Seventy-three large-superlarge deposits in China were formed in 4 metallogenic epochs, and located in 6 metallogenic domains. By combing their time-space distribution and the relevant data of crustal thickness, we dis...Seventy-three large-superlarge deposits in China were formed in 4 metallogenic epochs, and located in 6 metallogenic domains. By combing their time-space distribution and the relevant data of crustal thickness, we discuss the control conditions of deep tectonics on superlarge deposits. The various spatial variation of the crustal thickness where deposits locate is closely related to their different tectonic setting. The crustal thickness of the region where deposits are in the Precatnbrian metallogenic epoch is 37.1 km and shows double-peak distribution, which is related to the different tectonic-mineralization processes in the Tarim-North China and Yangtze metallogenic domains. The crustal thickness of the region where deposits are in the Paleoproterozoic metallogenic epoch is 43.4 km and shows normal distribution, which is the result of 'pure' mineralization setting. The crustal thickness of the region where deposits are in the Late Palaeozoic-Early Mesozoic metallogenic epoch is about 41.2 km and shows multi-peak distribution, which can be related with dispersing distribution in the metallogenic domain of these superlarge deposits. The crustal thickness of the region where deposits are in the post-Indosinian metallogenic epoch is 37.3 km, and shows skew distribution, which resulted from different tectonic settings in eastern and western China.展开更多
Extensive transgression of lake water occurred during the Cretaceous Qingshankou Stage and the Nengjiang Stage in the Songliao basin, forming widespread deep-water deposits. Eleven types of microfacies of deep-water d...Extensive transgression of lake water occurred during the Cretaceous Qingshankou Stage and the Nengjiang Stage in the Songliao basin, forming widespread deep-water deposits. Eleven types of microfacies of deep-water deposits have been recognized in the continuous core rocks from the SKII, including mudstone of still water, marlite, dolostone, off shale, volcanic ashes, turbidite, slump sediment, tempestite, seismite, ostracoda limestone and sparry carbonate, which are divided into two types: microfacies generated due to gradually changing environments (Ⅰ) and microfacies generated due to geological events (Ⅱ). Type Ⅰ is composed of some special fine grain sediments such as marlite, dolomite stone and oil shale as well as mudstone and Type Ⅱ is composed of some sediments related to geological events, such as volcanic ashes, turbiditie, slump sediment, tempestite, seismite, ostracoda limestone. The formation of sparry carbonate may be controlled by factors related to both environments and events. Generally, mudstone sediments of still water can be regarded as background sediments, and the rest sediments are all event sediments, which have unique forming models, which may reflect controlling effects of climatics and tectonics.展开更多
Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of thi...Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of this shallow-covered area and delineate deep-seated gold prospecting targets. In this region, altogether 12 faults exert critical control on distribution of three types of Early Precambrian metamorphic rock series, i.e. those in the metamorphic rock area, in the granitic rock area underlying the metamorphic rock, and in the remnant metamorphic rock area in granites, respectively. Additionally, the faults have major effects on distribution of four Mesozoic Linglong rock bodies of granite, i.e. the Cangshang, Liangguo, Zhuqiao-Miaojia and Jincheng granites. The Sanshandao and Jiaojia Faults are two well-known regional ore-controlling faults; they have opposite dip direction, and intersect at a depth of 4500 m. Fracture alteration zones have striking geophysical differences relative to the surrounding county rocks. The two faults extend down along dip direction in a gentle wave form, and appear at some steps with different dips. These steps comprise favorable gold prospecting areas, consistent with a step metallogenic model. Six deep-seated gold-prospecting targets are delineated, i.e. Jincheng-Qianchenjia, Xiaoxizhuang-Zhaoxian, Xiyou-Wujiazhuangzi, Xiangyangling-Xinlicun, Panjiawuzi and Miaojia-Pinglidian.展开更多
