Brief Description
– Granite-related deposits occur in collisional orogen, well inboard of fossil convergent plate margins and often spatially associated with tin-tungsten and intrusion-related gold provinces.
– The uranium ores take the form of vein-, stockwork- or episyenite-hosted deposits enclosed by, at the contact with or in the periphery of granitic intrusions, in particular highly differentiated leucogranites.
– Two subtypes, endogranitic and perigranitic, can be distinguished based on their spatial relationships with granitic intrusions and the surrounding country rocks.
– Endogranitic deposits (subtype 2.1) are typically monometallic (U) and largely confined to granite.
– Perigranitic deposits (subtype 2.2), on the other hand, may be mono- (U) or polymetallic (U ± Ag, As, Bi, Co, Ni) and are typically confined to the country rocks at the contact with and/or surrounding granitic intrusions.
Subtypes
– 2.1. Granite-related, endogranitic – 2.2. Granite-related, perigranitic Type Examples
– Subtype 2.1. La Crouzille district, France; Xiazhuang district, China – Subtype 2.2. Příbram district, Czech Republic; Niederschlema, Germany Principal Commodities
– U ± Ag, As, Bi, Co, Ni
Grades (%) and Tonnages (tU) – Average: 0.2030, 1280.8
– Median: 0.1600, 72.0 Number of Deposits – 667
Provinces
– Alto Alentejo, Aguila, Altai Belt, Amorican Massif, Andujar, Asele, Bange Jiali, Beiras, Burgas, Burro Mountains, Cabeza de Araya, Central Bohemian, Chandu, Coast Plutonic Complex, Copper Mountain, Cornwall, Criffel Granodiorite, East Balkan, Erzgebirge Karlovy Vary Massif, Fichtelgebirge, Finhaut Salvan Aiguilles Rouges Massif, Gogi Kanchankayi, Horni Slavkov, Hotagen Olden Window, Janja Massif, Jiuyishan Jinjiling, Kedougou Kenieba, Kentai Daur, Korolevo Chasovo, La Haba Don Benito, La Jara Sierra De Altamira, La Preciosa, Los Gigantes, Massif Central, Mirandela, North Qinling, Northern Grauwackenzone West Balkan, Northern Rocky Mountains, Nubian Shield, Qimen Tagh, Rila Mountains, Savoy Alps, Schwarzwald, Sonora, Southern Kalyma River, Taoshan Zhuguang Belt, Tingogasta, Villar de Peralonso, West Sredna Gora, Western Cameroon Domain, Westsudetic Silesian.
Tectonic Setting – Collisional orogens
Typical Geological Age Range – Palaeozoic to Mesozoic
Mineral Systems Model
SourceGround preparation – Orogenesis
– Emplacement of uraniferous (leuco-)granitoids
– Hornfelsing of country rocks in contact metamorphic aureoles
– Development or reactivation of graben structures facilitating infiltration of meteoric and/or basinal brines – Pervasive wallrock alteration prior to mineralisation
Energy
– High heat flow, extreme geothermal gradient and partial melting of mantle and/or crustal sources – Voluminous magmatism and emplacement of felsic to intermediate, peraluminous intrusions Fluids
– Magmatic-hydrothermal fluids
– Unknown, could be meteoric fluids, basinal brines, or metamorphic fluids Ligands
– Ca, Na, CO2
Reductants
– Reducing lithologies; sulphides; Fe2+ silicates; hydrocarbons; H2S Uranium
– Peraluminous U-enriched granitoids (in particular peraluminous two-mica leucogranites containing easily leachable uraninite); U-enriched high-K calc-alkaline granitoids; U-enriched basement rocks
Transport Fluid pathways
– Crustal-scale fault zones
44
– Anticlinal hinge zones
– Stratigraphic aquifers (overlying basin successions) Trap
Physical
– Transient breaching of physical barriers/seals, catastrophic rock failure and concomitant structurally controlled and highly focused fluid flow controlled by gradients in permeability and hydraulic head
– Gradients in permeability and hydraulic head are maximised at fault irregularities, fault tips and wings, fault intersections, fault damage zones characterised by high fracture density, competency contrasts, regional unconformities, apices of granitic cusps and ridges, strain shadows and contact aureoles around intrusive bodies, fold axes and fold axial cleavages, folds truncated by faults; lithological contacts or episyenites
Deposition
Phase separation
– Fluid unmixing due to depressurisation Fluid/wallrock interaction
– Chance in redox conditions due to interaction of oxidised fluids and reduced wall rocks Fluid mixing
– Chance in redox conditions due to interaction of oxidised fluids and reduced (H2S-bearing) brines Preservation
– Relative tectonic stability post-uranium mineralisation – Subsidence and burial of the uranium mineralised rocks
Key Reference Bibliography
DAHLKAMP, F. J., Uranium Deposits of the World: Asia. Springer, Berlin, Heidelberg, 492p (2009).
