Fort Munro Formation represents the products of the Upper Cretaceous (Maastrichtian) in the middle and lower Indus basins. The formation is exposed in the Rakhi Nala (Sulaiman Range), Bara Nala (Lakhi Range) and Naka ...Fort Munro Formation represents the products of the Upper Cretaceous (Maastrichtian) in the middle and lower Indus basins. The formation is exposed in the Rakhi Nala (Sulaiman Range), Bara Nala (Lakhi Range) and Naka Pabni (Southern Pab Range) areas. Major and trace elemental geochemistry and petrographic studies of the formation have been carried out to understand the facies trends in the middle and lower Indus basins. A high amount of acid-insoluble fraction, Ca/Mg and Mg vs. Ca/Sr ratio reveal that the formation was deposited in a shallow marine regressive environment. High amounts of clastic reflect abundant influx of terrigenous materials from the east (Indian craton) and west (Bibai volcanic). High Sr content indicates that aragonite was the precursor mineral, which was transformed into stable low-Mg calcite during diagenesis. Enrichment of Cu and Zn contents in the samples of the formation implies the influence of volcanic activity and that they were incorporated into the calcite lattice in the late phase.展开更多
China is in severe shortage of potash reserves,and the best way for breakthrough is to make potash exploration in marine salt basins.Erdos basin is so far the only Ordovician potash basin in the world.The Erdos basin ...China is in severe shortage of potash reserves,and the best way for breakthrough is to make potash exploration in marine salt basins.Erdos basin is so far the only Ordovician potash basin in the world.The Erdos basin is located west展开更多
This study investigates the facies development and sedimentology of the Late Permian Chhidru Formation,a mixed carbonate-siliciclastic unit exposed in the Western Salt Range,Potwar Basin,Pakistan.The formation is subd...This study investigates the facies development and sedimentology of the Late Permian Chhidru Formation,a mixed carbonate-siliciclastic unit exposed in the Western Salt Range,Potwar Basin,Pakistan.The formation is subdivided into four lithological units reflecting lateral variability,with thicknesses and lithologies ranging from fossiliferous sandy limestone to interbedded limestone and sandstone.These successions record a depositional shift from a carbonate platform to mixed carbonate-clastic,and ultimately,clastic-dominated environments.Lithostratigraphy suggests deposition on the underlying Wargal Limestone carbonates during a Late Permian sea-level fall on the northwest Indian margin of Gondwana.Similar Permian successions with identical lithological characteristics are documented in the Persian Gulf(Dalan Formation),Arabian Platform(Khuff Formation),and Iran(Nesen and Hambust formations).Petrographic analysis reveals deposition in the distal middle to proximal inner shelf settings of a carbonate-siliciclastic mixed,unrimmed platform.Based on identified foraminiferal assemblages,the Chhidru Formation's age is estimated to range from the late Wuchiapingian to Changhsingian stages of the Lopingian epoch.展开更多
Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar Craton including the oldest(~3.3 Ga)Sargur Group of western Dharwar Craton.The present study deals with the petro-graphic...Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar Craton including the oldest(~3.3 Ga)Sargur Group of western Dharwar Craton.The present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation history.Their major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and rutile.The geochemical com-positions are characterized by high SiO_(2),Al_(2)O_(3),low MgO,CaO,strongly enriched Cr(1326–6899 ppm),Ba(1165–3653 ppm),Sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(UCC).The UCC normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/Sm)UCC=0.33–0.95]compared to heavy REE[(Gd/Yb)_(UCC)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered barites.The overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin environ-ment.The comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by Cr-richfluids released during high-grade metamorphism of associated ultramafic rocks.The Sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of Cr-richfluids and the formation of fuchsite quartzite during or after the orogeny.Thesefindings sug-gest a pre-existing stable crust prior to the Sargur Group and the link between orogenic events and various mineral deposits in the Dharwar Craton.展开更多
China is the third largest country in the world, with a land area of about 9.6 million km2. It is endowed with abundant mineral resources, and the metal mining activity can be traced back to ca. 8000 years ago. Howeve...China is the third largest country in the world, with a land area of about 9.6 million km2. It is endowed with abundant mineral resources, and the metal mining activity can be traced back to ca. 8000 years ago. However, due to language barrier, little has been known about the geology and tectonics to the outside world until 1980s. In the last three decades, a great deal of knowledge has been gained, enhanced by a vigorous cooperation between Chinese and Western geologists. Research papers about geological, geochemical, and geochronological features of mineral deposits of China are widely published and cited in international journals. A comprehen- sive and comprehensible English literature that summarises the features of mineral deposits in China, however, is still lacking.展开更多