Deep-water gravity flows are one of the most important sediment transport mechanisms on Earth. After 60 years of study, significant achievements have been made in terms of classification schemes, genetic mechanisms, a...Deep-water gravity flows are one of the most important sediment transport mechanisms on Earth. After 60 years of study, significant achievements have been made in terms of classification schemes, genetic mechanisms, and depositional models of deep-water gravity flows. The research history of deep-water gravity flows can be divided into five stages: incipience of turbidity current theory; formation of turbidity current theory; development of deep-water gravity flow theory; improvement and perfection of deep-water gravity flow theory; and comprehensive development of deep-water gravity flow theory. Currently, three primary classification schemes based on the sediment support mechanism, the rheology and transportation process, and the integration of sediment support mechanisms, rheology, sedimentary characteristics, and flow state are commonly used.Different types of deep-water gravity flow events form different types of gravity flow deposits. Sediment slump retransportation mainly forms muddy debris flows, sandy debris flows, and surge-like turbidity currents. Resuspension of deposits by storms leads to quasi-steady hyperpycnal turbidity currents (hyperpycnal flows). Sustainable sediment supplies mainly generate muddy debris flows, sandy debris flows, and hyperpycnal flows. Deep-water fans, which are commonly controlled by debris flows and hyperpycnal flows, are triggered by sustainable sediment supply; in contrast, deep-water slope sedimentary deposits consist mainly of debris flows that are triggered by the retransportation of sediment slumps and deep-water fine-grained sedimentary deposits are derived primarily from fine- grained hyperpycnal flows that are triggered by the resuspension of storm deposits. Harmonization of classification schemes, transformation between different types of gravity flow deposit, and monitoring and reproduction of the sedimentary processes of deep-water gravity flows as well as a source-to-sink approach to document the evolution and deposition of deep-water gravity flows are the most important research aspects for future studies of deep-water gravity flows study in the future.展开更多
The depth is important for ore finding in Jiaodong gold deposit. However, many geologists are still discussing how to confirm the depth for the tectonic and metallogenesis formation. The authors of this paper propose ...The depth is important for ore finding in Jiaodong gold deposit. However, many geologists are still discussing how to confirm the depth for the tectonic and metallogenesis formation. The authors of this paper propose a new method-the correction of metallogenic depth via its structure to calculate the depth. This method, based on the crust rock in a solid stress state, emphasizes the elastic pattern rather than the static fluid pattern. In addition, this method is more appropriate to the actual situation in the crust than the method of weight/special weight. The authors of this paper illustrating, with the Jiaodong gold deposit as an example, the metallogenic depth correction via structure conclude that the depth of the most deposits, lower than 4-6 km, is often 2.5 km. Therefore, the authors suggest that there exists a second enrichment belt and that ore resources are more potential at the belt of Jiaodong area. These results have been demonstrated by years of exploration.展开更多
The Cambrian-Ordovician rocks in southwestern Jiangxi are mainly composed of deep-water deposits, in which 5 facies have been recognized: sandstone facies, sandstone-mudstone facies, siltstone-mudstone facies, mudston...The Cambrian-Ordovician rocks in southwestern Jiangxi are mainly composed of deep-water deposits, in which 5 facies have been recognized: sandstone facies, sandstone-mudstone facies, siltstone-mudstone facies, mudstone (slate)facies, and chert facies. They are of turbidity current origin and are related to pelagic and hemipelagic deposits. In the light of facies distribution, the Cambrian-Ordovician deposits can be classified into 3 facies associations formed in middle fan, outer fan and deep-sea plain environments respectively. The 3 different orders of vertical cycles in the stratigraphic sequence are considered to be controlled by factors such as sea-level fluctuation, basin subsidence and submarine fan progradation. The tectonic setting of the sedimentary basin is interpreted as passive continental margin based on the chemical composition analysis of the sandstone.展开更多
