河西走廊中东段基底岩相构造分析和大地构造单元划分

发布时间：2018-05-10 09:05

本文选题：航磁 + 基底　；参考：《地球物理学进展》2017年01期

【摘要】：河西走廊中东段地处青藏高原东北缘,是我国地震多发区和重要的铜镍、铀、多金属和油气等矿产地.通过对该区2013年度获取1∶5万高精度航磁资料进行数据处理和反演,推断了深断裂10条、大断裂33条,分析了基底起伏和岩相构造情况,重新对大地构造单元进行了划分.结果表明:不同构造单元之间航磁特征和基底岩相构造均存在明显差异.阿拉善地块(二级)呈弧形磁异常,基底岩相以沉积—变质和变质建造为主,断裂具弧形特征;北祁连弧盆系(二级)以负磁异常为背景,基底以火山建造和浅变质复理石建造为主,断裂可分为北西西向、北东向、北西向和近东西向四组.上述2个二级单元可细分为5个三级单元、16个四级单元和4个五级单元.这一研究结果为进一步研究青藏高原的隆升机制、研究区地震预测及矿产资源的找矿潜力评价提供了重要依据.
[Abstract]:The eastern section of the Hexi Corridor is located in the northeastern margin of the Qinghai-Xizang Plateau. It is an earthquake prone area and an important mineral area of copper, nickel, uranium, polymetallic and oil and gas in China. Based on the data processing and inversion of 11: 50,000 high precision aeromagnetic data obtained in this area in 2013, 10 deep faults and 33 large faults are inferred, the basement undulation and lithofacies structure are analyzed, and the tectonic units are reclassified. The results show that there are obvious differences in aeromagnetic characteristics and basement lithofacies among different tectonic units. The Alashan block (secondary) presents arc magnetic anomaly, the basement lithofacies is mainly sedimental-metamorphic and metamorphic, and the fault is arc shaped, and the North Qilian arc basin system (secondary) is set by negative magnetic anomaly. The basement consists mainly of volcanic formation and shallow metamorphic flysch formation, and the faults can be divided into four groups: NW, NE, NW and NW. The above two-level units can be subdivided into 5 three-level units, 16 4-4 units and 4 5-level units. The results provide an important basis for further study on uplift mechanism of Qinghai-Xizang Plateau, earthquake prediction and evaluation of prospecting potential of mineral resources in the study area.
【作者单位】：核工业航测遥感中心;中核集团铀资源地球物理勘查技术中心(重点实验室);
【基金】：甘肃省北祁连山—龙首山地区1:5万航空物探调查项目(中国地质调查局:12120114090501;中国核工业地质局:201215A)资助
【分类号】：P548;P631

【相似文献】