南海北部天然气水合物赋存带识别与深度预测

IDENTIFICATION OF GAS HYDRATE RESERVOIR AND ITS DEPTH ESTIMATION IN SHENHU AREA, SOUTH CHINA SEA

摘要: 利用地球物理方法,在钻探前对水合物赋存带进行识别和深度预测,可以为钻探井位的选取及井深的规划提供直接的数据支持。在我国南海北部二维地震数据的基础上,以速度为主要判别依据,以波阻抗反演为佐证,识别水合物赋存带的顶、底界,并以叠加速度谱为基础,预测神狐海域A测线预测井位的水合物赋存深度。在此数据的指导下,经钻探证实,该钻位在预测深度附近确实存在高饱和度的水合物矿藏。

Abstract: Rationale drilling planning requires precise data on gas hydrate reservoir and its depth before drilling. 2-D seismic data from the Northern South China Sea were used to identify the top and bottom of the gas hydrate reservoir by the changes in velocity and impedance. The depth of the reservoir was then calculated with RMS velocity. Guangzhou Marine Geological Survey carried out field drilling in 2007, and the gas hydrate reservoir with high saturation was discovered at the depth predicted, suggesting that the calculation is precise enough for drilling planning.