摘要
The Fankou Pb-Zn ore deposit occurs in Devonian and Carboniferous carbonate rocks.This deposit was thought to be a hydrothermal ore deposit related to a granite,but the present research suggests that it is a stratabound,stratiform mineral deposit.As a result of geological studies,primary sedimentary and later replacement features were found.Some ore bodies are concordant with the host rocks,but most are discrodant lenses and veins in the carbonate rocks,Thus there are two types of ore,primary sedimentary and later replaeement,The replacement type is very common.Isotopic studies indicate that most of the Pb and S are sedimentary origin,but part of Pb is of radiogenesis.possibly introduced during later.replacement.A regional geochemical survey indicates that the Pb and Zn contents of the Fankon region are respectively 1.5and 3 times higher than the world average.Only a few one-phase liquid inclusions were found in the primary sedimentary type.Gas-liquid inclusions were found in the replacement type but not in the primary sedimentary type.The fluid which bad replaced the primary sedimentary rocks had temperatures of 100°-200℃ and a salinity of 3-6wt.% NaCl equiv.Under the action of such fluid the original sedimentary rocks were replaced,forming the present ore deposit.
The Fankou Pb-Zn ore deposit occurs in Devonian and Carboniferous carbonate rocks. This deposit was thought to be a hydrothermal ore deposit related to a granite, but the present research suggests that it is a stratabound, stratiform mineral deposit. As a result of geological studies, primary sedimentary and later replacement features were found. Some ore bodies are concordant with the host rocks, but most are discordant lenses and veins in the carbonate rocks. Thus there are two types of ore, primary sedimentary and later replacement. The replacement type is very common. Isotopic studies indicate that most of the Pb and S are of sedimentary origin, but part of Pb is of radiogenesis, possibly introduced during later replacement. A regional ge-ochemical survey indicates that the Pb and Zn contents of the Fankou region are respectively 1.5 and 3 times higher than the world average. Only a few one-phase liquid inclusions were found in the primary sedimentary type. Gas-liquid inclusions were found in the replacement type but not in the primary sedimentary type. The fluid which had replaced the primary sedimentary rocks had temperatures of 100°-200℃ and a salinity of 3-6wt.% NaCl equiv. Under the action of such fluid the original sedimentary rocks were replaced, forming the present ore deposit.
出处
《地球化学》
CAS
1984年第4期357-365,405-407,共12页
Geochimica