DAHLKAMP, F. J., Uranium Deposits of the World: Europe. Springer, Berlin, Heidelberg, 792p (2016).
DOLNÍČEK, Z., RENÉ, M., HERMANNOVÁ, S., PROCHASKA, W., Origin of the Okrouhlá Radouň episyenite-hosted uranium deposit, Bohemian Massif, Czech Republic: fluid inclusion and stable isotope constraints. Mineralium Deposita, 49(4), 409-425 (2014).
INTERNATIONAL ATOMIC ENERGY AGENCY, Geological Classification of Uranium Deposits and Description of Selected Examples. IAEA-TECDOC Series, 1842, 415p (2018).
RUZICKA, V., Vein uranium deposits. Ore Geology Reviews, 8(3-4), 247-276 (1993).
45
FIG. 2a. World distribution of selected Granite-Related uranium deposits from the UDEPO database.FIG. 2b. Grade and tonnage scatterplot highlighting Granite-Related uranium deposits from the UDEPO database.
46
FIG. 2c. Grade Cumulative Probability Plot for Granite-Related uranium deposits from the UDEPO database.
FIG. 2d. Tonnage Cumulative Probability Plot for Granite-Related uranium deposits from the UDEPO database.
47 SUBTYPE 2.1. Granite-Related, Endogranitic
Brief Description
– Granite-related deposits occur in collisional orogen, well inboard of fossil convergent plate margins and often spatially associated with tin-tungsten and intrusion-related gold provinces.
– The uranium ores take the form of vein-, stockwork- or episyenite-hosted deposits enclosed by, at the contact with or in the periphery of granitic intrusions, in particular highly differentiated leucogranites.
– Two subtypes, endogranitic and perigranitic, can be distinguished based on their spatial relationships with granitic intrusions and the surrounding country rocks.
– Endogranitic deposits (subtype 2.1) are typically monometallic (U) and largely confined to granite.
Type Examples
– La Crouzille, Bernardan and La Marche districts, France; Xiazhuang district, China; Gornoye, Russian Federation Genetically Associated Deposit Types
– Subtype 1.1. Intrusive, anatectic (pegmatite-alaskite) – Subtype 2.2. Granite-related, perigranitic
– Subtype 5.1.1. Metasomatite, Sodium (Na)-metasomatite, granite derived – Subtype 5.3. Metasomatite, skarn
Principal Commodities – U
Grades (%) and Tonnages (tU) – Average: 0.2210, 595.5
– Median: 0.1650, 50 Number of Deposits – 444
Provinces (undifferentiated from Granite-related Type)
– Alto Alentejo, Aguila, Altai Belt, Amorican Massif, Andujar, Asele, Bange Jiali, Beiras, Burgas, Burro Mountains, Cabeza de Araya, Central Bohemian, Chandu, Coast Plutonic Complex, Copper Mountain, Cornwall, Criffel Granodiorite, East Balkan, Erzgebirge Karlovy Vary Massif, Fichtelgebirge, Finhaut Salvan Aiguilles Rouges Massif, Gogi Kanchankayi, Horni Slavkov, Hotagen Olden Window, Janja Massif, Jiuyishan Jinjiling, Kedougou Kenieba, Kentai Daur, Korolevo Chasovo, La Haba Don Benito, La Jara Sierra De Altamira, La Preciosa, Los Gigantes, Massif Central, Mirandela, North Qinling, Northern Grauwackenzone West Balkan, Northern Rocky Mountains, Nubian Shield, Qimen Tagh, Rila Mountains, Savoy Alps, Schwarzwald, Sonora, Southern Kalyma River, Taoshan Zhuguang Belt, Tingogasta, Villar de Peralonso, West Bohemian, West Kunlanshan, West Sredna Gora
Tectonic Setting – Collisional orogens
Typical Geological Age Range – Palaeozoic to Mesozoic
Mineral Systems Model
SourceGround preparation – Orogenesis
– Emplacement of uraniferous (leuco-)granitoids
– Hornfelsing of country rocks in contact metamorphic aureoles
– Development or reactivation of graben structures facilitating infiltration of meteoric and/or basinal brines – Pervasive wallrock alteration prior to mineralisation
Energy
– High heat flow, extreme geothermal gradient and partial melting of mantle and/or crustal sources – Voluminous magmatism and emplacement of felsic to intermediate, peraluminous intrusions Fluids