In accordance with the terms global minerogenic series, regional metallogenic series and ore depositsystem which are put forward here, metallogenic environments at different levels are discussed for theporphyry copper...In accordance with the terms global minerogenic series, regional metallogenic series and ore depositsystem which are put forward here, metallogenic environments at different levels are discussed for theporphyry copper deposit series in China. It is considered that the porphyry copper deposits in China arecontrolled not only by the boundaries of convergent plates but, more importantly, by the boundaries ofintraplate divergent mobile belts and those between continental blocks. Besides, the emplacement ofhypabyssal and supper-hypabyssal calc-alkaline magmas and the temporal-spatial distribution of China'sporphyry copper deposits are governed by the superimposition of fracture systems of the pre-Alpine base-ments. Meso-Cenozoic cover and continental-margin new-born crust. Such a superimposition has also re-sulted in the polycyclicity of the mineralization.展开更多
The Phlaythong large iron deposit in Shampasak of southern Laos,is located in the Kon Tum microblock （Fig.1A）,central-southern part of the Indo-China block,and the geographic coordinate of the central mining area is...The Phlaythong large iron deposit in Shampasak of southern Laos,is located in the Kon Tum microblock （Fig.1A）,central-southern part of the Indo-China block,and the geographic coordinate of the central mining area is 14°43′04″ N and 106°07′02″ E.展开更多
The North Altyn has underwent a complex tectonic history in the Early Paleozoic and formed a number of orogenic gold deposits controlled by ductile to brittle shear zones adjacent to the southern side of the Northern ...The North Altyn has underwent a complex tectonic history in the Early Paleozoic and formed a number of orogenic gold deposits controlled by ductile to brittle shear zones adjacent to the southern side of the Northern Altyn Tagh fault e.g. the Dapinggou, Beiketan and Xiangyun. The Dapinggou gold deposit, a typical orogenic gold deposit in North Altyn, is predominantly hosted in the Precambrian carbonate and Cambrian volcano- sedimentary rocks which were strongly deformed and were subjected to low-grade metamorphism. The ore bodies occurred in K-feldspar quartz veins and hydrothermally altered mylonite within the ductile shear belt. Hydrothermal alteration including silicification, pyritization.展开更多
The study reconstructs the Upper Devonian Domanik sedimentation conditions using geochemical studies.Domanik sediments,the subject of study,are being developed in Russia's Volga-Ural petroleum province.Core sample...The study reconstructs the Upper Devonian Domanik sedimentation conditions using geochemical studies.Domanik sediments,the subject of study,are being developed in Russia's Volga-Ural petroleum province.Core samples have been collected from the South Tatar arch and the Birskaya saddle,totaling four wells.Macroscopic description,optical microscopic petrographic examination,X-ray analysis,X-ray fluorescence analysis,inductively coupled plasma mass spectrometry(ICP-MS),simultaneous thermal analyses,scanning electronic microscopy(SEM),Rock-Eval pyrolytic studies,and correlation analysis were among the methods used in the study.Carbonate rocks,carbonate-siliceous rocks enriched with organic matter,and carbonate breccias are the main identified lithotypes.The predominant rock-forming mineral in carbonate-siliceous rocks enriched with organic matter is quartz(chalcedony)of authigenic genesis.The lack of co rrelation between organic matter concentration and quartz,as well as the results of simultaneous thermal studies and SEM,suggest that quartz is present in both biogenic and chemogenic forms.The proxies Cd/Mo and Co x Mn were used for proving variable hydrodynamic conditions in the Domanik sediments sea:sediments were deposited under both stationary and seasonal upwelling conditions.The major bioproductivity of the Domanik sea was also influenced by hydrothermal activity.The proxy(Fe+Mn)/Ti data and the results of the rock genesis evaluation using the Zn-Ni-Co triangle diagram confirm this.The presence of hydrothermal fluids not only improved primary production in the paleobasin,but it additionally provided silica,as evidenced by the strong relationship between silica and exhalation components in carbonate-siliceous rocks.Volcanic activity had a slight impact on Domanik sediment genesis.Anoxia and euxinia in the Domanik sea were indicated by proxy U/Th-TOC and V/CrTOC data,as well as behavior of U-EF and Mo-EF on the covariation plot,which influenced organic matter burial in the sediments.Simultaneously,the terrigenous intake was limited.Carbonate breccias,which are common in the Domanik sediments section,developed as a result of the gravitational transfer of carbonate fragments into the carbonate-siliceous material,which might be driven by earthquakes.展开更多
Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical str...Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical structure of the exploration and mining industry makes this situation difficult to redress. Economic geologists can do little to influence the required changes to the overall structure and philosophy of an industry driven by business rather than geological principles, However, it should be possible to follow the lead of the oil industry and improve the success rate of greenfield exploration, necessary for the next group of lower-exploration-spend significant mineral deposit discoveries. Here we promote the concept that mineral explorers need to carefully consider the scale at which their exploration targets are viewed. It is necessary to carefully assess the potential of drill targets in terms of terrane to province to district scale, rather than deposit scale, where most current economic geology research and conceptual thinking is concentrated. If orogenic, IRGD, Carlin-style and IOCG gold-rich systems are viewed at the deposit scale, they appear quite different in terms of conventionally adop- ted research parameters. However, recent models for these deposit styles show increasingly similar source-region parameters when viewed at the lithosphere scale, suggesting common tectonic settings. It is only by assessing individual targets in their tectonic context that they can be more reliably ranked in terms of potential to provide a significant drill discovery. Targets adjacent to craton margins, other lithosphere boundaries, and suture zones are clearly favoured for all of these gold deposit styles, and such exploration could lead to incidental discovery of major deposits of other metals sited along the same tectonic boundaries.展开更多
文摘Fort Munro Formation represents the products of the Upper Cretaceous (Maastrichtian) in the middle and lower Indus basins. The formation is exposed in the Rakhi Nala (Sulaiman Range), Bara Nala (Lakhi Range) and Naka Pabni (Southern Pab Range) areas. Major and trace elemental geochemistry and petrographic studies of the formation have been carried out to understand the facies trends in the middle and lower Indus basins. A high amount of acid-insoluble fraction, Ca/Mg and Mg vs. Ca/Sr ratio reveal that the formation was deposited in a shallow marine regressive environment. High amounts of clastic reflect abundant influx of terrigenous materials from the east (Indian craton) and west (Bibai volcanic). High Sr content indicates that aragonite was the precursor mineral, which was transformed into stable low-Mg calcite during diagenesis. Enrichment of Cu and Zn contents in the samples of the formation implies the influence of volcanic activity and that they were incorporated into the calcite lattice in the late phase.
基金funded by National Program on Key Basic Research Project of China-973 Program"Potash formation mechanism,conditionslate evolution in Ordovician ancient epicontinental sea basin,Erdos"(No.2011CB403001)China Geological survey work Program–"Potash resources investigation and evaluation in Northern Shaanxi Ordovician Salt Basin"(No.1212011085516)
文摘China is in severe shortage of potash reserves,and the best way for breakthrough is to make potash exploration in marine salt basins.Erdos basin is so far the only Ordovician potash basin in the world.The Erdos basin is located west
基金Dr.Stergios D.Zarkogiannis would like to acknowledge UK Research and Innovation Grant(SODIOM)EP/Y004221/1 in supporting the research reported here.
文摘This study investigates the facies development and sedimentology of the Late Permian Chhidru Formation,a mixed carbonate-siliciclastic unit exposed in the Western Salt Range,Potwar Basin,Pakistan.The formation is subdivided into four lithological units reflecting lateral variability,with thicknesses and lithologies ranging from fossiliferous sandy limestone to interbedded limestone and sandstone.These successions record a depositional shift from a carbonate platform to mixed carbonate-clastic,and ultimately,clastic-dominated environments.Lithostratigraphy suggests deposition on the underlying Wargal Limestone carbonates during a Late Permian sea-level fall on the northwest Indian margin of Gondwana.Similar Permian successions with identical lithological characteristics are documented in the Persian Gulf(Dalan Formation),Arabian Platform(Khuff Formation),and Iran(Nesen and Hambust formations).Petrographic analysis reveals deposition in the distal middle to proximal inner shelf settings of a carbonate-siliciclastic mixed,unrimmed platform.Based on identified foraminiferal assemblages,the Chhidru Formation's age is estimated to range from the late Wuchiapingian to Changhsingian stages of the Lopingian epoch.
