Effectiveness Of Geochemical Prospecting Methods Of Gas Hydrate In South China Sea

Gas hydrate is recognized as the biggest new energy undeveloped on the earth. It lit up the hope light of new energy for people in the 21st century. Also, it is regarded as the most promising new strategic resource, and to take over the petroleum oil. China is the second largest energy consumption country all around the world. Reducing the energy use and looking for a new alternative energy have become inevitable when we facing the shortages of petroleum resources. It is very important for us to strengthen basic research and explore the gas hydrate resource in South China Sea.Based on the topic of potential area of gas hydrate in South China Sea, this dissertation includes two parts: indicators and application. In the first part, the geochemical exploration indicators of gas hydrate used in ODP and South China Sea exploration are summarized. And the reliability of the method of hydrocarbon acid is discussed. In the second part, Xisha Trough and Qiongdongnan Basin are selected as the experimental area; the method of hydrocarbon acid is used for the geochemical exploration of gas hydrate resources. The work of this paper included:1. Geochemical exploration indicators of gas hydrate used in Ocean Drilling Program and South China Sea exploration are summarized in detail.2. Assist to complete hydrocarbon acid test of sixty-seven samples in the lab of Geology Institute. With the data of ODP164 and ODP204 as reference, the method of hydrocarbon acid is proved to be feasible and can be used in the preliminary exploration stage.3. All the hydrocarbon test data about South China Sea in our laboratory are sorted. After analysis, we get that the high value areas of methane mainly distribute in the North Slope zone and methane is mainly pyrolytic, but some mixed with a little biological caused gas. Combined with the data collected from other scholars and data tested by ourselves with hydrocarbon acid method, scatter plot ofδ13C1、C1/(C2+C3) for part of South China Sea is painted.The hydrate system of Xisha Trough and Qiongdongnan Basin are discussed, gas hydrate in Xisha Trough is leakage-diffusion model and hydrate in Qiongdongnan is leakage model. The most potential area of gas hydrate is Qiongdongnan Basin.