A growing number of oil and gas reservoirs have been discovered in granite and metamorphic crystallized rock areas. Statistics show that, about 157 oil and gas fields were found in crystallized bedrocks, with oil rese...A growing number of oil and gas reservoirs have been discovered in granite and metamorphic crystallized rock areas. Statistics show that, about 157 oil and gas fields were found in crystallized bedrocks, with oil reserves of 5048x 10^8 t, and gas reserves of 2681x10^8m3. Among the discovered industrial oil and gas fields hosted in crystallized rocks, most occurred in granite rocks, occupying 40% in quantity and 75% in reserves, followed by those hosted in mafic and ultra-mafic rocks （about 3%）, and then tbllowed by those in volcanic rocks and metamorphic rocks.展开更多
Multi-constraints are used in this paper to discuss the ΣCO_2 source in oreforming hydrothermal solution of granite-type uranium deposit in South China. The studies show that highly acidic and uraniferous granitic ma...Multi-constraints are used in this paper to discuss the ΣCO_2 source in oreforming hydrothermal solution of granite-type uranium deposit in South China. The studies show that highly acidic and uraniferous granitic magma cannot produce the fluid rich in ΣCO_2. Controlled by three periods of crust extension and corresponding to three major periods of U-mineralization in South China respectively, the ΣCO_2 in each ore-forming hydrothermal solutions is all mantle-derived. Our studies reasonably explain why the mineralization did not occur immediately after the end of differentiation of the granitic magma rich in uranium, and why the ore-forming time of granite-type uranium deposit focuses on the time of crust extension after the formation of the uraniferous granites.展开更多
As for granite-type hydrothermal uranium deposit, the following phenomena have almost been recognized by all uranium geologists both in China and abroad.(1) Uranium mineralization presents a multi-period and simultane...As for granite-type hydrothermal uranium deposit, the following phenomena have almost been recognized by all uranium geologists both in China and abroad.(1) Uranium mineralization presents a multi-period and simultaneous feature in the same uranium mineralization zone. The data of mineralization age of most granite- type ura-展开更多
The Zhuxi W(Cu)skarn deposit,the world’s largest tungsten deposit is newly discovered in Jingdezhen city,northeastern Jiangxi province,China.It mainly occurs near the contact zone between the Yanshanian granites and ...The Zhuxi W(Cu)skarn deposit,the world’s largest tungsten deposit is newly discovered in Jingdezhen city,northeastern Jiangxi province,China.It mainly occurs near the contact zone between the Yanshanian granites and the Late Paleozoic carbonate rocks.Three types of mineralization including skarn type,altered granite type and quartz vein veinlet type orebodies have been observed.In this study,the 40Ar 39Ar age of hydrothermal muscovite coexisting with copper mineralization in the altered granite type orebody formed near the unconformity interface is determined by step-heating technology using CO2 laser.The plateau age,isochron age,and inverse isochron age of muscovite are(147.39±0.94)Ma,(147.2±1.5)Ma,and(147.1±1.5)Ma,respectively.These ages are almost identical to the ages of ore-related granite and other mineralization types in the Zhuxi W(Cu)deposit,indicating that the Cu mineralizations occurred at the shallow depth and near the unconformity interface are contemporaneous during the Late Jurassic.This further suggested that the acompanied W and Cu mineralization in the Zhuxi W(Cu)deposit which may be controlled by the magma source is enriched in both W and Cu.展开更多
New zircon U-Pb dates obtained by laser ablation inductively coupled plasma mass spectrometry（LA-ICP-MS）,whole-rock geochemical data and Sm-Nd and Rb-Sr isotopic data are presented for miarolitic alkaline granites,p...New zircon U-Pb dates obtained by laser ablation inductively coupled plasma mass spectrometry（LA-ICP-MS）,whole-rock geochemical data and Sm-Nd and Rb-Sr isotopic data are presented for miarolitic alkaline granites,porphyritic syenite and rhyolites of the Nianzishan A-type granitoid complex（NAGC）in the Great Xing’an Range-Songliao Basin in Northeast（NE）China.New crystallization ages of 112.95±0.93 and 114.1±1.71 Ma for granite and 118.6±0.51 Ma for porphyritic syenite were determined by high-precision LA-ICP-MS.The εNd（t）of the rocks range from +1.85 to+2.06,with Nd model ages(TDM1)from 671 to 821 Ma,indicating that the NAGC originated from juvenile source rocks and exhibits geochemical characteristics of A1-and AA-type granite which formed in an extensional setting.We attribute the magmatism to regional extension and lithospheric thinning caused by the subduction of the western Pacific Plate about 120 to 100 Ma.展开更多
文摘A growing number of oil and gas reservoirs have been discovered in granite and metamorphic crystallized rock areas. Statistics show that, about 157 oil and gas fields were found in crystallized bedrocks, with oil reserves of 5048x 10^8 t, and gas reserves of 2681x10^8m3. Among the discovered industrial oil and gas fields hosted in crystallized rocks, most occurred in granite rocks, occupying 40% in quantity and 75% in reserves, followed by those hosted in mafic and ultra-mafic rocks （about 3%）, and then tbllowed by those in volcanic rocks and metamorphic rocks.
