Abstract: On the basis of the latest shipboard magnetic data merging with the world digital magnetic anomaly, we have calculated the reduction to the pole (RTP) anomaly, pseudogravity anomaly, analytic signal and tilt angle, and used the wavelet decomposition and frequency spectrum analysis for the RTP anomaly. The results revealed the magnetic signature of the main tectonics in eastern China and adjacent sea. The distributions of paleocontinental nucleus in the North China block were indicated as well as the boundaries of Yangzi block. It was pointed out that the volcanic belt in the coastal area of Zhejiang and Fujian provinces connects to the Dongsha Uplift, and both of them are Mesozoic subduction volcanic arc. The NWoriented fault may be the boundary fault in which PaleoTethys tectonic domain converted to the Pacific tectonic domain, and controlled the subduction process during the Late Mesozoic and the conversion from the active continental margin to the passive continental margin since the Mesozoic at the Northern South China Sea continental margin.

Key words: eastern China and adjacent sea, magnetic anomaly, data merging, tectonic significance