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The South China Sea, a part of the continental margin of western Pacific, has been attracting a great deal of attention of geoscientists for its special tectonic position and features. According to the theory of in-situ melting 'C intracrustal convection model (Chen and Grapes, 2007, Springer) this paper studies and summarizes the main geographical, geological and geophysical characteristics of the basin of the South China Sea and presents a model for the Cenozoic evolution of the continental margin of SE China, in which the tecto-geomorphologic evolution of the SE China continental margin in the Cenozoic is divided into three stages, namely the paleo-Cathaysian mountains stage running from the end of late Cretaceous to the early Paleogene, the peneplain stage in the late Paleogene and the marginal sea stage from Neogene to the present. The model outlines the process of the continental margin of SE China from the Andes type in Mesozoic to the western Pacific type in the late Cenozoic, and reveals the relationship of the temperature variations within the continental crust (lithosphere) of SE China and the tecto-geomorphologic evolution on the crustal surface. Cognitions arrived in this paper are mainly as follows: 1.Thinning of the upper crust in the SE China continental margin is mainly originated from the supra-crustal erosion; 2.High heat flow in the continental margin reflects predominantly the residual heat of the hot Mesozoic crust (lithosphere); 3.Both consolidation of the Mesozoic crustal melt layer and high gravity abnormity developed due to denudation of paleo-Cathaysian mountains lead to the gravitational adjustment of fault-brocks in continental margin of SE China in the late Cenozoic, resulting in formation of the marine basin of the South China Sea; 4.The normal-fault system in the South China Sea is the tectonic effect of the fault-block adjustment; 5.Formation of the island arcs and disaggregation of the Oligocene peneplain of SE China were originated from the material adjustment within the Mantle melt layer; 6.Under compression of the sinking fault-blocks part in the Mantle melt layer moves upwards along the opening normal faults, resulting in eruption of basic magma in Neogene.(reference number total 47)
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