marginal sea
2.STUDYING THE STRUCTURE OF CRUST AND UPPER MANTLE IN EAST ASIA AND WEST PACIFIC MARGINAL SEA BY RAYLEIGH SURFACE WAVE
3.Temperature increased 2-3 °C in some regions of the Arctic continents. Coverage of sea ice decreased 5% in the Arctic Ocean, thickness of sea ice shrunk in the center of the Arctic Ocean, the surface and intermediate water layers are freshening and warming, absorption of the atmospheric CO 2 increased in the marginal sea ice zone, and depletion of ozone appeared and ultraviolet radiation increased.
4.On the basis of geological survey of the scale of 1 : 50000 in Xinjiazhuang and Honghuapu sheet in Fengxian area in the west sect of the north Qinling orogenic belt and of achievement of former reserchers, and of comparison of the rock type, petrochemistry, geochemistry of the Danfeng Group, Caotangou Group, author thinks that they belong to calcalkali series, Danfeng Group is the combination of intermediate rock-basic rock, showing the background of island arc-marginal sea; Caotangou Group is the combination of intermediate rock-acid rock, showing the background of move of rift valley of basin after island arc.
6.This paper presents the petroleum expiration history and geologic research results in marginal basins of northern South China Sea, and based on the abundant geologic, geophysical and geochemical data, analyzes and summarizes the different basinal geologic features, the regional structural background for oil-gas migration and accumulation and the exploratory potentials or targets in this area.
