Longtoushan Sn-polymetal deposit is a large-scale deposit of high-tenor. The ore-bodies occur in reef limestone of middle Devonian. There is much anthraxolite in reef limestone and ore-bodies. The anthraxolite is the ...Longtoushan Sn-polymetal deposit is a large-scale deposit of high-tenor. The ore-bodies occur in reef limestone of middle Devonian. There is much anthraxolite in reef limestone and ore-bodies. The anthraxolite is the postmature result of oil-gas' thermal metamorphism. The close relationship of anthraxolite and Sn-polymetal deposit reveals the space-time relation between oil-gas evolution and Sn-polymetal mineralization. Sulfur isotope of Longtoushan deposit is close to oil's sulfur in Devonian, which indicates obvious relationship between the sulfur's source of deposit and oil-gas' activity. The forming of Longtoushan deposit relates to exhalative-sedimentary mineralization in Devonian. Because of the favorable hydrocarbon-forming condition of Longtoushan reef and surrounding basin facies' black shale and peat, coupling of ore-formation and hydrocarbon-forming occurs in seabed's hydrothermal convection. The distributing of ore-forming elements indicates the presence of hydrothermal convection system. The thermal fluid containing organic matters conduces to Sn-polymetal elements' activation and transfer, and provides catalyzing condition to the transforming from SO42- to S2-. The erosion action of brine containing organic acid to reef limestone induces the growing of crannies and karst's caverns, which provides advantageous space to Sn-polymetal mineralization. The heat source of mineralization provides thermocatalysis condition to hydrocarbon-forming. When the circulatory fluid containing oil-gas enters the high-temperature region(＞150 ℃ ), the oil-gas is decomposed and anthraxolite comes into being.展开更多
The study area is part of the Urumieh–Dokhtar volcanic arc that a large part of its surface is covered by extrusive Igneous rocks(tuff,intermediate lavas and ignimbrites sheets),plutonic igneous(diorite and granodior...The study area is part of the Urumieh–Dokhtar volcanic arc that a large part of its surface is covered by extrusive Igneous rocks(tuff,intermediate lavas and ignimbrites sheets),plutonic igneous(diorite and granodiorite)and semi-deep stones(dyke and sill).Studied samples are situated in calc-alkaline domain of magmatic series diagrams.Harker diagrams show the fractional crystallization of Clinopyroxene,amphibole,plagioclase,alkali feldspars and opaque minerals(ilmenite Titano-magnetite,ilmenite and rutile).In spider diagrams,light rare earth elements(LREE)are enriched compared to heavy rare earth elements(HREE),and HFS elements(Ti,Nb)show negative anomaly and LFS elements(Cs,K,Pb)show positive anomaly,showing that it is a distinct characteristic of subduction zones.Skarns of the area mainly are of exoskarns and are rich in plagioclase,microcline,amphibole,biotite and epidote.Skarn is enriched of iron,copper,molybdenum,vanadium,lead,zinc and silver.Deposits of barite in the area show characteristics of volcanic-sedimentary barites and are associated to ore-bearing hydrothermal solutions.Using satellite images and processing information,four areas with high mineral potential are identified in the area.展开更多
For minerals containing multivalent elements,their stabilities depend not only on pressure(P),temperature(T),and bulk chemical composition,but also the redox state.This applies to many ore forming minerals,such that t...For minerals containing multivalent elements,their stabilities depend not only on pressure(P),temperature(T),and bulk chemical composition,but also the redox state.This applies to many ore forming minerals,such that the redox state and its fluctuations in hydrothermal systems have long been considered as important controlling factors for the transport and deposition of ores.展开更多
文摘Longtoushan Sn-polymetal deposit is a large-scale deposit of high-tenor. The ore-bodies occur in reef limestone of middle Devonian. There is much anthraxolite in reef limestone and ore-bodies. The anthraxolite is the postmature result of oil-gas' thermal metamorphism. The close relationship of anthraxolite and Sn-polymetal deposit reveals the space-time relation between oil-gas evolution and Sn-polymetal mineralization. Sulfur isotope of Longtoushan deposit is close to oil's sulfur in Devonian, which indicates obvious relationship between the sulfur's source of deposit and oil-gas' activity. The forming of Longtoushan deposit relates to exhalative-sedimentary mineralization in Devonian. Because of the favorable hydrocarbon-forming condition of Longtoushan reef and surrounding basin facies' black shale and peat, coupling of ore-formation and hydrocarbon-forming occurs in seabed's hydrothermal convection. The distributing of ore-forming elements indicates the presence of hydrothermal convection system. The thermal fluid containing organic matters conduces to Sn-polymetal elements' activation and transfer, and provides catalyzing condition to the transforming from SO42- to S2-. The erosion action of brine containing organic acid to reef limestone induces the growing of crannies and karst's caverns, which provides advantageous space to Sn-polymetal mineralization. The heat source of mineralization provides thermocatalysis condition to hydrocarbon-forming. When the circulatory fluid containing oil-gas enters the high-temperature region(＞150 ℃ ), the oil-gas is decomposed and anthraxolite comes into being.
文摘The study area is part of the Urumieh–Dokhtar volcanic arc that a large part of its surface is covered by extrusive Igneous rocks(tuff,intermediate lavas and ignimbrites sheets),plutonic igneous(diorite and granodiorite)and semi-deep stones(dyke and sill).Studied samples are situated in calc-alkaline domain of magmatic series diagrams.Harker diagrams show the fractional crystallization of Clinopyroxene,amphibole,plagioclase,alkali feldspars and opaque minerals(ilmenite Titano-magnetite,ilmenite and rutile).In spider diagrams,light rare earth elements(LREE)are enriched compared to heavy rare earth elements(HREE),and HFS elements(Ti,Nb)show negative anomaly and LFS elements(Cs,K,Pb)show positive anomaly,showing that it is a distinct characteristic of subduction zones.Skarns of the area mainly are of exoskarns and are rich in plagioclase,microcline,amphibole,biotite and epidote.Skarn is enriched of iron,copper,molybdenum,vanadium,lead,zinc and silver.Deposits of barite in the area show characteristics of volcanic-sedimentary barites and are associated to ore-bearing hydrothermal solutions.Using satellite images and processing information,four areas with high mineral potential are identified in the area.
文摘For minerals containing multivalent elements,their stabilities depend not only on pressure(P),temperature(T),and bulk chemical composition,but also the redox state.This applies to many ore forming minerals,such that the redox state and its fluctuations in hydrothermal systems have long been considered as important controlling factors for the transport and deposition of ores.
