摘要
琼东南盆地资源潜力巨大,水合物成藏条件优越,是天然气水合物的有利探区。为更好地研究天然气水合物的赋存情况和展布形态,在成藏背景分析的基础上,对琼东南盆地北部探区重点区块的三维地震资料进行了波阻抗反演,依据水合物储层的波阻抗差异,精确刻画出天然气水合物矿藏的空间展布形态并计算其厚度和物性参数。结果表明,研究区重点矿体波阻抗高低分异明显,地质现象清晰。天然气水合物储层表现为高波阻抗特征,波阻抗值为31005500(m/s)×(g/cm^(3));气态烃储层表现为低波阻抗特征,波阻抗值小于2900(m/s)×(g/cm^(3))。天然气水合物与气态烃集中分布在矿体A和矿体B上,矿体A和矿体B中水合物厚度为15~50m,平均饱和度为10%~40%;矿体A气态烃厚度为30~100m,平均含气饱和度为15%~30%;矿体B气态烃厚度较小,饱和度也相对较低。研究区的钻井资料很好地验证了预测结果,海底隆起带是水合物矿藏勘探的有利区。
Qiongdongnan Basin is a favorable exploration area for natural gas hydrate due to its great resource poten-tial and superior hydrate accumulation conditions.To better study the distribution and occurrence of natural gas hydrate,the wave impedance inversion is carried out on the key blocks of the 3D seismic data in the northern explo-ration area of the Qiongdongnan Basin on the basis of the accumulation background analysis.And according to the wave impedance difference of hydrate reservoir,the spatial distribution form of gas hydrate deposits is accurately characterized and its thickness and physical property parameters are calculated.The results indicate that the key ore bodies in the study area exhibit obvious differentiation contrast in seismic dependence and the geological features are clear.The natural gas hydrate reservoirs are characterized by high wave impedance with values ranging from 3100 to 5500(m/s)×(g/cm^(3)):Gaseous hydrocarbons reservoirs are characterized by low wave impedance,with wave impedance values less than 2900(m/s)×(g/cm^(3)).Natural gas hydrate and gaseous hydrocarbon are concen-trated in ore body A and ore body B,with hydrate thickness ranging from 15 to 50 meters,and average saturation of 10%to 40%;The thickness of gaseous hydrocarbon in ore body A is from 30 to 100 meters,and the average gas saturation is between 15%to 30%;The thickness of gaseous hydrocarbon in ore body B is small,and the saturation is relatively low.The drilling data in the study area well verified the prediction results,the submarine uplift zone is a favorable area for hydrate exploration.
作者
路允乾
孟大江
文鹏飞
张宝金
LU Yunqian;MENG Dajiang;WEN Pengfei;ZHANG Baojin(Gruangzhou Marine Geological Survey,Guangzhou 510075,China;Southern Marine Science and Engineering Guangdong Laboratory(Guang zhou),Guang zhou 511458,China;Gas Hydrate Engineering Technology Center,Guangzhou 510075,China)
出处
《非常规油气》
2023年第6期18-26,共9页
Unconventional Oil & Gas
基金
中国地质调查局项目“南海重点海域天然气水合物调查评价项目”(DD20221705)
广东省海洋经济发展(海洋六大产业)专项资金项目“南海珠江口盆地油气与水合物共生系统特征与评价技术”(粤自然资合[2021]58号)
南方海洋科学与工程广东省实验室(广州)人才团队引进重大专项“南海深海盆区莫霍面地震反射空间分布研究”(GML2019ZD0207)。
关键词
天然气水合物
储层反演
饱和度预测
琼东南盆地
natural gas hydrate
reservoir inversion
saturation prediction
Qiongdongnan Basin
