Yao L.,Development and Research Center |
Yao L.,China University of Geosciences |
Yao L.,REPUBLIC RESOURCES |
Lu Z.,Development and Research Center |
And 10 more authors.
Acta Petrologica Sinica | Year: 2015
The Qimantag area of Qinghai Province (hereafter referred to as QAQP), located within western part of East Kunlun orogenic belt, is one of the most important prospecting regions of China. In this study, we present new mineralogical data for granitic rocks associated with No. I section (Fe) of the Hutouya deposit (HD-I), Yemaquan Fe deposit (YD), No. B section (Cu) of the Kaerqueka deposit (KD-B) and No. VI section (Zn) of the Hutouya deposit (HD-VI) within the QAQP. Plagioclases of granitic rocks from the HD-I, HD-VI, YD and KD-B mainly belong to oligoclase (An15.0-24.1), albite and oligoclase (An8.7-20.8), oligoclase and andesine (An26.2-48.4), and andesine (An33.8-42.2), respectively. The hornblendes from the HD-I and KD-B mainly belong to ferro-edenite, and magnesiohornblende and ferrohornblende, respectively. The biotites are Fe-rich annite, and have high Ti, F and CI concentrations. Mineral characteristics show that biotites in these rocks formed under similar oxygen fugacities, but have different temperatures of crystallization and magmatic fluid compositions. The crystallization temperatures and oxygen fugacities of these biotites do not show any associations with skarn types. According to the results of previous studies, we argue that the crystallization temperatures and oxygen fugacities of these biotites are not important factors in controlling skarn types in the QAQP. Biotite compositions show that the magmatic fluids associated with the KD-B (Cu) are characterized by high CI, H2O and low F fugacities; the magmatic fluids of the HD-VI (Zn) have high F, low H2O and CI fugacities; the magmatic fluids associated with the HD-I and YD (Fe) show characteristics of high CI and low H2O and F fugacities. This indicates that volatile compositions of magmatic fluids are associated with skarn types. Geological and mineralogical evidences indicate that volatile compositions of magmatic fluids play a key role in controlling the mineralization diversity within the QAQP.
Feng C.Y.,Chinese Academy of Geological Sciences |
Wang S.,China Coal Technology and Engineering Co. |
Li G.C.,Chinese Academy of Geological Sciences |
Ma S.C.,Chinese Academy of Geological Sciences |
Li D.S.,Third Institution of Qinghai Geological Mineral Prospecting
Acta Petrologica Sinica | Year: 2012
The Qimantage area, located on the southwestern margin of Qaidam Basin, is not only a characteristic intrusive magmatic tectonic belt, but also a very important poly-metallic metallogenic belt. In this paper, detailed geochronological, element geochemical, Sr-Nd-Pb isolopic studies were carried out for the Middle to Late Triassic granitoids, and relationship between granitoids and poly-metallic mineralization was discussed. The Middle to Late Triassic granitoids in Qimantage area are characterized by the metaluminous to peraluminous and high-K calc-alkaline rocks. Of them, the Late Triassic granitoids is much enriched in K2O/Na2O ratio, LILE and LREE, and poor in HESE. The rocks exhibit moderate initial 87Sr/ 86Sr values and comparatively negative εnd(t) values, which indicate that they were derived from ancient crust sources and mixed probably by mande material. The precise U-Pb zircon dating results define emplacement of the mianthite-riched granodiorite occurred during 230 ∼ 237Ma, Late Triassic porphyritic granitiods intruded at 228 ∼ 204Ma. It is inferred that the tectonic transformation from crustal compression to extension was produced at about 240Ma, and was accompanied by mantle source magmatism. The occurrence of Late Triassic high differentiated and high-K calc-alkaline granitoids indicates that this area had evolved into post-collisional environment. The large numbers of porphyry and skarn-type poly-metallic deposits are temporally and spatially related to Middle to Late Triassic granitic intrusions.
Feng C.-Y.,Peking University |
Feng C.-Y.,Chinese Academy of Geological Sciences |
Li D.-S.,Third Institution of Qinghai Geological Mineral Prospecting |
Wu Z.-S.,Bureau of Mineral Resources |
And 5 more authors.
Northwestern Geology | Year: 2010
Based on some fieldwork and geochemical analyses in recent years, the metallogenic setting, major types, basic geological characteristics, time-space distribution and metallogeneses of polymetallic deposits (occurrences) in the Qimantage metallogenic belt, Eastern Kunlun area are described briefly in this paper. The ore-forming elements are comprehensive and dominated by Fe, Cu, Pb, Zn, Mo, W, Sn and Au. Several various styles of polymetallic mineralization in the Qimantage metallogenic belt have been recognized and Clasified into the skarn-type deposit, porphyry deposit, hydrothermal superimposed stratabound deposit and hypothermal deposit. Two important mineralization ages of both Middle-Late Triassic and early Paleozoic for polymetallic deposits are determined in the belt. For Middle to Late Triassic porphyry and skarn-type deposits, the ore-forming materials were mainly derived from magmatic and carbonate-bearing strata, and ore-forming fluids came chiefly from magmatic fluids; and both of them belong to products of the same tectonomagmatic cycle of Triassic period, although they formed in different stage, different depth and different place.
Li H.,Qinghai Geological Survey |
Yang Q.-A.,Fifth Institution of Qinghai Geological Mineral Prospecting |
Zhang D.-M.,Third Institution of Qinghai Geological Mineral Prospecting |
Li H.-H.,Third Institution of Qinghai Geological Mineral Prospecting |
And 2 more authors.
Journal of Chengdu University of Technology (Science and Technology Edition) | Year: 2015
The paper discusses the prospecting methods and potential of the gold deposits in the Manzhanggang area, Qinghai, China. Based on the geological background of the regional metallogenic geological conditions, the geochemical characteristics of stream sediments and soils, and the engineering verification, the paper analyzes the distribution of the abnormal elements such as Au, Sb, Bi, Zn, Hg and W and their concentration regularity. The results show that the metallogenic geological conditions are good and the geochemical anomalies are widespread in this area. The exploration work proves that the geochemical anomaly is the indicator to search for gold deposits. There is a huge potential of gold fields resources in the Manzhanggang area. The previous exploration demonstrates that the effective exploration method is the combination of geology, geochemical test, stream sediment test, soil test and engineering verification.