There are two main types of iron deposits in the Middle-Lower Yangtze Valley district.Both of them underwent post-magmatic hydrothermal processes during ore formation.Iron in the hydrothermal ore bodies was derived la...There are two main types of iron deposits in the Middle-Lower Yangtze Valley district.Both of them underwent post-magmatic hydrothermal processes during ore formation.Iron in the hydrothermal ore bodies was derived largely through mobilization from substantially consolidated diroitic intrusives.Wall-roch alteration zonation indicates that iron-mobilizing hydrothermal fluids evolved in a trend of decreasing alkalinity,which is suggested by regularly distributed wall-rock alterations formed by iron-mobilizing hydrothermal fluids and is in contradiction with the current chloride,chloride complex and bicarbonate models for iron mobilization.The close association of carbonatization with iron ores and the high concentrations of reduced gases such as CO,CH4 and H2 in fluid inclusions suggest that iron is most probably transported in the form of iron carbonyls during post-magmatic hydrothermal processes. In the light of the iron carbonyl mobilization model,explanations are made of the constraints on ores of some geologic factors such as melanocratic alteration,carbonatization,carbonate strata,structural fractures,cyptoexplosive pipes and embryo ores.展开更多
文摘There are two main types of iron deposits in the Middle-Lower Yangtze Valley district.Both of them underwent post-magmatic hydrothermal processes during ore formation.Iron in the hydrothermal ore bodies was derived largely through mobilization from substantially consolidated diroitic intrusives.Wall-roch alteration zonation indicates that iron-mobilizing hydrothermal fluids evolved in a trend of decreasing alkalinity,which is suggested by regularly distributed wall-rock alterations formed by iron-mobilizing hydrothermal fluids and is in contradiction with the current chloride,chloride complex and bicarbonate models for iron mobilization.The close association of carbonatization with iron ores and the high concentrations of reduced gases such as CO,CH4 and H2 in fluid inclusions suggest that iron is most probably transported in the form of iron carbonyls during post-magmatic hydrothermal processes. In the light of the iron carbonyl mobilization model,explanations are made of the constraints on ores of some geologic factors such as melanocratic alteration,carbonatization,carbonate strata,structural fractures,cyptoexplosive pipes and embryo ores.
