杨富东^1,2,4,,
张佳政^1,2,,,
杜峰³,
王强^1,2,4,
庞新明^1,2,4,
赵明辉^1,2,4,
丘学林^1,2,4
1. 中国科学院边缘海与大洋地质重点实验室, 南海海洋研究所, 广州 510301
2. 中国科学院南海生态环境工程创新研究院, 广州 510301
3. 湖北省地震局, 地震预警湖北省重点实验室, 武汉 430071
4. 中国科学院大学, 地球与行星科学学院, 北京 100049

基金项目: 国家自然科学基金项目（41730532，41576070，41376063，41676043，41606064，91958212），广东省基金团队项目（2017A030312002），促进海峡两岸科技合作联合基金（U150523），国家自然科学基金委员会共享航次（NORC2018-08）联合资助


详细信息

作者简介: 杨富东, 男, 1995年生, 在读硕士研究生, 研究方向为海洋深部地球物理.E-mail:yangfudong@scsio.ac.cn

通讯作者: 张佳政, 男, 1986年生, 博士, 研究方向为海洋深部地球物理.E-mail:jzzhang@scsio.ac.cn

中图分类号: P631

收稿日期:2019-04-12
修回日期:2019-07-18
上线日期:2020-02-05

A new method for shots and OBSs' relocation applying in three-dimensional seismic survey

YANG FuDong^1,2,4,,
ZHANG JiaZheng^1,2,,,
DU Feng³,
WANG Qiang^1,2,4,
PANG XinMing^1,2,4,
ZHAO MingHui^1,2,4,
QIU XueLin^1,2,4
1. Key Laboratory of Ocean and Marginal Sea Geology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China
2. Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou 510301, China
3. Hubei Key Laboratory of Earthquake Early Warning, Hubei Earthquake Agency, Wuhan 430071, China
4. College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China


More Information

Corresponding author: ZHANG JiaZheng,E-mail:jzzhang@scsio.ac.cn

MSC: P631

--> Received Date: 12 April 2019
Revised Date: 18 July 2019
Available Online: 05 February 2020


摘要
摘要:炮点和海底地震仪（ocean bottom seismometer，OBS）位置校正是三维地震数据处理的基本环节，也是获取高精度三维速度结构的关键所在.本文基于南海洋陆转换带（Continental-Oceanic-Transition zone，COT）IODP367/368钻探区开展的三维OBS深地震探测数据，开展了炮点及OBS位置校正研究，新的校正方法主要体现在三个方面：（1）利用连续三个炮点的平均航向对中间炮点进行位置校正，更真实地反映气枪枪阵与船体之间的软连接状态；（2）根据"滑动窗口"思想将海水声学速度阈值划分成N等份，通过循环测试获得全局最优的OBS位置校正结果，改进了前人方法只能获得局部最优解的问题；（3）针对单条测线穿过的OBS，通过加入其临近测线的直达水波走时，构成视双测线OBS位置校正法，提高了校正精度.49台OBS位置校正结果表明，除3台单测线法校正的OBS在垂直测线方向存在较大不确定性外，其余误差范围均为35 m左右.本文改进的OBS位置校正方法，不仅提高了单条测线穿过的OBS位置校正精度，保证后续三维地震结构研究的可靠性，而且为今后类似的OBS位置校正提供了经验和借鉴.
关键词: OBS位置校正/
炮点位置校正/
视双测线校正/
三维速度结构/
误差分析

Abstract:The position correction of shots and OBSs is the basic procedure of three-dimensional (3D) seismic data processing, and also a key step in acquiring high-precision 3D velocity structure. Based on the deep seismic data of the ocean bottom seismometer (OBS) experiment carried out in the IODP 367/368 drilling area on the Continental-Oceanic-Transition zone (COT) of South China Sea (SCS), this paper improved the previous shots and OBSs' relocation program mainly with three aspects. (1) The position of the intermediate shot is corrected by the average heading angle of three consecutive shots, which more realistically reflects the soft connection between the air gun array and the hull. (2) According to the Sliding Window idea, the water wave velocity threshold was divided into N equal parts, and the global optimal OBS position correction result could be obtained through the loop test, which solved the problem that the previous method could only obtain the local optimal solution; (3)To improve the accuracy of single line OBS relocation, travel-times were picked from in-line shots and nearest off-line shots, where a quasi-crossline model was built to improve the correction accuracy. 49 OBSs' positions were finally relocated. Except that the three OBSs corrected by single line method had large uncertainty in the vertical line direction, the remaining semi-major axis of error ellipses of all the OBSs were about 35 m. This approach not only makes better use of the high-quality data of the 3D OBS experiment in the IODP drilling area, but also provides accurate data base for the subsequent acquisition of the 3D velocity structure, and can provide solution to shots and OBS relocation of air-gun OBS survey in the future.
Key words:OBS relocation/
Shot relocation/
Quasi-crossline relocation method/
3D Seismic velocity structure/
Error analysis



PDF全文下载地址:

http://www.geophy.cn/data/article/export-pdf?id=dqwlxb_15354