电火花震源高分辨率地震勘探技术及其在海域天然气水合物识别中的应用  

High-resolution seismic exploration technology with spark source and its application in identification of natural gas hydrates in marine areas

作　　者：骆迪[1,2] 蔡峰 闫桂京[1,2] 李清 孙运宝[1,2] 董刚 李昂[1,2] LUO Di;CAI Feng;YAN Guijing;LI Qing;SUN Yunbao;DONG Gang;LI Ang(The Key Laboratory of Gas Hydrate,Ministry of Land and Resources,Qingdao Institute of Marine Geology,Qingdao 266237,China;Laboratory for Marine Mineral Resources,Qingdao Marine Science and Technology Center,Qingdao 266237,China)

机构地区：[1]青岛海洋地质研究所自然资源部天然气水合物重点实验室,青岛266237 [2]青岛海洋科技中心海洋矿产资源评价与探测技术功能实验室,青岛266237

出　　处：《海洋地质与第四纪地质》2024年第6期34-45,共12页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金“南海北部高富集天然气水合物储层特征与成藏控制机理研究”(U2244224),“马克兰增生楔低角度俯冲区断层‘接力’过程及其对水合物成藏的控制”(42076069)。

摘　　要：精准识别天然气水合物对于保障国家能源安全、优化能源结构和环境保护等方面都具有重要的战略意义。地震勘探技术是水合物勘查的重要手段,但海域多道地震勘探多采用气枪震源,震源主频较低,导致地震波的分辨率有限,限制了其在探测浅表层或细微地质结构中的能力。随着水合物勘查精度和难度日益增长,采用气枪震源的地震勘探技术已无法满足精细刻画水合物矿体的需要。因此,提高地震勘探技术的分辨率对于水合物勘查而言至关重要。本文介绍了一种基于电火花震源的小道距高分辨率地震探测技术,通过与气枪震源的对比分析,深入探讨了电火花震源的特点及其在海域水合物勘查中的应用,研究结果表明,电火花震源地震勘探技术在扩散型水合物和浅表层渗漏型水合物识别中都具有良好的应用效果,尤其是对于浅表层渗漏型水合物,电火花震源地震可以更好地识别出海底和浅部地层的振幅异常、流体运移通道和海底微地貌,可有效提高浅表层渗漏型水合物识别的可靠性。Accurate identification of natural gas hydrates is of great strategic importance for ensuring national energy security,optimizing energy structures,and protecting the environment.Seismic exploration technology is a crucial means for hydrate exploration.However,most multi-channel seismic explorations in marine areas use airgun sources with relatively low dominant frequencies,resulting in limited resolution of seismic waves,which limits its ability to detect shallow surface layers or subtle geological structures.With the increasing in demand for accuracy and the difficulty of hydrate exploration,seismic exploration technology using airgun sources can no longer meet the needs of fine characterization of hydrate ore bodies.Therefore,improving the resolution of seismic exploration technology is crucial for hydrate exploration.This paper introduces a high-resolution seismic detection technology based on small-offset electric sparker sources.Through comparative analysis with airgun sources,the characteristics of electric sparker sources and their application in marine hydrate exploration are deeply discussed.Results show that high-resolution seismic exploration technology using electric sparker sources has good application effects in identifying both diffused hydrates and shallow leakage hydrates.Especially for shallow leakage hydrates,using electric sparker source seismology can better identify amplitude anomalies,fluid migration pathways,and subtle seabed morphologies in the seabed and shallow strata,which can improve effectively the reliability of identifying shallow gas hydrate.

关 键 词：高分辨率地震 电火花震源 天然气水合物 地震属性 

分 类 号：P631.4[天文地球—地质矿产勘探] P736[天文地球—地质学]