– Magmatic-hydrothermal fluids
– (?)Meteoric fluids, (?)basinal brines, (?)metamorphic fluids Ligands
– Ca, Na, CO2
Reductants
– Reducing lithologies; sulphides; Fe2+ silicates; hydrocarbons; H2S Uranium
– Peraluminous U-enriched granitoids (in particular peraluminous two-mica leucogranites containing easily leachable uraninite); U-enriched high-K calc-alkaline granitoids; U-enriched basement rocks
Transport Fluid pathways
– Crustal-scale fault zones
48
– Anticlinal hinge zones
– Stratigraphic aquifers (overlying basin successions) Trap
Physical
– Transient breaching of physical barriers/seals, catastrophic rock failure and concomitant structurally controlled and highly focused fluid flow controlled by gradients in permeability and hydraulic head
– Gradients in permeability and hydraulic head are maximised at fault irregularities, fault tips and wings, fault intersections, fault damage zones characterised by high fracture density, competency contrasts, regional unconformities, apices of granitic cusps and ridges, strain shadows and contact aureoles around intrusive bodies, fold axes and fold axial cleavages, folds truncated by faults; lithological contacts or episyenites
Deposition
Phase separation
– Fluid unmixing due to depressurisation Fluid/wallrock interaction
– Chance in redox conditions due to interaction of oxidised fluids and reduced wall rocks Fluid mixing
– Chance in redox conditions due to interaction of oxidised fluids and reduced (H2S-bearing) brines Preservation
– Relative tectonic stability post-uranium mineralisation – Subsidence and burial of the uranium mineralised rocks
Key Reference Bibliography
DAHLKAMP, F. J., Uranium Deposits of the World: Asia. Springer, Berlin, Heidelberg, 492p (2009).
DAHLKAMP, F. J., Uranium Deposits of the World: Europe. Springer, Berlin, Heidelberg, 792p (2016).
DOLNÍČEK, Z., RENÉ, M., HERMANNOVÁ, S., PROCHASKA, W., Origin of the Okrouhlá Radouň episyenite-hosted uranium deposit, Bohemian Massif, Czech Republic: fluid inclusion and stable isotope constraints. Mineralium Deposita, 49(4), 409-425 (2014).
INTERNATIONAL ATOMIC ENERGY AGENCY, Geological Classification of Uranium Deposits and Description of Selected Examples. IAEA-TECDOC Series, 1842, 415p (2018).
RUZICKA, V., Vein uranium deposits. Ore Geology Reviews, 8(3-4), 247-276 (1993).
49
FIG. 2.1a. World distribution of selected Granite-Related Endogranitic uranium deposits from the UDEPO database.FIG. 2.1b. Grade and tonnage scatterplot highlighting Granite-Related Endogranitic uranium deposits from the UDEPO database.
50
FIG. 2.1c. Grade Cumulative Probability Plot for Granite-Related Endogranitic uranium deposits from the UDEPO database.
FIG. 2.1d. Tonnage Cumulative Probability Plot for Granite-Related Endogranitic uranium deposits from the UDEPO database.
51 SUBTYPE 2.2. Granite-Related, Perigranitic
Brief Description
– Granite-related deposits occur in collisional orogen, well inboard of fossil convergent plate margins and often spatially associated with tin-tungsten and intrusion-related gold provinces.
– The uranium ores take the form of vein-, stockwork- or episyenite-hosted deposits enclosed by, at the contact with or in the periphery of granitic intrusions, in particular highly differentiated leucogranites.
– Two subtypes, endogranitic and perigranitic, can be distinguished based on their spatial relationships with granitic intrusions and the surrounding country rocks.
– Perigranitic deposits (subtype 2.2), on the other hand, may be mono- (U) or polymetallic (U ± Ag, As, Bi, Co, Ni) and are typically confined to the country rocks at the contact with and/or surrounding granitic intrusions.
