地球学报2025，Vol.46Issue(3)：519-532,14.DOI:10.3975/cagsb.2024.111302
羌塘盆地岩浆岩分布特征
Magmatic Rock Distribution in the Qiangtang Basin:Understanding from High-precision Airborne Gravity and Magnetic Survey
摘要
Abstract
Qiangtang Basin had experienced strong magmatic activities and many magmatic bodies are exposed on the surface.The magmatic activity reflects the tectonic evolution characteristics of the basin,and also plays an important role in the formation and preservation of oil and gas in the basin.Therefore,study of the magmatic rock characteristics of the basin provides a basis for understanding the tectonic evolution of the basin,and also facilitates investigation of oil,gas,and mineral resources in the basin.Based on high-precision airborne gravity and magnetic data from the Qiangtang Basin,this paper first uses airborne gravity and magnetic potential field conversion processing and other methods to achieve the scope of buried rock mass.Then,a large number of rock physical properties collected in the field were analyzed statistically,combined with geological and geochemical results,the typical airborne gravity and magnetic characteristics of the rock mass were summarized.The analysis showed that volcanic rocks,intermediate acid intrusive rocks and basic and ultrabasic rocks are the main factors causing local anomalies of the elevated positive and heavy magnetic fields in the region.Based on the connection between physical characteristics and geophysical field,magmatic rock mapping was carried out,and the distribution of basic-ultrabasic rock mass,acid-neutral rock mass and volcanic rock mass was established.The results showed that the Mesozoic intrusive rocks and Cenozoic volcanic rocks are very developed in and around the investigation area,which are the most important geological factors causing the changes of gravity and magnetic anomalies in this area.It is of great significance for oil and gas accumulation to identify a number of hidden intrusive rock bodies in the South Qiangtang Depression and Puruo Kangri and Gladandong areas in the North Qiangtang Depression.A large number of buried volcanic rocks have been identified in the eastern part of North Qiangtang Depression,and it is speculated that there may be low-density anomalous bodies in the deep part.The research results not only improve the understanding of the distribution characteristics of magmatic rocks,but also provide a reliable basis for the regional geological structure,basin evolution and oil and gas resources evaluation.关键词
羌塘盆地/隐伏岩体/航磁/航重/物性特征Key words
Qiangtang Basin/buried rock/aeromagnetic survey/airborne gravity survey/physical property analysis分类
地质学引用本文复制引用
魏岩岩,曹宝宝,周道卿,郑宇舟,胡夏炜,段宏伟,胡悦,肖梦楚,赵睿..羌塘盆地岩浆岩分布特征[J].地球学报,2025,46(3):519-532,14.基金项目
本文由自然资源部"航空地球物理与遥感地质重点实验室青年创新基金"(编号:2023YFL03)、中国地质调查局地质调查项目"西部重点油气调查区航空物探调查"(编号:DD20230319)和"重点地区航空地球物理调查"(编号:DD20230012)联合资助. This study was supported by Key Laboratory of Airborne Geophysics and Remote Sensing Geology Ministry of Natural Resources(No.2023YFL03),and China Geological Survey(Nos.DD20230319 and DD20230012). （编号:2023YFL03）
