THE MAGNETIC ANOMALY PATTERN IN THE EASTERN CHINA SEAS AND ITS GEOLOGICAL INTERPRETATION

A new round of magnetic anomaly map of eastern China seas and adjacent areas has been compiled with advanced computer means based on the new magnetic data and former researches. Generally, the intensity of magnetic anomalies varies around ±200 nT, except for some local ones, which may reach values over ±500 nT. The anomalies extend in NE or NNE direction in a banded pattern. The types and distribution pattern of local anomalies are variable. However, they all show a banded pattern in EW direction and blocky pattern in NS direction in general, owing to the control of tectonics.. According to the amplitude, shape, and distribution pattern of the magnetic anomalies, the magnetic anomaly map is divided into nine regions, such as the North China-Bohai magnetic anomaly region and Shandong peninsula-north Yellow Sea anomaly region, etc. and 34 subregions. The geological implication of the distribution pattern is discussed in details in this paper.