塔里木麻扎尔塔格基性岩墙群的侵位特征和空间分布规律研究  

Emplacement characteristics and spatial distribution of Permian Mazhartager basic dike swarms in Bachu area,Tarim basin.

作　　者：张自力[1] 秦其明[1] 田伟[2] 曹宝[1] 李百寿[1] 陈咪咪[2] 

机构地区：[1]北京大学遥感与地理信息系统研究所,北京100871 [2]北京大学地球与空间科学学院,造山带与地壳演化教育部重点实验室,北京100871

出　　处：《岩石学报》2008年第10期2273-2280,共8页Acta Petrologica Sinica

基　　金：科技部973项目(2007CB411307)资助

摘　　要：综合采用遥感和地质方法,研究了塔里木西北部麻扎尔塔格基性岩墙群的侵位特征和分布规律。在野外露头发现麻扎尔塔格地区三类岩浆岩的侵位顺序为花岗岩体→基性岩脉→正长斑岩脉;麻扎尔塔格岩体包括角闪正长岩、正长花岗岩和角闪石岩三种岩性岩石;并在岩体内部发现基性岩墙,这与前人认为岩体内部没有基性岩墙分布的认识不同。利用空间分辨率为0.61m和2.5m的高分辨率遥感影像,绘制了麻扎尔塔格地区遥感地质解译图。采用GIS方法对基性岩墙在岩体内部和围岩变质沉积岩中的岩墙分布特征进行统计分析,结果表明岩体内部的基性岩墙不具有沿两组共轭方向分布的特征,而是呈无优选方位的辐射状。上述发现和认识对于了解塔里木二叠纪大规模基性岩浆喷发的大地构造背景具有重要意义。Remote sensing technique and geological survey method are used to research the emplacement characteristics and spatial distribution of Permian basic dike swarms in the Mazhartager Mountain, northwestern Tarim Basin. Field outcrop observation shows the emplacement sequence of three types of igneous rocks is syenite intrnsion→hasic dikes→syenitic porphyritic dikes. Lithologically, the Mazhartager intrusion is composed by three types of rock, which are Hb-syenite, syenogranite and hornblendite. Many a basic dikes are found in Mazhatarger intrusion, which are different from previous observations. Remote sensing geological interpretation map was obtained by using GIS and high-resolution satellite data. Statistical analysis of basic dikes in syenite intrusion and country rocks had been done and results show that basic dikes are radicalized in Mazhartager intrusion and trend NNW in the country rocks. These discoveries may provide important information on geotectonic setting of Permain massive basic magma eruption in Tarim basin.

关 键 词：基性岩墙群 遥感 地质解译 麻扎尔塔格 塔里木 

分 类 号：P588.13[天文地球—岩石学]