The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beisha...The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. （1） The regional distribution of gold deposits （and gold spots） is controlled by the ductile shear zone. （2） The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. （3） Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. （4） Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R＇-type and T-type ones. （5） Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. （6） There is a negative correlation between the gold abundance and susceptibility anlsotropy （P） of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.展开更多
Through the study of the oxidized zone of the Debao skarn-type Cu-Sn deposit in Guangxi, the authorshave found 14 arsenate minerals, most of which are for the first time reported in China. They are mainly Cuarsenate m...Through the study of the oxidized zone of the Debao skarn-type Cu-Sn deposit in Guangxi, the authorshave found 14 arsenate minerals, most of which are for the first time reported in China. They are mainly Cuarsenate minerals with subordinate Cu-Pb arsenate minerals and minor Fe-Pb-Ba varieties. Based on their paragenesis these minerals may be divided into the following series: (1) the clinoclasite-olivenite-cornwallite- cornubite- debaoite- copper silicarsenate association, (2) the scorodite- carminite- beudan-tite-bayldonite- duftite association, and (3) the scorodite-Ba-bearing pharmacosiderite- dussertite association. Arsenate minerals are formed generally in the oxidized zone of the sulfide-type deposits which lie in thewarm, humid and rainy torrid-subtropical zone with pH=6-8 and contain large amounts of arsenopyrite andcarbonate rocks.展开更多
Spatial-genetic relation of a polycomponent ore mineralization (Au, Ag, PGE, Cu, Pb, Zn, Ni) with dynamometamorphic complex, formed by the picrite-komatiite-tholeiite series rocks of Kelyana-Irokinda greenstone belt, ...Spatial-genetic relation of a polycomponent ore mineralization (Au, Ag, PGE, Cu, Pb, Zn, Ni) with dynamometamorphic complex, formed by the picrite-komatiite-tholeiite series rocks of Kelyana-Irokinda greenstone belt, is identified. Productivity of various ore mineralization morphostructural types (quartz-vein, zones of veining and sulfide dissemination) differing in mineral composition and content of useful components is considered. It is shown that the main industrial value is represented by veined and disseminated ores with relatively poor useful components content, but at the same time forming large-capacity ore zones. The occurrence extent, localization conditions and ore zones hyperthetical resources are favorable for the production of economically cost-effective open pit (quarry) mining operations. An effective sampling method is recommended to carry out the prospect and exploration of large-capacity deposits on the Yubileyny field and other similar to its Transbaikalia ore objects.展开更多
Zoning in ore bodies, ore deposits and ore regions are recognized as temporal-spatial structures generated by the dynamics of ore- forming processes. Viewed from the theory of dissipative structures, ore zoning is a k...Zoning in ore bodies, ore deposits and ore regions are recognized as temporal-spatial structures generated by the dynamics of ore- forming processes. Viewed from the theory of dissipative structures, ore zoning is a kind of self-organization phenomenon occurring in far from-equilibrium geochemical dynamic systems. Therefore,kinetic and dynamic approaches must be taken to reveal the mechanisms of ore zoning. Two dominant coupling processes leading to ore zoning——reaction-transport feedbacks and double-diffusive convection——are discussed.展开更多
The Manganese deposits of Andhra Pradesh are associated with a thick sequence of Precambrian rocks, belonging to Khondalite and Charnockite groups of Dharwar Supergroup that forms part of 2500 to 3000 m.y. old Eastern...The Manganese deposits of Andhra Pradesh are associated with a thick sequence of Precambrian rocks, belonging to Khondalite and Charnockite groups of Dharwar Supergroup that forms part of 2500 to 3000 m.y. old Eastern Ghat complex of India. The study area is the Manganese deposits of Vizianagram-Visakhapatnam Manganese Belt of Andhra Pradesh. The study area lies about 150 km NE of Visakhapatnam between 18°12′N - 18°30′N and 83°20′E - 83°45′E. The mineralization of Manganese ores is confined to different rock types, belonging to both Khondalite and Charnockite groups, where they are dispersed throughout the country rocks as small lenses, pockets, veins and irregular bodies of varying dimensions. Quartz, garnet, clay, limonite and apatite are the common gangue minerals in the Manganese ores. The presence of quartz, garnet and apatite brings down the grade of the ore. Ferruginous laterite and ochre generally work as capping of the Manganese deposits. The various Manganese ore minerals present in these deposits are indentified as 1) Primary minerals-braunite, bixbyite, vredenburgite, jacobsite and hausmannite, 2) secondary minerals-psilomelane, cryptomelane, hollandite, pyrolusite and wad. The primary ore minerals are considered to be syngenetic and regionally metamorphosed while, the associated secondary ore minerals are formed due to alteration of the primary ores.展开更多