基金funds MLP 6406-28(MRM)of CSIR-NGRIGH acknowledges DSTINSPIRE for PhD Fellowship(No.DST/INSPIRE/03/2021/001295)+1 种基金CM acknowledges the CSIR Emeritus Project funds。
文摘Meso-Neoarchean fuchsite quartzites are present in different stratigraphic positions of Dharwar Craton including the oldest(~3.3 Ga)Sargur Group of western Dharwar Craton.The present study deals with the petro-graphic and geochemical characteristics of the fuchsite quartzites from the Ghattihosahalli belt to evaluate their genesis,depositional setting and the enigma involved in the ancient sedimentation history.Their major mineral assemblages include quartz,fuchsite,and feldspars along with accessory kyanite and rutile.The geochemical com-positions are characterized by high SiO_(2),Al_(2)O_(3),low MgO,CaO,strongly enriched Cr(1326–6899 ppm),Ba(1165–3653 ppm),Sr(46–210 ppm),V(107–868 ppm)and Zn(11–158 ppm)contents compared to the upper continental crust(UCC).The UCC normalized rare earth element(REE)patterns are characterized by depleted light REE[(La/Sm)UCC=0.33–0.95]compared to heavy REE[(Gd/Yb)_(UCC)=0.42–1.65]with conspicuous positive Eu-anomalies(Eu/Eu^(*)=1.35–18.27)characteristic of hydrothermal solutions evidenced through the interlayered barites.The overall major and trace element systematics reflect a combined mafic-felsic provenance and suggest their deposition at a passive continental margin environ-ment.The comprehensivefield,petrographic,and geo-chemical studies indicate that these quartzites are infiltrated by Cr-richfluids released during high-grade metamorphism of associated ultramafic rocks.The Sargur and the subse-quent Dharwar orogeny amalgamated diverse lithounits from different tectonic settings,possibly leading to the release of Cr-richfluids and the formation of fuchsite quartzite during or after the orogeny.Thesefindings sug-gest a pre-existing stable crust prior to the Sargur Group and the link between orogenic events and various mineral deposits in the Dharwar Craton.
文摘China is the third largest country in the world, with a land area of about 9.6 million km2. It is endowed with abundant mineral resources, and the metal mining activity can be traced back to ca. 8000 years ago. However, due to language barrier, little has been known about the geology and tectonics to the outside world until 1980s. In the last three decades, a great deal of knowledge has been gained, enhanced by a vigorous cooperation between Chinese and Western geologists. Research papers about geological, geochemical, and geochronological features of mineral deposits of China are widely published and cited in international journals. A comprehen- sive and comprehensible English literature that summarises the features of mineral deposits in China, however, is still lacking.
文摘In accordance with the terms global minerogenic series, regional metallogenic series and ore depositsystem which are put forward here, metallogenic environments at different levels are discussed for theporphyry copper deposit series in China. It is considered that the porphyry copper deposits in China arecontrolled not only by the boundaries of convergent plates but, more importantly, by the boundaries ofintraplate divergent mobile belts and those between continental blocks. Besides, the emplacement ofhypabyssal and supper-hypabyssal calc-alkaline magmas and the temporal-spatial distribution of China'sporphyry copper deposits are governed by the superimposition of fracture systems of the pre-Alpine base-ments. Meso-Cenozoic cover and continental-margin new-born crust. Such a superimposition has also re-sulted in the polycyclicity of the mineralization.
基金financially supported by the Special fund for Foreign Mineral Resources Risk Exploration (Grant No.Sichuan Financial Investment (2010)331)China Geological Survey (Grant No.12120114012501)
文摘The Phlaythong large iron deposit in Shampasak of southern Laos,is located in the Kon Tum microblock （Fig.1A）,central-southern part of the Indo-China block,and the geographic coordinate of the central mining area is 14°43′04″ N and 106°07′02″ E.
