Petrology, geochemistry and geochronology of late Triassic volcanics, Kunlun orogenic belt, western China: Implications for tectonic setting and petrogenesis
文献类型：期刊论文
| 作者 | Liu, HT |
| 刊名 | GEOCHEMICAL JOURNAL
 |
| 出版日期 | 2005 |
| 卷号 | 39期号:1页码:1-20 |
| 关键词 | Calc-alkaline Volcanic Active Continental Margin Kunlun Orogen Western China |
| ISSN号 | 0016-7002 |
| 英文摘要 | The Qimantage volcanic suite (QVS) of late Triassic age, dominated by dacitic to rhyolitic lavas and pyroclastic rocks with minor basaltic andesites, outcrops mainly in the middle segment of Qimantage Mt. region, Kunlun orogenic belt, which extends along the northern margin of Tibetan plateau, western China. Petrological and geochemical studies indicate that the volcanic rocks are of typical calc-alkaline affinity with silica contents ranging from similar to 53 to similar to 80 wt%, exhibiting a medium- to high-K characteristics. Major element variations define relatively smooth compositional trends, while large ion lithophile (LIL) trace elements correlate positively with increasing SiO2. Chondrite-normalized incompatible trace element spidergram shows conspicuous sparks at Rb and Th, but pronounced Nb and Ti depletion. The chondrite-normalized REE patterns of QVS are generally paralleled to each other, exhibiting highly fractionated LREE/HREE spectra with small to pronounced negative Eu anomalies. Two whole-rock Rb-Sr isochrons yield ages of ca. 209 and ca. 225 Ma, respectively, indicating the volcanic suite was emplaced during the late Triassic. The initial Sr-87/Sr-86 ratios (0.708-0.709) and initial epsilon Nd(t) values (-2.05-2.35) imply that the magmas were derived from a slightly enriched mantle source with considerable crustal contamination. Considering its petrological, geochemical and isotopic characteristics in a regional geological background, it is proposed that QVS was generated upon an active continental margin during the late Triassic north-directed subduction event. Both the volcanics and the closely-related coeval granitoid plutons collectively make up the late Triassic arc magmatic belt on the palcogeographically southern margin of the Tarim continent. |
| 语种 | 英语 |
| WOS记录号 | WOS:000229681900001 |
| 出版者 | GEOCHEMICAL SOC JAPAN |
| 源URL | [http://ir.iggcas.ac.cn/handle/132A11/65600]  |
| 专题 | 中国科学院地质与地球物理研究所 |
| 通讯作者 | Liu, HT |
| 作者单位 | Chinese Acad Sci, Inst Geol & Geophys, Beijing 100029, Peoples R China |
| 推荐引用方式 GB/T 7714 | Liu, HT. Petrology, geochemistry and geochronology of late Triassic volcanics, Kunlun orogenic belt, western China: Implications for tectonic setting and petrogenesis[J]. GEOCHEMICAL JOURNAL,2005,39(1):1-20. |
| APA | Liu, HT.(2005).Petrology, geochemistry and geochronology of late Triassic volcanics, Kunlun orogenic belt, western China: Implications for tectonic setting and petrogenesis.GEOCHEMICAL JOURNAL,39(1),1-20. |
| MLA | Liu, HT."Petrology, geochemistry and geochronology of late Triassic volcanics, Kunlun orogenic belt, western China: Implications for tectonic setting and petrogenesis".GEOCHEMICAL JOURNAL 39.1(2005):1-20. |
入库方式： OAI收割
来源：地质与地球物理研究所
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