Singhbhum Shear Zone is a highly mineralized zone having variety of minerals, predominantly those of uranium, copper and some sulphide minerals. From Remote Sensing data it is possible to decipher the regional litholo...Singhbhum Shear Zone is a highly mineralized zone having variety of minerals, predominantly those of uranium, copper and some sulphide minerals. From Remote Sensing data it is possible to decipher the regional lithology, tectonic fabric and also the geomorphic details of a terrain which aid precisely in targeting of metals and minerals. Mapping of mineralized zones can be done using Geospatial Technology in a GIS platform. The present study includes creation of various maps like lithological map, geomorphological map, contours and slope map using satellite data like IRS LISSIV and ASTER DEM which can be used to interprete and correlate the various mineral prospective zones in the study area. Even the alterations of the prevalent mineral zones can be mapped for further utilization strategies. The present work is based on the investigations being carried under ISROSAC Respond Project (Dept. of Space, Govt. of India SAC Code: OGP62, ISRO Code: 10/4/556).展开更多
The slope stability of the Itakpe Iron Ore Mine has been carried out using computer software, ROCKPACK III. One hundred and twenty three dip and dip direction values were obtained using compass clinometer. The Itakpe ...The slope stability of the Itakpe Iron Ore Mine has been carried out using computer software, ROCKPACK III. One hundred and twenty three dip and dip direction values were obtained using compass clinometer. The Itakpe Iron Ore Mine was divided into four benches;241 - 258 m, 263 - 275 m, 276 - 286 m and 308 - 312 m. Joints along the discontinuities were mapped. The data obtained were analyzed using ROCKPACK III. The results indicate that the discontinuities within the critical zone are potentially unstable and can lead to planar failure. The Markland test carried out for wedge failure indicates that the intersection of the discontinuities does not fall within the critical zone hence there cannot be any wedge failure of the slope within the level 241 - 258 m. The presence of discontinuities that plot within the toppling critical zone indicates that there is potential toppling failure on the slope at the 276 - 286 m level. In addition, the toppling failure test shows the absence of discontinuities that plot within the toppling critical zone and this indicates the absence of poten-tial toppling failure of the slope at the 308 - 312 m level. The result of the study will be useful to the man-agement of the Itakpe iron ore mine in having a proper understanding of the failure mechanism of the slopes.展开更多
基金This paper is supported by the National 305 Program (Nos. 2001BA609A-07-02, 2006BAB07B02-04)Research Foundation of former Ministry of Geology and Mineral Re-sources of China (No.96-21)
文摘The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. （1） The regional distribution of gold deposits （and gold spots） is controlled by the ductile shear zone. （2） The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and control the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. （3） Compresso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. （4） Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R＇-type and T-type ones. （5） Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming materials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. （6） There is a negative correlation between the gold abundance and susceptibility anlsotropy （P） of the altered mylonlte samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.
文摘Through the study of the oxidized zone of the Debao skarn-type Cu-Sn deposit in Guangxi, the authorshave found 14 arsenate minerals, most of which are for the first time reported in China. They are mainly Cuarsenate minerals with subordinate Cu-Pb arsenate minerals and minor Fe-Pb-Ba varieties. Based on their paragenesis these minerals may be divided into the following series: (1) the clinoclasite-olivenite-cornwallite- cornubite- debaoite- copper silicarsenate association, (2) the scorodite- carminite- beudan-tite-bayldonite- duftite association, and (3) the scorodite-Ba-bearing pharmacosiderite- dussertite association. Arsenate minerals are formed generally in the oxidized zone of the sulfide-type deposits which lie in thewarm, humid and rainy torrid-subtropical zone with pH=6-8 and contain large amounts of arsenopyrite andcarbonate rocks.