文摘The North Altyn has underwent a complex tectonic history in the Early Paleozoic and formed a number of orogenic gold deposits controlled by ductile to brittle shear zones adjacent to the southern side of the Northern Altyn Tagh fault e.g. the Dapinggou, Beiketan and Xiangyun. The Dapinggou gold deposit, a typical orogenic gold deposit in North Altyn, is predominantly hosted in the Precambrian carbonate and Cambrian volcano- sedimentary rocks which were strongly deformed and were subjected to low-grade metamorphism. The ore bodies occurred in K-feldspar quartz veins and hydrothermally altered mylonite within the ductile shear belt. Hydrothermal alteration including silicification, pyritization.
基金funded by the subsidy allocated to Kazan Federal University for the state assignment in the sphere of scientific activities,project No.FZSM-2023-0014。
文摘The study reconstructs the Upper Devonian Domanik sedimentation conditions using geochemical studies.Domanik sediments,the subject of study,are being developed in Russia's Volga-Ural petroleum province.Core samples have been collected from the South Tatar arch and the Birskaya saddle,totaling four wells.Macroscopic description,optical microscopic petrographic examination,X-ray analysis,X-ray fluorescence analysis,inductively coupled plasma mass spectrometry(ICP-MS),simultaneous thermal analyses,scanning electronic microscopy(SEM),Rock-Eval pyrolytic studies,and correlation analysis were among the methods used in the study.Carbonate rocks,carbonate-siliceous rocks enriched with organic matter,and carbonate breccias are the main identified lithotypes.The predominant rock-forming mineral in carbonate-siliceous rocks enriched with organic matter is quartz(chalcedony)of authigenic genesis.The lack of co rrelation between organic matter concentration and quartz,as well as the results of simultaneous thermal studies and SEM,suggest that quartz is present in both biogenic and chemogenic forms.The proxies Cd/Mo and Co x Mn were used for proving variable hydrodynamic conditions in the Domanik sediments sea:sediments were deposited under both stationary and seasonal upwelling conditions.The major bioproductivity of the Domanik sea was also influenced by hydrothermal activity.The proxy(Fe+Mn)/Ti data and the results of the rock genesis evaluation using the Zn-Ni-Co triangle diagram confirm this.The presence of hydrothermal fluids not only improved primary production in the paleobasin,but it additionally provided silica,as evidenced by the strong relationship between silica and exhalation components in carbonate-siliceous rocks.Volcanic activity had a slight impact on Domanik sediment genesis.Anoxia and euxinia in the Domanik sea were indicated by proxy U/Th-TOC and V/CrTOC data,as well as behavior of U-EF and Mo-EF on the covariation plot,which influenced organic matter burial in the sediments.Simultaneously,the terrigenous intake was limited.Carbonate breccias,which are common in the Domanik sediments section,developed as a result of the gravitational transfer of carbonate fragments into the carbonate-siliceous material,which might be driven by earthquakes.
文摘Discovery rates for all metals, including gold, are declining, the cost per significant discovery is increasing sharply, and the economic situation of the industry is one of low base rate. The current hierarchical structure of the exploration and mining industry makes this situation difficult to redress. Economic geologists can do little to influence the required changes to the overall structure and philosophy of an industry driven by business rather than geological principles, However, it should be possible to follow the lead of the oil industry and improve the success rate of greenfield exploration, necessary for the next group of lower-exploration-spend significant mineral deposit discoveries. Here we promote the concept that mineral explorers need to carefully consider the scale at which their exploration targets are viewed. It is necessary to carefully assess the potential of drill targets in terms of terrane to province to district scale, rather than deposit scale, where most current economic geology research and conceptual thinking is concentrated. If orogenic, IRGD, Carlin-style and IOCG gold-rich systems are viewed at the deposit scale, they appear quite different in terms of conventionally adop- ted research parameters. However, recent models for these deposit styles show increasingly similar source-region parameters when viewed at the lithosphere scale, suggesting common tectonic settings. It is only by assessing individual targets in their tectonic context that they can be more reliably ranked in terms of potential to provide a significant drill discovery. Targets adjacent to craton margins, other lithosphere boundaries, and suture zones are clearly favoured for all of these gold deposit styles, and such exploration could lead to incidental discovery of major deposits of other metals sited along the same tectonic boundaries.
