由气体水合物稳定存在的温度—压力条件，根据我国东海及其邻近海域的海底温度、地壳热流和地温梯度的分布，指出了该海区气体水合物可能的分布范围。主要在东海陆坡即冲绳海槽的西坡、冲绳海槽的东坡、和琉球海沟的西坡、琉球海沟和菲律宾海盆。分析指出，目前并不能肯定东海陆架区不存在气体水合物稳定存在的区域。由于冲绳海槽的热流值较高，特别是冲绳海槽的中部轴区，那里有较高的地温梯度，因而，海槽两坡的气体水合物主要分布在南部冲绳海槽。%The area of East China Sea and its vicinity includes East China Sea Shelf,Okinaw a Trough,Ryukyu Island,Ryukyu Trench and the west part of Philippine Sea.This is the famous zone of collision and subduction between an ocean block and a contin ental block.It is famous and attractive not only for its complex tectonic conten t but also for its abundant oil and gas resources.Since 1960s,the Institute of O ceanology,Chinese Academy of Sciences has conducted many geology and geophysics explorations in the area of East China Sea and its vicinity,such as seismic refl ection explorations,seisic refraction explorations,heatflow measurements,sea flo or temperature measurements and samplings.Recent years,scientists all over the w orld pay attention to the gas hydrate study in this area.This paper gives a brie f introduction to what is gas hydrate and its steady state under a given tempera ture-pressure condition.All the geological and geophysical data obtained in the explorations mentioned above has been carefully studied in the view of gas hydr ate.Based on this data,the pressure and temperature was calculated along a profi le which is perpendicular to the tectonic direction of Ryukyu T-A-Ba system do wn to several kilometers from the sea floor.Steady temperature-pressure conditi on of the gas hydrate is also analyzed along this profile.The paper points out t hat the possible areas that the gas hydrate can be steadily exit mainly are the west slope of the East China Sea,the west part of Okinawa Trough,the east slope of Ryukyu Trench and Philippine basin.The paper points out that it can not say t hat there are area in the East China Sea basin that the hydrate gas can steadily exist.
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