基金Project supported by the National Natural Science Foundation of China, and by the Fund of Laboratory of Ore Deposit Geochemistry, Academia Sinica.
文摘Multi-constraints are used in this paper to discuss the ΣCO_2 source in oreforming hydrothermal solution of granite-type uranium deposit in South China. The studies show that highly acidic and uraniferous granitic magma cannot produce the fluid rich in ΣCO_2. Controlled by three periods of crust extension and corresponding to three major periods of U-mineralization in South China respectively, the ΣCO_2 in each ore-forming hydrothermal solutions is all mantle-derived. Our studies reasonably explain why the mineralization did not occur immediately after the end of differentiation of the granitic magma rich in uranium, and why the ore-forming time of granite-type uranium deposit focuses on the time of crust extension after the formation of the uraniferous granites.
文摘As for granite-type hydrothermal uranium deposit, the following phenomena have almost been recognized by all uranium geologists both in China and abroad.(1) Uranium mineralization presents a multi-period and simultaneous feature in the same uranium mineralization zone. The data of mineralization age of most granite- type ura-
基金Project(41873059)supported by the National Natural Science Foundation of ChinaProject(JGMEDB [2017]78)supported by the Jiangxi Geological and Mineral Exploration and Development Bureau Foundation,China+2 种基金Project(2011BAB04B02)supported by the National Science and Technology Support Plan Project,ChinaProject(201411035)supported by the Welfare Research Program of Ministry of Land and Resources,ChinaProject(20150013)supported by Jiangxi Provincial Geological Exploration Fund Management Center,China
文摘The Zhuxi W(Cu)skarn deposit,the world’s largest tungsten deposit is newly discovered in Jingdezhen city,northeastern Jiangxi province,China.It mainly occurs near the contact zone between the Yanshanian granites and the Late Paleozoic carbonate rocks.Three types of mineralization including skarn type,altered granite type and quartz vein veinlet type orebodies have been observed.In this study,the 40Ar 39Ar age of hydrothermal muscovite coexisting with copper mineralization in the altered granite type orebody formed near the unconformity interface is determined by step-heating technology using CO2 laser.The plateau age,isochron age,and inverse isochron age of muscovite are(147.39±0.94)Ma,(147.2±1.5)Ma,and(147.1±1.5)Ma,respectively.These ages are almost identical to the ages of ore-related granite and other mineralization types in the Zhuxi W(Cu)deposit,indicating that the Cu mineralizations occurred at the shallow depth and near the unconformity interface are contemporaneous during the Late Jurassic.This further suggested that the acompanied W and Cu mineralization in the Zhuxi W(Cu)deposit which may be controlled by the magma source is enriched in both W and Cu.
基金funded by the China Geological Survey (Nos. DD20160123 (DD-16-049, D1522), DD20160346, 1212011121075, 212010911028, 12120114020901)the National Natural Science Foundation of China (No.NSFC40802020)
文摘New zircon U-Pb dates obtained by laser ablation inductively coupled plasma mass spectrometry（LA-ICP-MS）,whole-rock geochemical data and Sm-Nd and Rb-Sr isotopic data are presented for miarolitic alkaline granites,porphyritic syenite and rhyolites of the Nianzishan A-type granitoid complex（NAGC）in the Great Xing’an Range-Songliao Basin in Northeast（NE）China.New crystallization ages of 112.95±0.93 and 114.1±1.71 Ma for granite and 118.6±0.51 Ma for porphyritic syenite were determined by high-precision LA-ICP-MS.The εNd（t）of the rocks range from +1.85 to+2.06,with Nd model ages(TDM1)from 671 to 821 Ma,indicating that the NAGC originated from juvenile source rocks and exhibits geochemical characteristics of A1-and AA-type granite which formed in an extensional setting.We attribute the magmatism to regional extension and lithospheric thinning caused by the subduction of the western Pacific Plate about 120 to 100 Ma.