文摘Spatial-genetic relation of a polycomponent ore mineralization (Au, Ag, PGE, Cu, Pb, Zn, Ni) with dynamometamorphic complex, formed by the picrite-komatiite-tholeiite series rocks of Kelyana-Irokinda greenstone belt, is identified. Productivity of various ore mineralization morphostructural types (quartz-vein, zones of veining and sulfide dissemination) differing in mineral composition and content of useful components is considered. It is shown that the main industrial value is represented by veined and disseminated ores with relatively poor useful components content, but at the same time forming large-capacity ore zones. The occurrence extent, localization conditions and ore zones hyperthetical resources are favorable for the production of economically cost-effective open pit (quarry) mining operations. An effective sampling method is recommended to carry out the prospect and exploration of large-capacity deposits on the Yubileyny field and other similar to its Transbaikalia ore objects.
文摘Zoning in ore bodies, ore deposits and ore regions are recognized as temporal-spatial structures generated by the dynamics of ore- forming processes. Viewed from the theory of dissipative structures, ore zoning is a kind of self-organization phenomenon occurring in far from-equilibrium geochemical dynamic systems. Therefore,kinetic and dynamic approaches must be taken to reveal the mechanisms of ore zoning. Two dominant coupling processes leading to ore zoning——reaction-transport feedbacks and double-diffusive convection——are discussed.
文摘The Manganese deposits of Andhra Pradesh are associated with a thick sequence of Precambrian rocks, belonging to Khondalite and Charnockite groups of Dharwar Supergroup that forms part of 2500 to 3000 m.y. old Eastern Ghat complex of India. The study area is the Manganese deposits of Vizianagram-Visakhapatnam Manganese Belt of Andhra Pradesh. The study area lies about 150 km NE of Visakhapatnam between 18°12′N - 18°30′N and 83°20′E - 83°45′E. The mineralization of Manganese ores is confined to different rock types, belonging to both Khondalite and Charnockite groups, where they are dispersed throughout the country rocks as small lenses, pockets, veins and irregular bodies of varying dimensions. Quartz, garnet, clay, limonite and apatite are the common gangue minerals in the Manganese ores. The presence of quartz, garnet and apatite brings down the grade of the ore. Ferruginous laterite and ochre generally work as capping of the Manganese deposits. The various Manganese ore minerals present in these deposits are indentified as 1) Primary minerals-braunite, bixbyite, vredenburgite, jacobsite and hausmannite, 2) secondary minerals-psilomelane, cryptomelane, hollandite, pyrolusite and wad. The primary ore minerals are considered to be syngenetic and regionally metamorphosed while, the associated secondary ore minerals are formed due to alteration of the primary ores.
文摘Singhbhum Shear Zone is a highly mineralized zone having variety of minerals, predominantly those of uranium, copper and some sulphide minerals. From Remote Sensing data it is possible to decipher the regional lithology, tectonic fabric and also the geomorphic details of a terrain which aid precisely in targeting of metals and minerals. Mapping of mineralized zones can be done using Geospatial Technology in a GIS platform. The present study includes creation of various maps like lithological map, geomorphological map, contours and slope map using satellite data like IRS LISSIV and ASTER DEM which can be used to interprete and correlate the various mineral prospective zones in the study area. Even the alterations of the prevalent mineral zones can be mapped for further utilization strategies. The present work is based on the investigations being carried under ISROSAC Respond Project (Dept. of Space, Govt. of India SAC Code: OGP62, ISRO Code: 10/4/556).
文摘The slope stability of the Itakpe Iron Ore Mine has been carried out using computer software, ROCKPACK III. One hundred and twenty three dip and dip direction values were obtained using compass clinometer. The Itakpe Iron Ore Mine was divided into four benches;241 - 258 m, 263 - 275 m, 276 - 286 m and 308 - 312 m. Joints along the discontinuities were mapped. The data obtained were analyzed using ROCKPACK III. The results indicate that the discontinuities within the critical zone are potentially unstable and can lead to planar failure. The Markland test carried out for wedge failure indicates that the intersection of the discontinuities does not fall within the critical zone hence there cannot be any wedge failure of the slope within the level 241 - 258 m. The presence of discontinuities that plot within the toppling critical zone indicates that there is potential toppling failure on the slope at the 276 - 286 m level. In addition, the toppling failure test shows the absence of discontinuities that plot within the toppling critical zone and this indicates the absence of poten-tial toppling failure of the slope at the 308 - 312 m level. The result of the study will be useful to the man-agement of the Itakpe iron ore mine in having a proper understanding of the failure mechanism of the slopes.
