The application of post-stack impedance inversion without well to the prediction of gas hydrate distribution in T study area
WAN Xiao-Ming1,2, LIANG Jing1,2, LIANG Jin-Qiang1,2, LIN Lin1,2, SHA Zhi-Bin1,2, CHAI Yi1,2, CAI Zhen-Hua3
1. Key Laboratory of Marine Mineral Resources of Ministry of Land and Resources, Guangzhou 510760, China;
2. Guangzhou Marine Geological Survey, Guangzhou 510760, China;
3. Drilling Division, CNPC Offshore Engineering Co., Ltd, Tianjin 300280, China
Aimed at investigating the geological conditions and the modes of occurrence of gas hydrate on the northern slope of South China Sea, the authors established a three-dimensional interval velocity model based on the three-dimensional seismic data and stacking velocity spectrum under the condition of lack of logging data, and then transformed the data to low impedance background model. Subsequently, the authors extracted pseudo wells and tied them accurately, and finally obtained an absolute impedance and fine velocity bodies by the constrained sparse spike inversion method. Meanwhile, the authors comprehensively utilized seismic and inversion data,analyzed the best threshold value for distinguishing the gas hydrate in the study area and, on such a basis, quantitatively interpreted the gas hydrate. The results obtained show that:First,the velocity of gas hydrate is about 2050~2150 m/s, and P-impedance is above 3.9×106 kg·m-3·m·s-1 in the study area,which are higher than the velocity and impedance of surrounding rock;Second,the distribution of gas hydrate is extensive, especially in the middle west and southeast region,where the preliminary estimated maximum thickness is up to 48m.
万晓明, 梁劲, 梁金强, 林霖, 沙志彬, 柴祎, 蔡振华. 叠后波阻抗无井反演技术在T研究区天然气水合物分布预测中的应用[J]. 物探与化探, 2016, 40(3): 438-444.
WAN Xiao-Ming, LIANG Jing, LIANG Jin-Qiang, LIN Lin, SHA Zhi-Bin, CHAI Yi, CAI Zhen-Hua. The application of post-stack impedance inversion without well to the prediction of gas hydrate distribution in T study area. Geophysical and Geochemical Exploration, 2016, 40(3): 438-444.
[1] Kvenvolden K A.Gas hydrates-geological perspective and global change[J].Rev.Geophys,1993, 31(2): 173-187.
[2] 马在田,宋海斌,孙建国.海洋天然气水合物的地球物理高新探测技术[J].地球物理学进展,2000,15(3):1-6.
[3] 宋海滨,张岭,江为为,等.天然气水合物的地球物理研究(III):似海底反射.地球物理学进展[J].2003,18(2):182-186.
[4] 杨睿,吴能友,雷新华,等.波阻抗反演在南海北部神狐海域天然气水合物勘探中的应用[J].现代地质,2010,24(3):496-500.
[5] 徐华宁,梁蓓雯,张光学,等.南海北部陆坡天然气水合物地震识别研究[J].天然气工业,2006,26(9):49-51.
[6] 牛滨华,文鹏飞,温宁,等.基于BSR的AVO正演估算水合物含量方法的研究[J].地球物理学报,2006,49(1):143-151.
[7] 姚伯初.南海北部陆缘天然气水合物初探.海洋地质与第四纪地质[J].1998,18(4):11-18.
[8] 王秀娟,吴时国,刘学伟,等.东沙海域天然气水合物特征分析及饱和度估算[J].石油物探,2009,48(5):445-451.
[9] 宋海滨,耿建华,Wang H K,等.南海北部东沙海域天然气水合物的初步研究[J].地球物理学报,2001,44(5):687-693.
[10] 李梅,郗诚,张志让,等.虚拟井约束地震反演方法在台地斜坡带鲕滩储层预测中的应用——以四川盆地龙岗地区某单元为例[J].海相油气地质,2012,17(4):73-77.
[11] 沙志彬,郑涛,杨木壮,等.基于波阻抗反演的天然气水合物地震检测技术[J].现代地质,2010,24(3) :481-487.
[12] 辉固地球科学(北京)有限公司[R].培训资料.2012.
[13] 梁劲,王宏斌,梁金强.Jason反演技术在天然气水合物速度分析中的应用[J].南海地质研究,2006:114-120.
[14] 梁劲,王明君,陆敬安,等.南海北部神狐海域天然气水合物沉积层的速度特征[J].天然气工业,2013,33(7) :29-33.
[15] 张光学,祝有海,梁金强,等.构造控制型天然气水合物矿藏及其特征[J].现代地质, 2006, 20 (4): 605-612.
[16] Zhang G X,Yang S X,Zhang M,et al.GMGS2 investigates a rich and complex gas hydrate environment in the South China Sea [J].Fire in the ice, 2014, 1-5.