Interpretation Of Gravity And Magnetic Anomalies In The South Yellow Sea And East China Sea

The South Yellow Sea and East China Sea are important prospective areas of oil and gas resources in east China sea.Compared with developed countries,China's Marine geological survey is at present at a low level.Marine geological survey is of great significance for China's land and resources survey,and magnetic and gravity data have important application value for Marine geological survey.Based on gravity and airborne magnetic data,collect the rock physical mechanics data in the study area,combining with the existing geological understanding and anomaly separation of gravity data interpolation cut from Moho discontinuity caused by abnormal geological structure,namely the residual gravity anomaly,the boundary identification for the residual gravity anomaly is calculated and derivative conversion,etc.,to obtain linear information structure in the study area.Due to the large span of latitude in the study area,The airborne magnetic data are processed by variable dip polarization to eliminate some false anomalies.The present efficient and stable continuation method is used to separate the anomalies,and analytical signal processing is carried out for the remaining anomalies.Based on the comprehensive processing results of gravity and magnetic data,the anomalies reflecting the distribution information of basin faults and igneous rocks in the study area are obtained.The rock physical mechanics data of the study area were studied and analyzed,and the main causes of gravity and magnetic anomalies were summarized.Based on the gravity and magnetic regional anomalies,the abnormal characteristics of the study area and the division of tectonic units were conducted,forming the regional tectonic framework of the study area.On the background of regional anomaly,and can be divided into several secondary local anomalies,not through the local magnetic anomalies morphological characteristics such as amplitude change,based on boundary identification results and the existing geological understanding,drew the outline of the fracture,the different levels in the study area are the general characteristics of fracture development in the study area,for some known fracture extension towards the new paint.Through local magnetic anomalies and its analytical signal processing,the main body of igneous rock distribution in the study area is determined,a total of 88,basically under the distribution characteristics of the igneous rock body in the study area combined with the existing geological understanding and the research achievements of predecessors,based on the magnetic regional anomalies and local anomalies,basin in the study area for the painting,concave boundary of basin is mainly carried on the detailed circle,at the same time within the sag on the main part has carried on the deep sag circle,basic in the south yellow sea and east China sea basin are the distribution of concave and convex shape size and other characteristics.