-
-
-
lava (1)
-
magmas (3)
-
mantle (1)
-
maps (1)
-
marine geology (2)
-
marine installations (1)
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Albian (1)
-
Aptian (1)
-
-
Upper Cretaceous
-
Cenomanian (1)
-
Coniacian (1)
-
Santonian (1)
-
Senonian (1)
-
Turonian (1)
-
-
-
Jurassic (1)
-
-
metal ores
-
aluminum ores (1)
-
copper ores (2)
-
gold ores (5)
-
iron ores (2)
-
manganese ores (3)
-
nickel ores (3)
-
niobium ores (1)
-
platinum ores (1)
-
tantalum ores (1)
-
-
metals
-
actinides
-
uranium (1)
-
-
alkali metals
-
rubidium (1)
-
-
alkaline earth metals
-
calcium (1)
-
magnesium (2)
-
strontium (1)
-
-
aluminum (1)
-
copper (1)
-
gold (1)
-
iron
-
ferric iron (2)
-
ferrous iron (2)
-
-
lead (1)
-
manganese (2)
-
nickel (1)
-
platinum group
-
platinum ores (1)
-
-
rare earths (1)
-
-
metamorphic rocks
-
amphibolites (1)
-
gneisses (2)
-
granulites (1)
-
impactites (2)
-
metaigneous rocks
-
metadiabase (1)
-
-
metasedimentary rocks (2)
-
metasomatic rocks
-
skarn (2)
-
-
metavolcanic rocks (1)
-
migmatites (1)
-
schists
-
greenstone (1)
-
-
-
metamorphism (6)
-
metasomatism (1)
-
meteorites (1)
-
mineral deposits, genesis (8)
-
mineral exploration (3)
-
mineralogy (2)
-
minerals (3)
-
Mohorovicic discontinuity (1)
-
nodules (1)
-
North America
-
Canadian Shield
-
Superior Province (1)
-
-
-
Ocean Drilling Program
-
Leg 159
-
ODP Site 959 (4)
-
ODP Site 960 (1)
-
ODP Site 961 (1)
-
ODP Site 962 (1)
-
-
-
ocean floors (3)
-
oceanography (2)
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orogeny (5)
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oxygen
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O-18/O-16 (1)
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paleoclimatology (2)
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paleogeography (1)
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paleomagnetism (1)
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paleontology (2)
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Paleozoic (1)
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paragenesis (3)
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petroleum
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natural gas (1)
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-
petrology (6)
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phase equilibria (1)
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placers (1)
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Plantae
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algae
-
nannofossils (1)
-
-
-
plate tectonics (8)
-
pollution (1)
-
Precambrian
-
Archean (5)
-
upper Precambrian
-
Proterozoic
-
Paleoproterozoic
-
Birimian (11)
-
-
-
-
-
remote sensing (2)
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sea-floor spreading (1)
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sea-level changes (1)
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sedimentary petrology (4)
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sedimentary rocks
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chemically precipitated rocks
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evaporites
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salt (1)
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ferricrete (1)
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weathering crust (1)
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clastic rocks
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black shale (1)
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red beds (1)
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sandstone (2)
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shale (2)
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sedimentary structures
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bedding plane irregularities
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grooves (1)
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secondary structures
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sedimentation (1)
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sediments
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clastic sediments
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colluvium (1)
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soils
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laterites (4)
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South America
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Brazil (2)
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Guiana Shield (2)
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stratigraphy (3)
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sulfur
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S-34/S-32 (1)
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tectonics
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salt tectonics (1)
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tektites (4)
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United States
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New Mexico
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Otero County New Mexico (1)
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Socorro County New Mexico (1)
-
-
North Carolina (1)
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Texas (1)
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Washington (1)
-
-
water resources (1)
-
weathering (8)
-
-
sedimentary rocks
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oolite (1)
-
sedimentary rocks
-
chemically precipitated rocks
-
evaporites
-
salt (1)
-
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ferricrete (1)
-
weathering crust (1)
-
-
clastic rocks
-
black shale (1)
-
red beds (1)
-
sandstone (2)
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sedimentary structures
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secondary structures
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sediments
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oolite (1)