A study of deep penetrating geochemistry--the surface exploration techniques for finding concealed mineral deposits--was carried out over the Spence porphyry copper deposit in Chile by Australian, Canadian and Chinese...A study of deep penetrating geochemistry--the surface exploration techniques for finding concealed mineral deposits--was carried out over the Spence porphyry copper deposit in Chile by Australian, Canadian and Chinese laboratories using selective weak leach methods and is briefly reviewed here. Erratic and weak copper anomalies were obtained above the Spence deposit, which is concealed below a thick piedmont gravel cover. In the literature, such patterns are common in most of the weak selective leach studies carried out over known buried deposits. During exploration in unknown area, such weak leach techniques lead to some success and many dry holes. In this paper, stronger selective leaching methods are developed for oxides and sulfides, which may be the stable end products transformed and accumulated by a mobile precursor phase carried upward through the overburden by gas or water through long spans of geological time. The data obtained by the methods developed in this paper produced more significant and consistent anomalous data than previous efforts. Consequently, the leach approaches described here may increase the effectiveness of deep penetrating geochemistry in exploration for con- cealed ore deposits.展开更多
The eastern Hebei Province of China is one of the major concentrating areas of gold mineralization in eastern China, which is an important part of the circum Pacific magmatic tectonic metallogenic belt. There are t...The eastern Hebei Province of China is one of the major concentrating areas of gold mineralization in eastern China, which is an important part of the circum Pacific magmatic tectonic metallogenic belt. There are three types of gold deposits in terms of the characteristics of host rocks. Jinchangyu type gold deposit is situated in the Archean metamorphic basement. Yuerya type gold deposit occurs within the Yanshanian granite. Lengkou (or Wanzhuang ) type gold deposit is located within the covering strata of the Mesoproterozoic dolomitite. These 3 types of gold deposits are very similar in many respects. These deposits formed at Mesozoic and their spatial distribution is closely related to Yanshanian granite. The mineralization characteristics of these gold deposits are very similar. The characteristics of sulfur isotopic and lead isotopic compositions show that the gold deposits in this area are derived from the mantle and deep crust, and are related to Mesozoic magmatism. The gold deposits in this area are believed to be the products of crust mantle exchange and resulted from multistage gold mineralization. Finally a mineralization model of gold deposit in eastern Hebei of China is proposed.展开更多
Based on the geology and geochemistry of gold-bearing quartz veins in the Jiudian gold deposit of Pingdu,Shandong Province,the geological and geochemical indicators of occurrence of deep-seated ore bodies in the Jiudi...Based on the geology and geochemistry of gold-bearing quartz veins in the Jiudian gold deposit of Pingdu,Shandong Province,the geological and geochemical indicators of occurrence of deep-seated ore bodies in the Jiudian gold deposit have been summarized.Extent occurrence of wide,intensive,varied alteration zones around the gold-bearing quartz veins and continual presence of diorite porphyrite and lamprophyry indicate the probable occurrence of deep-seated ore bodies at depth of gold lodes.As,Sb and Hg belong to the head halo elements, and their anomalies could reveal the probable occurrence of the deep-seated ore bodies below.展开更多
基金the Chinese Academy of Sciences (No. KXCX2-109) National Natural Science Foundation of China (No. 40304007 ,No.40172036)+1 种基金"Key Project of Science and Technology Research”(No. 01037) China Postdoctoral Science Foundation (No. 2003033238).
文摘Seventy-three large-superlarge deposits in China were formed in 4 metallogenic epochs, and located in 6 metallogenic domains. By combing their time-space distribution and the relevant data of crustal thickness, we discuss the control conditions of deep tectonics on superlarge deposits. The various spatial variation of the crustal thickness where deposits locate is closely related to their different tectonic setting. The crustal thickness of the region where deposits are in the Precatnbrian metallogenic epoch is 37.1 km and shows double-peak distribution, which is related to the different tectonic-mineralization processes in the Tarim-North China and Yangtze metallogenic domains. The crustal thickness of the region where deposits are in the Paleoproterozoic metallogenic epoch is 43.4 km and shows normal distribution, which is the result of 'pure' mineralization setting. The crustal thickness of the region where deposits are in the Late Palaeozoic-Early Mesozoic metallogenic epoch is about 41.2 km and shows multi-peak distribution, which can be related with dispersing distribution in the metallogenic domain of these superlarge deposits. The crustal thickness of the region where deposits are in the post-Indosinian metallogenic epoch is 37.3 km, and shows skew distribution, which resulted from different tectonic settings in eastern and western China.
