Time filter

Source Type

Li G.,Nanjing University | Hua R.,Nanjing University | Zhang W.,Nanjing University | Hu D.,Nanjing University | And 5 more authors.
Resource Geology | Year: 2011

The Tieshanlong tungsten-polymetallic deposit is a large wolframite deposit of quartz vein type located in southern Jiangxi, South China. It is genetically related to a high-K S-type granite. Seven pyrite and two wolframite samples, selected for He and Ar isotope analyses, yielded 3He/4He values of 0.04-0.98 Ra, 40Ar/36Ar ratios of 293.5-368.0, and 38Ar/36Ar ratios of 0.176-0.193. These data indicate that the ore-forming fluids associated with the deposit did not result from a simple mixing of the crustal- and mantle-derived end-member fluids, but that primeval meteoric fluids were also involved in the generation of the associated granitic magma by partial melting of crustal metasedimentary rocks. Further investigations show that only minimal He from the mantle was added during generation of the associated granitic magma. It is postulated that boiling and second mixing with "new" meteoric fluids took place during migration of magmatic-hydrothermal fluids into wall-rock fractures, resulting in a drastic decrease of their metal transport capacity, which triggered the tungsten-polymetallic mineralization. © 2011 The Authors. Resource Geology © 2011 The Society of Resource Geology.

Li G.-L.,Nanjing University | Hua R.-M.,Nanjing University | Wei X.-L.,Jiangxi Bureau of Nonferrous Metal Exploration | Wang X.-D.,Nanjing University | And 2 more authors.
Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences | Year: 2011

The Xushan tungsten-copper deposit is located in the central part of Jiangxi Province. It is a trinity deposit comprising three types of ore-bodies, i.e. quartz vein type, skarn type, and granite type. Rb-Sr micro-isochron method is first applied to determining the ore-forming age by using single grain of muscovite growing at the edge of the wolframite-quartz vein type tungsten ore. Result shows that the mineralization age is 147.1±3.4 Ma, with MSWD=0.71, and the ISr value is 0.849±0.026. This ore-forming age is similar to those of quartz-wolframite-vein tungsten deposits in southern Jiangxi, but is much later than the ages of copper deposits in northeastern Jiangxi and slightly earlier than the ages of copper deposits in northwestern Jiangxi. The very high ISr value may suggest that the ore-related granite was a melting product of highly evolved and highly saturated crust material, and the ore-forming fluids have extracted the strontium of extremely high 87Sr/86Sr ratios from the granite through water-rock interaction. It also suggests that there was almost no contribution of mantle material during the formation of either ore-related granite or tungsten mineralization.

Li G.,Nanjing University | Hua R.,Nanjing University | Hu D.,Nanjing University | Huang X.,Jiangxi Bureau of Nonferrous Metal Exploration | And 2 more authors.
Acta Petrologica Sinica | Year: 2010

Shilei quartz diorite is one of the most special diorites in Chongyi-Shangyou-Dayu area, southern Jiangxi. Zircon U-Pb dating for one quartz diorite yields an emplacement age of 433.5 ± 3.4 Ma. Four samples are with middle contents of silica (SiO2 : 56.92% ∼ 64.70%), high contents of AL2O3 (14.10% ∼ 14.83%), Alk (6.41% ∼ 7.40%), K2O (3.86% ∼ 4.85%), MgO (3.47% ∼ 5.95%) and FeO (5.23% ∼ 8.14%) and low contents of P2O5 (0.27% ∼ 0.4%). They contain high contents of large ion lithophile elements such as K, Rb, Cs and light rare elements and low contents of high field strong elements such as Nb, Ta, Ti, P. Apatites are enriched in rare elements, their light rare elements contents are much higher than heavy rare elements contents. They have a low δEu (0.37 ∼ 0.45). The Sr-Nd isotope compositions are characterized by the follows: Distinctively middle initial Sr isotopic ratios (ISr= 0.7073 ∼ 0.7132): low initial Nd isotopic ratios (εNd(t) = -4.97 ∼ -8.41), two-stage model age ranging from 1.58Ga to 1.86Ga; zircon Hf isotopic analysis yields main εHf(t) values of - 8 to -2, with two-stage model age 1.77 ± 0.09Ga. These characters indicate that Shilei quartz-diorite is the product of an intensive interaction between crust and mantle. The lithosphere of this area perhaps once thinned in Late-Caledonian.

Loading Jiangxi Bureau of Nonferrous Metal Exploration collaborators
Loading Jiangxi Bureau of Nonferrous Metal Exploration collaborators