| 青藏高原北部发现印支运动的新证据——来自同构造花岗细晶岩脉的响应 |
| |
| 引用本文： | 白国典,何凯,王艳慧,琚根社,杜保峰,王坤.青藏高原北部发现印支运动的新证据——来自同构造花岗细晶岩脉的响应[J].岩石矿物学杂志,2018,37(1):87-98. |
| |
| 作者姓名： | 白国典 何凯 王艳慧 琚根社 杜保峰 王坤 |
| |
| 作者单位： | 河南省地质调查院;河南省地质科学研究所; |
| |
| 基金项目： | 中国地质调查局区域地质调查项目（12120113033018） |
| |
| 摘 要： | 在青藏高原北部昆仑山口-甘德断裂与巴颜喀拉山中央断裂之间发育延伸超过100 km的呈雁列排列的花岗细晶岩脉带,这些花岗细晶岩脉走向多为北西向(118°),少量呈南北向(2°)。通过对其宏、微观特征分析研究,并结合在这两组花岗细晶岩脉中分别采获的224.7±0.64 Ma(南北向)与220.5±1.1 Ma(北西向)的锆石LA-ICP-MS U-Pb同位素年龄数据,指出这些花岗细晶岩脉是印支运动的产物,是早印支期可可西里-巴颜喀拉地块向东昆仑地块斜向俯冲过程中,岩浆沿着昆仑山口-甘德北西向冲掩断层下盘(南盘)形成的北西向与南北向两组"X"型共轭剪节理贯入形成的同构造花岗细晶岩脉。两组"X"型共轭剪节理的展布方向揭示了印支运动的主压应力方向,即NNW-SSE向;北西向雁列排列的节理反映其受右行走滑作用控制的特点;花岗细晶岩脉形成的最早时间(224.7±0.64 Ma)代表了这次俯冲走滑事件的时间,也即昆仑山口-甘德断裂的形成时间。
|
| 关 键 词： | 青藏高原北部 细晶花岗岩脉带 雁列 同构造 印支运动 |
| 收稿时间： | 2017/4/7 0:00:00 |
| 修稿时间： | 2017/12/4 0:00:00 |
New evidence of Indosinian movement in northern Tibetan Plateau: The response of the syntectonic granite aplite vein |
| |
| BAI Guo-dian,HE Kai,WANG Yan-hui,JU Gen-she,DU Bao-feng and WANG Kun.New evidence of Indosinian movement in northern Tibetan Plateau: The response of the syntectonic granite aplite vein[J].Acta Petrologica Et Mineralogica,2018,37(1):87-98. |
| |
| Authors: | BAI Guo-dian HE Kai WANG Yan-hui JU Gen-she DU Bao-feng and WANG Kun |
| |
| Institution: | Henan Institute of Geological Survey, Zhengzhou 450007, China,Henan Institute of Geological Survey, Zhengzhou 450007, China,Henan Institute of Geological Survey, Zhengzhou 450007, China,Henan Institute of Geological Sciences, Zhengzhou 450007, China,Henan Institute of Geological Survey, Zhengzhou 450007, China and Henan Institute of Geological Survey, Zhengzhou 450007, China |
| |
| Abstract: | The row echelon granite aplite veined belt extending over one hundred kilometers are developed between the Kunlun Mountain Pass-Gander fault and the Bayan Haran central fault in northern Tibetan Plateau, and most of them are NW-trending, with a few being SN-trending. Based on an analysis of the macroscopic and microscopic characteristics of the row echelon granite aplite veins, as well as the LA-ICP-MS zircon U-Pb dating data for the SN-trending(224.7±0.64 Ma) and NW-trending(220.5±1.1 Ma) granite aplite veins, it is considered that the granite aplite veins are the products of Indosinian Movement, and they were formed in the oblique subduction of the Hoh Xil-Bayan Har terrane beneath the East Kunlun terrane in early Indosinian. The syntectonic granite aplite veins were injected along the "X" conjugate shear joints in the NW(118°) and the SN(2°) direction in the footwall (south section) of the Kunlun Mountain Pass-Gander overthrust fault. The principal compressive stress direction is revealed by the distribution direction of two groups of "X" type conjugate shear joints, which is NW(118°) to the SN(2°). The left order row echelon joints suggest that they are controlled by dextral strike-slip. The earliest formation time of granite aplite veins(224.7±0.64 Ma)represents the time of subduction and strike-slip event, which is also the formation time of the Kunlun Mountain Pass-Gander fault. |
| |
| Keywords: | northern Tibetan Plateau granite aplite veins echelon joints syntectonic Indosinian Movement |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《岩石矿物学杂志》浏览原始摘要信息 |
| 点击此处可从《岩石矿物学杂志》下载免费的PDF全文 |
|
