The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large c...The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in China, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O (K1≥1.2). Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cu, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O (K2≥1.2). Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization: (a) Cu-Au mineralization; (b) W-Mo mineralization; and (c) silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows: Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as (Ag*Zn)D/(Mo×W)D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth.展开更多
Grade-tonnage model is one of the research frontiers of systematical exploration theory. Based on the “Reserve Database of Mineral Resources in China (1997)”, this paper establishes the geological model, grade model...Grade-tonnage model is one of the research frontiers of systematical exploration theory. Based on the “Reserve Database of Mineral Resources in China (1997)”, this paper establishes the geological model, grade model, tonnage model, grade-tonnage model and tonnage-sequence model of contact metasomatic copper deposits in China. The mathematical properties of these models are described in detail.展开更多
THE Kangdian region is a middle Proterozoic continental rift basin that extends between longitudes 101°30’and 103°20’. There are a series of sedimentary strata, named Xiaoqingshan Formation, Yinmin Forma- ...THE Kangdian region is a middle Proterozoic continental rift basin that extends between longitudes 101°30’and 103°20’. There are a series of sedimentary strata, named Xiaoqingshan Formation, Yinmin Forma- tion, and Luoxue Formation. The strata were metamorphosed and deformed in Jinning tectonic event between approximately 850 and 750 Ma. There are many lode-copper deposits in the Kangdian region. Xiaoqingshan is a typical one among of them. The orebodies of the deposit occurs in veins and the hostrocks of the deposit are sericite-phyllite and sericite-slate. The deposit is characterized by large-scale pervasive sodium metasomatism (PSM). It has been identified that albite replaced sericite and chlorite of the original rocks during the PSM.As a result, the pelites were transformed into albitolite, which consists of albite totally. Mass balancecalculations show that the PSM process involved addition of large amount of Na<sub>2</sub>O and SiO<sub>2</sub>, and展开更多
基金supported by the National High Technology Research and Development Program of China (No 2006AA06Z113)the National Natural Science Foundation of China (No. 40772197)
文摘The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in China, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O (K1≥1.2). Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cu, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O (K2≥1.2). Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization: (a) Cu-Au mineralization; (b) W-Mo mineralization; and (c) silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows: Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as (Ag*Zn)D/(Mo×W)D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth.
基金National Doctoral Fund Project!(98024004)fund project of the L aboratoryofQuantitativePredictionExploration Assessment
文摘Grade-tonnage model is one of the research frontiers of systematical exploration theory. Based on the “Reserve Database of Mineral Resources in China (1997)”, this paper establishes the geological model, grade model, tonnage model, grade-tonnage model and tonnage-sequence model of contact metasomatic copper deposits in China. The mathematical properties of these models are described in detail.
文摘THE Kangdian region is a middle Proterozoic continental rift basin that extends between longitudes 101°30’and 103°20’. There are a series of sedimentary strata, named Xiaoqingshan Formation, Yinmin Forma- tion, and Luoxue Formation. The strata were metamorphosed and deformed in Jinning tectonic event between approximately 850 and 750 Ma. There are many lode-copper deposits in the Kangdian region. Xiaoqingshan is a typical one among of them. The orebodies of the deposit occurs in veins and the hostrocks of the deposit are sericite-phyllite and sericite-slate. The deposit is characterized by large-scale pervasive sodium metasomatism (PSM). It has been identified that albite replaced sericite and chlorite of the original rocks during the PSM.As a result, the pelites were transformed into albitolite, which consists of albite totally. Mass balancecalculations show that the PSM process involved addition of large amount of Na<sub>2</sub>O and SiO<sub>2</sub>, and