略阳白雀寺杂岩体以西隐伏深大断裂的推断依据及其意义  

The inferential basis and significance of the deep fault to the west of the Baiquesi complex in Lueyan

作　　者：游军 张小明 罗乾周 史朝洋 杨运军 陈剑祥 袁攀 YOU Jun;ZHANG Xiao-Ming;LOU Qian-Zhou;SHI Zhao-Yang;YANG Yun-Jun;CHEN Jian-Xiang;YUAN Pan(Shaanxi Center of Mineral Geological Survey,Xi’an 710068,China;Hanzhong Geological Party Co.,Ltd.,Shaanxi Bureau of Geology and Min-eral Exploration,Hanzhong 723000,China)

机构地区：[1]陕西省矿产地质调查中心,陕西西安710068 [2]陕西地矿汉中地质大队有限公司,陕西汉中723000

出　　处：《物探与化探》2021年第3期645-652,共8页Geophysical and Geochemical Exploration

基　　金：陕西省地质勘查基金项目(61202009347);陕西省公益性地质调查项目(202105、20180304)。

摘　　要：勉略宁地区是扬子板块周缘地质构造最为复杂的地区之一。通过对勉略宁西部白雀寺基性杂岩体以西的高磁异常带与区域重力异常梯度带及Fe、V、Ti等元素化探异常的对比研究,结合沿异常带分布的溢流相玄武岩的岩石地球化学特征,推测地表遥感解译出的NNE向浅层断裂深部可能存在规模更大的隐伏断裂。这一隐伏深大断裂可能为新元古代勉略宁地区弧后裂解背景下的幔源岩浆活动提供了重要通道:一方面由深成岩浆侵入形成白雀寺基性杂岩体与火成碳酸岩;另一方面,由裂隙式火山喷发形成带状展布的富含磁铁矿的溢流相玄武岩。这一隐伏深大断裂的推断对于勉略宁地区新元古代的地质构造背景与幔源岩浆成矿作用研究具有重要意义。Mianluening area is one of the most complex areas of geological structure around the Yangtze plate. Based on the comparative study of the high magnetic anomaly zone to the west of Baiquesi basic complex, the regional gravity anomaly gradient zone and the geochemical anomalies of Fe, V, Ti and other elements, combined with the geochemical characteristics of the overflow phase basalts distributed along the anomaly zone, it is inferred that there may be a larger hidden fault in the deep part of the NNE-trending shallow faults interpreted by surface remote sensing. This hidden deep fault may have provide an important channel for the mantle-derived magmatic activity in the context of post arc cracking in Mianluening area in the Neoproterozoic. On the one hand, the Baiquesi basic complex and igneous carbonatite were formed by the intrusion of the plutonic magma;on the other hand, the belt like overflow phase basalt rich in magnetite was formed by the fissure type volcanic eruption. This finding is of great significance for the study of Neoproterozoic tectonic setting and mantle-derived magmatic mineralization in Mianluening area.

关 键 词：重力 地面高精度磁测 岩石地球化学 隐伏深大断裂 白雀寺杂岩体 

分 类 号：P631[天文地球—地质矿产勘探]