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soils
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laterites (4)
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GeoRef Categories
Era and Period
Epoch and Age
Book Series
Date
Availability
Ivory Coast
Hydroacoustic Signals Recorded by CTBTO Network Suggest a Possible Submarine Landslide in Trou Sans Fond Canyon, Offshore Ivory Coast, March 2024 Available to Purchase
A tectonic model for the juxtaposition of granulite- and amphibolite-facies rocks in the Eburnean orogenic belt (Sassandra-Cavally domain, Côte d’Ivoire) Open Access
Multifrequency electromagnetic method for the hydrogeophysical characterization of hard-rock aquifers: the case of the upstream watershed of White Bandama (northern Ivory Coast) Open Access
Ni-Cu sulfide mineralization and PGM from the Samapleu mafic-ultramafic intrusion, Yacouba complex, western Ivory Coast Available to Purchase
Insights into the Early Evolution of the Côte d'Ivoire Margin (West Africa) Available to Purchase
Abstract A tectono-stratigraphic analysis of a broadband 3D seismic survey over the outer slope of Côte d'Ivoire margin, west Africa, revealed that Cenomanian and younger strata seal well-developed rift fault blocks up to 15 km across. Growth strata indicate that these were formed during rifting that culminated in seafloor spreading in the late Albian, challenging existing plate reconstructions for the opening of the equatorial Atlantic ocean. A previously unrecognized system of volcanic edifices linked at depth to a network of sill complexes has also been identified. These are aligned along a NE–SW trend, concordant with kilometre-wide ridges, interpreted as folds formed by steep, crustal faults with an oblique-slip component. These trends are similar to those of fracture zones in the region and indicate that the Côte d'Ivoire was a transform margin in the late Albian. These results highlight the potential of offshore Côte d'Ivoire for deep-water rift plays with large traps formed by extensional fault blocks together with prospective Albian reservoirs ponded in their hanging walls. In addition, the volcanoes and ridges generated seabed relief along the newly created transform margin, forming confined basins for potential deposition of Turonian and younger turbidites and the generation of stratigraphic traps.
Eburnean deformation pattern of Burkina Faso and the tectonic significance of shear zones in the West African craton Open Access
Typology of hard rock ground waters within the Lower Sassandra, a main catchment in humid tropical West Africa Available to Purchase
Abstract Randomness of fracture networks still makes channelized flow a challenge to track in hard-rock aquifers. While not underestimating geological and hydrological criteria that are also handled here through mapping exercises, this study raises an issue of water quality encountered in lifelong boreholes. Chemical classification checked against a recent conceptual model of bedrock aquifers gives birth to a new typology of groundwater in a complex granitic aquifer system located in the SW of Ivory Coast (West Africa). Major ion chemistry, borehole completion data, digital elevation model and satellite images are used to interpret the geochemical water facies as an expression of connexions between the saprolite and the saprock, or transient insulation. From major ions ratios, cumulate mineralization, carbonate equilibrium, stable isotopes, the maturation of ground waters and mixing between bedrock layers are described at seasonal and local scales. The results highlight some vertical feeding of the water table into the main saprock aquifer owing to shortcuts through the saprolite, along with the existence of dead-ends in the hydraulically active fracture network. Also, some influence of fault zones, either drain or barrier, is confirmed on the (Ca, Mg) bicarbonate water facies within the saprock.
REMOVAL OF PHOSPHATE BY IVORY COAST SHALE IN A HOMOGENEOUS REACTOR AND UNDER HYDRODYNAMIC CONDITIONS: INFLUENCE OF SOLUBLE SPECIES Available to Purchase
Tectonics-mineralisation relationships within weak continental lithospheres: a new structural framework for Precambrian cratons Open Access
Seismic reservoir characterization of a class-1 amplitude variation with offset turbiditic system located offshore Cote d’Ivoire, West Africa Available to Purchase
The Tongon Au Deposit, Northern Côte d’Ivoire: An Example of Paleoproterozoic Au Skarn Mineralization Available to Purchase
West Africa: The World’s Premier Paleoproterozoic Gold Province Available to Purchase
Petroleum systems asymmetry across the South Atlantic Equatorial Margins Available to Purchase
Abstract We describe an examination of two lines of evidence, tectono-structural evolution and hydrocarbon geochemistry, of asymmetric opening of the Atlantic Equatorial Margin. Our structural mapping used compilations of geophysical data and a review of both published literature and oil company public presentations. Geochemically, we accessed regional non-exclusive oil studies of the conjugate margins of Africa and South America, plus considerable published material. A group of non-exclusive oils was refined to 286, which clustered into five families, all represented along the NE Brazil margin but only one along the West African Transform (WAT) margin. Multiple lacustrine-sourced oils were seen around the South Atlantic, including NE Brazil, but a rich, oil-prone lacustrine source was not indicated offshore Ivory Coast and Ghana. Despite minor evidence of mixed source, possibly lacustrine stringers within an alluvial to marine setting, the predominant source is marine Cretaceous (Cenomanian–Turonian and possibly Albian). We find that opening asymmetry (a) biased the location of lacustrine (Early to mid-Cretaceous prerift to early synrift) source rocks to the NE Brazil margin and (b) locally narrowed the width of the optimal marine (Mid-Late Cretaceous postrift) WAT Margin source kitchens. Burial of the latter has aggravated the risk of late charge from light (condensate and gas) hydrocarbons.