Type Examples
– Příbram district, Czech Republic; Niederschlema-Alberoda, Germany; Alto Alentejo district, Portugal Genetically Associated Deposit Types
– Subtype 2.2. Granite-related, endogranitic Principal Commodities
– U ± Ag, As, Bi, Co, Ni
Grades (%) and Tonnages (tU) – Average: 0.1481, 2304.8
– Median: 0.1020, 301.5 Number of Deposits – 222
Provinces (undifferentiated from Granite-related Type)
– Alto Alentejo, Aguila, Altai Belt, Amorican Massif, Andujar, Asele, Bange Jiali, Beiras, Burgas, Burro Mountains, Cabeza de Araya, Central Bohemian, Chandu, Coast Plutonic Complex, Copper Mountain, Cornwall, Criffel Granodiorite, East Balkan, Erzgebirge Karlovy Vary Massif, Fichtelgebirge, Finhaut Salvan Aiguilles Rouges Massif, Gogi Kanchankayi, Horni Slavkov, Hotagen Olden Window, Janja Massif, Jiuyishan Jinjiling, Kedougou Kenieba, Kentai Daur, Korolevo Chasovo, La Haba Don Benito, La Jara Sierra De Altamira, La Preciosa, Los Gigantes, Massif Central, Mirandela, North Qinling, Northern Grauwackenzone West Balkan, Northern Rocky Mountains, Nubian Shield, Qimen Tagh, Rila Mountains, Savoy Alps, Schwarzwald, Sonora, Southern Kalyma River, Taoshan Zhuguang Belt, Tingogasta, Villar de Peralonso, West Bohemian, West Kunlanshan, West Sredna Gora, Western Cameroon Domain, Westsudetic Silesian.
Tectonic Setting – Collisional orogens
Typical Geological Age Range – Palaeozoic to Mesozoic
Mineral Systems Model
SourceGround preparation – Orogenesis
– Emplacement of uraniferous (leuco-)granitoids
– Hornfelsing of country rocks in contact metamorphic aureoles
– Development or reactivation of graben structures facilitating infiltration of meteoric and/or basinal brines – Pervasive wallrock alteration prior to mineralisation
Energy
– High heat flow, extreme geothermal gradient and partial melting of mantle and/or crustal sources – Voluminous magmatism and emplacement of felsic to intermediate, peraluminous intrusions Fluids
– Magmatic-hydrothermal fluids
– (?)Meteoric fluids, (?)basinal brines, (?)metamorphic fluids Ligands
– Ca, Na, CO2
Reductants
– Reducing lithologies; sulphides; Fe2+ silicates; hydrocarbons; H2S Uranium
– Peraluminous U-enriched granitoids (in particular peraluminous two-mica leucogranites containing easily leachable uraninite); U-enriched high-K calc-alkaline granitoids; U-enriched basement rocks
Transport Fluid pathways
– Crustal-scale fault zones – Anticlinal hinge zones
– Stratigraphic aquifers (overlying basin successions)
52
TrapPhysical
– Transient breaching of physical barriers/seals, catastrophic rock failure and concomitant structurally controlled and highly focused fluid flow controlled by gradients in permeability and hydraulic head
– Gradients in permeability and hydraulic head are maximised at fault irregularities, fault tips and wings, fault intersections, fault damage zones characterised by high fracture density, competency contrasts, regional unconformities, apices of granitic cusps and ridges, strain shadows and contact aureoles around intrusive bodies, fold axes and fold axial cleavages, folds truncated by faults; lithological contacts or episyenites
Deposition
Phase separation
– Fluid unmixing due to depressurisation Fluid/wallrock interaction
– Chance in redox conditions due to interaction of oxidised fluids and reduced wall rocks Fluid mixing
– Chance in redox conditions due to interaction of oxidised fluids and reduced (H2S-bearing) brines Preservation
– Relative tectonic stability post-uranium mineralisation – Subsidence and burial of the uranium mineralised rocks
Key Reference Bibliography
DAHLKAMP, F. J., Uranium Deposits of the World: Asia. Springer, Berlin, Heidelberg, 492p (2009).
DAHLKAMP, F. J., Uranium Deposits of the World: Europe. Springer, Berlin, Heidelberg, 792p (2016).
DOLNÍČEK, Z., RENÉ, M., HERMANNOVÁ, S., PROCHASKA, W., Origin of the Okrouhlá Radouň episyenite-hosted uranium deposit, Bohemian Massif, Czech Republic: fluid inclusion and stable isotope constraints. Mineralium Deposita, 49(4), 409-425 (2014).
INTERNATIONAL ATOMIC ENERGY AGENCY, Geological Classification of Uranium Deposits and Description of Selected Examples. IAEA-TECDOC Series, 1842, 415p (2018).
RUZICKA, V., Vein uranium deposits. Ore Geology Reviews, 8(3-4), 247-276 (1993).
53
FIG. 2.2a. World distribution of selected Granite-Related Perigranitic uranium deposits from the UDEPO database.FIG. 2.2b. Grade and tonnage scatterplot highlighting Granite-Related Perigranitic uranium deposits from the UDEPO database.
54
FIG. 2.2c. Grade Cumulative Probability Plot for Granite-Related Perigranitic uranium deposits from the UDEPO database.
FIG. 2.2d. Tonnage Cumulative Probability Plot for Granite-Related Perigranitic uranium deposits from the UDEPO database.