南黄海崂山隆起地震采集参数设计  

Seismic acquisition design for Laoshan uplift of the South Yellow Sea

作　　者：张异彪 李玉剑 陈建文[3] 李斌 刘璐晨 黄涛 施剑[3] 刘俊[3] ZHANG Yibiao1 ,LI Yujian1,2, CHEN Jianwen3 , LI Bin1 ,LIU Luchen1 ,HUANG Tiao1,2,SHI Jian3 ,LIU Jun3(1 . Shanghai Geophysical Branch of Sinopec Offshore Oilfield Services Company,Shanghai 201208, China; 2. School of Ocean and Earth Science, Tongji University, Shanghai 200092, China; 3. Qingdao Institute of Marine Geology, China Geological Survey, Qingdao 266071, Chin)

机构地区：[1]中石化海洋石油工程有限公司上海物探分公司,上海201208 [2]同济大学海洋与地球科学学院,上海200092 [3]中国地质调查局青岛海洋地质研究所,青岛266071

出　　处：《海洋地质与第四纪地质》2018年第3期143-151,共9页Marine Geology & Quaternary Geology

基　　金："南黄海油气资源调查"(DD20160512);"南黄海海域油气资源普查"(GZH20080503);"南黄海前第三系油气前景研究"(XQ-2005-01)

摘　　要：南黄海崂山隆起中-古生界海相碳酸盐岩沉积层是重要的油气勘探目的层,但因工区水深较浅,新生界陆相地层与中生界海相地层之间存在强波阻抗界面,中-古生界碳酸盐岩地层结构较为均匀、速度和密度梯度较小、厚度较大等原因,造成中-古生界地震有效反射波存在能量弱、信噪比低等问题。针对如何增强中-古生界有效反射波能量、提高其信噪比展开采集参数设计。在大量设计方案的基础上,优选出2组强能量、富低频的容量为6390in3的平面组合和立体组合气枪震源;设计接收缆长度7200m,优选接收缆沉放深度16m和20m。对气枪震源和接收缆沉放深度组成的4组试验方案进行外业采集并分析,确定低频能量更强的6390in3平面震源沉放10m、接收缆沉放16m作为地震采集方案,并在空间采样间隔和工区施工环境分析等基础上提出了适合现阶段南黄海崂山隆起中-古生界地震勘探的单源6缆采集方式和采集参数,形成了高覆盖、富低频、强能量地震采集技术。与以往地震资料进行了对比,本次采集的地震资料中-古生界地层反射能量更强,信噪比更高,整体提高了中-古生界地震资料的品质,为后续南黄海地震勘探积累了经验,为下一步井位论证等工作奠定了扎实的基础。The Mesozoic-Paleozoic marine carbonate deposits on the Laoshan uplift of South Yellow Sea are critically important for petroleum exploration.However,the seismic reflection of the Mesozoic-Paleozoic strata has the problems of weak energy and low S/N ratio,owing to the facts that water is relatively shallow,the interface between the terrestrial Cenozoic and the marine Mesozoic is too strong as a seismic impedance reflector,the structure of Mesozoic-Paleozoic strata is uniform with little velocity and density difference,and the thickness of Mesozoic-Paleozoic strata is too large.In the seismic survey of the project,measures were taken to enhance the seismic reflection wave’s energy and increase the S/N ratio of the Mesozoic-Paleozoic strata,with specific design on both seismic source and acquisition parameters.A6390 in 3 air gun source with strong energy and low frequency,and with both single level mode and multi-level mode was designed.Two streamer depth candidates（16 m and 20 m）were chosen.The streamer length was designed to be 7200 m.4 acquisition tests were conducted and the 6390 in 3 in single level mode with depth of 10 m and streamer depth of 16 m were settled as the final acquisition parameters.A single source-6 steamer is used to increase the spatial sampling.All these formed a seismic acquisition design with high folds,rich low frequency and strong energy.Compared to the previous seismic data,the seismic data of this survey had an overall improvement in quality for the Mesozoic-Paleozoic strata,as the seismic reflection energy of the Mesozoic-Paleozoic was enhanced and the S/N ratio increased.The breakthrough in seismic data quality will lay a solid foundation for the next drilling site determination.

关 键 词：气枪震源设计 富低频 高信噪比 崂山隆起 中-古生界 

分 类 号：P738[天文地球—海洋地质]