南黄海航空重力局部异常解析

Interpretation of local anomalies of airborne gravity in the South Yellow Sea

在南黄海海域航空重力测量的基础上进行了重力场分区,研究了重力场分区与区域地质环境的内在联系,探讨了形成局部异常的主要地质因素.采用有效的提取方法对局部异常进行了筛选和提取,并按成因划分为基岩局部凸起类异常、基岩局部凹陷类异常、侵入岩类异常、火山岩类异常.通过对典型剖面进行重磁联合反演,细化了各类异常的特征并分析引起异常的地质成因,认为基岩局部凸起类异常、基岩局部凹陷类异常、岩浆岩类异常是南黄海海域具有找油意义的重点局部异常.通过对局部异常进行处理与解释,尝试利用重力异常研究南黄海海域油气成藏的可能性.

On the basis of airborne gravimetry in the South Yellow Sea, this paper divides gravity field into three regions. Through studing haternal relationships between gravity field division and regional geologic media, we discuss major geological factors which formed local anomalies. In the study area, We explore effective methods to extract local anomalies, then classify them as four classes according to the geological factors, which include anomalies of basement salients, basement sags, intrusive rocks, volcanic rocks. Using joint inverse of airborne gravity and magnetic profile, we discribe the characteristics of each type of anomalies, then analyse the factors caused anomalies. The results indicate that anomalies of basement salients, basement sags and magmatic rocks are the important prospecting anomalies which have significance to oil and gas exploration in the South Yellow Sea. Based on local anomalies processing and geological interpretation, we attend to study the possibility of hydrocarbon reservoir in the South Yellow Sea using airborne gravity anomalies.