Lower-crust ductility patterns associated with transform margins Available to Purchase
Abstract A three-dimensional (3D) thermal–kinematic modelling approach based on finite-element techniques is used to study lower-crustal viscosity at transform margins during the continent–ocean transform development stage and after the ridge has passed by. Nine modelling scenarios combining different equilibrium surface heat flows and lower-crustal rheologies are studied. Modelling results indicate that substantial parts of the lower crust at transform margins have the potential to flow at geologically appreciable strain rates, which can lead to uplift/subsidence, as well as lateral variations, in upper- and lower-crustal thicknesses and Moho depth. These low-viscosity zones (i.e. parts of the lower crust with effective viscosities of less than 10 18 Pa s) make up distinct ductility distributions that vary in space and time during margin evolution. Three basic ductility patterns and related thermal processes can be identified: reduced lower-crustal viscosities originating at the continental rift and the continent–ocean boundary (COB), respectively; reduced lower-crustal viscosities along the transform caused by the migrating ridge; and the background distribution of lower-crustal ductility resulting from the equilibrium temperature field. Superposition of all three ductility patterns and the complex interaction of the underlying perturbations of the temperature field result in distinct differences in the potential of lower-crustal flow both in space (parallel and perpendicular to the transform) and with time. Thus, modelling results provide templates for understanding lower-crustal flow at transform margins in general and await further studies comparing model predictions with actual field observations.
The Samapleu mafic-ultramafic intrusion and its Ni-Cu-PGE mineralization: an Eburnean (2.09 Ga) feeder dyke to the Yacouba layered complex (Man Archean craton, western Ivory Coast) Available to Purchase
North American microtektites are more oxidized than tektites Available to Purchase
THE RATE AND MECHANISM OF DEEP-SEA GLAUCONITE FORMATION AT THE IVORY COAST–GHANA MARGINAL RIDGE Available to Purchase
Evaluating Contributions to SK ( K ) S Splitting from Lower Mantle Anisotropy: A Case Study from Station DBIC, Côte D’Ivoire Available to Purchase
Iron reduction in silicate glass produced during the 1945 nuclear test at the Trinity site (Alamogordo, New Mexico, USA) Available to Purchase
We studied the oxidation state of Fe in silicate glasses produced during the first atomic bomb blast at the Trinity test site (New Mexico) by X-ray absorption–near edge spectroscopy (XANES). The sample consists of green glass resulting from melting of the quartz-bearing sand present at the test site; some relict unmelted sand is still fused to the bottom of the sample. Comparison of the pre-edge peak data with model compounds of known Fe oxidation state and coordination number shows that in the Trinity glass sample, Fe is in the divalent state and, on average, in a mixture of 4- and 5-fold coordination. XANES spectra collected at various heights of the sample, from the bottom of the sample up to the exposed surface, show no variation of the pre-edge peak and, thus, of the Fe oxidation state with the distance from the sand-glass interface. However, XANES analysis of a portion of the sand at the bottom of the sample shows Fe to be a mixture of Fe 2+ and Fe 3+ , with a Fe 3+ /(Fe 2+ + Fe 3+) ratio close to 0.5. This demonstrates that during the nuclear explosion, the ground rock was instantaneously reduced, transforming all the iron from mostly trivalent state to almost exclusively divalent. Pre-edge peak features (intensity and energy) are consistent with those of tektites from the Ivory Coast studied here and with literature data of tektites from all the other known strewn fields (Australasian, Central European, and North American). The reduction of Fe to divalent state during Trinity glass formation, the homogeneity of the Fe oxidation state within the glass, and the Fe structural role suggest that this glass represents a good analog of tektite glass.