文摘Extensive transgression of lake water occurred during the Cretaceous Qingshankou Stage and the Nengjiang Stage in the Songliao basin, forming widespread deep-water deposits. Eleven types of microfacies of deep-water deposits have been recognized in the continuous core rocks from the SKII, including mudstone of still water, marlite, dolostone, off shale, volcanic ashes, turbidite, slump sediment, tempestite, seismite, ostracoda limestone and sparry carbonate, which are divided into two types: microfacies generated due to gradually changing environments (Ⅰ) and microfacies generated due to geological events (Ⅱ). Type Ⅰ is composed of some special fine grain sediments such as marlite, dolomite stone and oil shale as well as mudstone and Type Ⅱ is composed of some sediments related to geological events, such as volcanic ashes, turbiditie, slump sediment, tempestite, seismite, ostracoda limestone. The formation of sparry carbonate may be controlled by factors related to both environments and events. Generally, mudstone sediments of still water can be regarded as background sediments, and the rest sediments are all event sediments, which have unique forming models, which may reflect controlling effects of climatics and tectonics.
基金the Geological Science and technology foundation of Shandong Provincial Bureau of Geology and Mineral Resources (Grant No. 20080037)
文摘Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of this shallow-covered area and delineate deep-seated gold prospecting targets. In this region, altogether 12 faults exert critical control on distribution of three types of Early Precambrian metamorphic rock series, i.e. those in the metamorphic rock area, in the granitic rock area underlying the metamorphic rock, and in the remnant metamorphic rock area in granites, respectively. Additionally, the faults have major effects on distribution of four Mesozoic Linglong rock bodies of granite, i.e. the Cangshang, Liangguo, Zhuqiao-Miaojia and Jincheng granites. The Sanshandao and Jiaojia Faults are two well-known regional ore-controlling faults; they have opposite dip direction, and intersect at a depth of 4500 m. Fracture alteration zones have striking geophysical differences relative to the surrounding county rocks. The two faults extend down along dip direction in a gentle wave form, and appear at some steps with different dips. These steps comprise favorable gold prospecting areas, consistent with a step metallogenic model. Six deep-seated gold-prospecting targets are delineated, i.e. Jincheng-Qianchenjia, Xiaoxizhuang-Zhaoxian, Xiyou-Wujiazhuangzi, Xiangyangling-Xinlicun, Panjiawuzi and Miaojia-Pinglidian.
基金National Natural Science Foundation of China (Grant No.U1262203)the National Science and Technology Special Grant (Grant No.2011ZX05006-003)the Fundamental Research Funds for the Central Universities (Grant No.14CX06070A)
文摘Deep-water gravity flows are one of the most important sediment transport mechanisms on Earth. After 60 years of study, significant achievements have been made in terms of classification schemes, genetic mechanisms, and depositional models of deep-water gravity flows. The research history of deep-water gravity flows can be divided into five stages: incipience of turbidity current theory; formation of turbidity current theory; development of deep-water gravity flow theory; improvement and perfection of deep-water gravity flow theory; and comprehensive development of deep-water gravity flow theory. Currently, three primary classification schemes based on the sediment support mechanism, the rheology and transportation process, and the integration of sediment support mechanisms, rheology, sedimentary characteristics, and flow state are commonly used.Different types of deep-water gravity flow events form different types of gravity flow deposits. Sediment slump retransportation mainly forms muddy debris flows, sandy debris flows, and surge-like turbidity currents. Resuspension of deposits by storms leads to quasi-steady hyperpycnal turbidity currents (hyperpycnal flows). Sustainable sediment supplies mainly generate muddy debris flows, sandy debris flows, and hyperpycnal flows. Deep-water fans, which are commonly controlled by debris flows and hyperpycnal flows, are triggered by sustainable sediment supply; in contrast, deep-water slope sedimentary deposits consist mainly of debris flows that are triggered by the retransportation of sediment slumps and deep-water fine-grained sedimentary deposits are derived primarily from fine- grained hyperpycnal flows that are triggered by the resuspension of storm deposits. Harmonization of classification schemes, transformation between different types of gravity flow deposit, and monitoring and reproduction of the sedimentary processes of deep-water gravity flows as well as a source-to-sink approach to document the evolution and deposition of deep-water gravity flows are the most important research aspects for future studies of deep-water gravity flows study in the future.
