摘要
海底电缆地震资料采集作为当前浅海及过渡带地区地震资料采集的主要方式,在滩海地震勘探中发挥了巨大作用。在渤海湾滩海地震资料采集作业中,形成的多样观测系统和灵活的变观作业技术,越来越多地被应用在常规拖缆不能作业的其他海上区域。在实际作业过程中,海况的复杂多变、海底地形的多样等,使得海底电缆作业经常在实施过程中遇到困难。通过海底电缆作业的介绍,重点对海沟发育区域如何确保放缆精度和二次定位精度、复杂障碍物区如何确保最佳品质地震资料、硬质海底地表和潮流活动较强条件下如何确保检波器与海底地表耦合这3种特殊情况进行了理论联系实际剖析,最后通过生产实例,对方法进行了验证和总结,提出了其他探区遇到类似问题时海底电缆施工难点的解决方法和现场作业质控建议。
OBC ( ocean bottom cable ) seismic survey as the primary method for seismic data acquisition in shallow water and transitional regions plays a significant role in tidal regions. OBC experiences involving diverse and flexible variable recording geometries in seismic survey in the tidal zones of the Bohai Bay have been frequently used in places where conventional streamers are not available. However, complicated marine conditions and varying ocean bottom topography often bring a lot of challenges to field OBC operation. This paper introduces OBC seismic survey by focusing on three special conditions: how to ensure the accuracy of cable layout and secondary positioning in ocean trenches, how to improve seismic data in complex obstacle area, and how to improve the coupling between geophones and seabed under the conditions of hard ocean bottom and stronger tidal activity. Cases are used to verify these conclusions and experience are summarized. Finally, this paper provides solutions and QC suggestions on OBC operation in similar survey areas.
出处
《中国石油勘探》
CAS
北大核心
2017年第6期112-117,共6页
China Petroleum Exploration
关键词
地震采集
海底电缆
放缆及二次定位
障碍物区
作业难点
检波器耦合
特殊观测系统设计
seismic acquisition, OBC, cable layout and secondary positioning, obstacle area, operation difficulty, coupling of geophones,special recording geometry design