文摘The depth is important for ore finding in Jiaodong gold deposit. However, many geologists are still discussing how to confirm the depth for the tectonic and metallogenesis formation. The authors of this paper propose a new method-the correction of metallogenic depth via its structure to calculate the depth. This method, based on the crust rock in a solid stress state, emphasizes the elastic pattern rather than the static fluid pattern. In addition, this method is more appropriate to the actual situation in the crust than the method of weight/special weight. The authors of this paper illustrating, with the Jiaodong gold deposit as an example, the metallogenic depth correction via structure conclude that the depth of the most deposits, lower than 4-6 km, is often 2.5 km. Therefore, the authors suggest that there exists a second enrichment belt and that ore resources are more potential at the belt of Jiaodong area. These results have been demonstrated by years of exploration.
文摘The Cambrian-Ordovician rocks in southwestern Jiangxi are mainly composed of deep-water deposits, in which 5 facies have been recognized: sandstone facies, sandstone-mudstone facies, siltstone-mudstone facies, mudstone (slate)facies, and chert facies. They are of turbidity current origin and are related to pelagic and hemipelagic deposits. In the light of facies distribution, the Cambrian-Ordovician deposits can be classified into 3 facies associations formed in middle fan, outer fan and deep-sea plain environments respectively. The 3 different orders of vertical cycles in the stratigraphic sequence are considered to be controlled by factors such as sea-level fluctuation, basin subsidence and submarine fan progradation. The tectonic setting of the sedimentary basin is interpreted as passive continental margin based on the chemical composition analysis of the sandstone.
基金the Ministry of Land Resources and the Ministry of Science and Technology for the research funding of the projects:SinoProbe 04,973 Project 2007CB411406 and 863 Project 2007AA06Z133
文摘A study of deep penetrating geochemistry--the surface exploration techniques for finding concealed mineral deposits--was carried out over the Spence porphyry copper deposit in Chile by Australian, Canadian and Chinese laboratories using selective weak leach methods and is briefly reviewed here. Erratic and weak copper anomalies were obtained above the Spence deposit, which is concealed below a thick piedmont gravel cover. In the literature, such patterns are common in most of the weak selective leach studies carried out over known buried deposits. During exploration in unknown area, such weak leach techniques lead to some success and many dry holes. In this paper, stronger selective leaching methods are developed for oxides and sulfides, which may be the stable end products transformed and accumulated by a mobile precursor phase carried upward through the overburden by gas or water through long spans of geological time. The data obtained by the methods developed in this paper produced more significant and consistent anomalous data than previous efforts. Consequently, the leach approaches described here may increase the effectiveness of deep penetrating geochemistry in exploration for con- cealed ore deposits.
文摘The eastern Hebei Province of China is one of the major concentrating areas of gold mineralization in eastern China, which is an important part of the circum Pacific magmatic tectonic metallogenic belt. There are three types of gold deposits in terms of the characteristics of host rocks. Jinchangyu type gold deposit is situated in the Archean metamorphic basement. Yuerya type gold deposit occurs within the Yanshanian granite. Lengkou (or Wanzhuang ) type gold deposit is located within the covering strata of the Mesoproterozoic dolomitite. These 3 types of gold deposits are very similar in many respects. These deposits formed at Mesozoic and their spatial distribution is closely related to Yanshanian granite. The mineralization characteristics of these gold deposits are very similar. The characteristics of sulfur isotopic and lead isotopic compositions show that the gold deposits in this area are derived from the mantle and deep crust, and are related to Mesozoic magmatism. The gold deposits in this area are believed to be the products of crust mantle exchange and resulted from multistage gold mineralization. Finally a mineralization model of gold deposit in eastern Hebei of China is proposed.
基金Supported by Project of China Geological Survey(No.1212011085480 )Key Scientific and Technological Development Project of Jilin Province (No.20090479)
文摘Based on the geology and geochemistry of gold-bearing quartz veins in the Jiudian gold deposit of Pingdu,Shandong Province,the geological and geochemical indicators of occurrence of deep-seated ore bodies in the Jiudian gold deposit have been summarized.Extent occurrence of wide,intensive,varied alteration zones around the gold-bearing quartz veins and continual presence of diorite porphyrite and lamprophyry indicate the probable occurrence of deep-seated ore bodies at depth of gold lodes.As,Sb and Hg belong to the head halo elements, and their anomalies could reveal the probable occurrence of the deep-seated ore bodies below.