热带海洋学报 ›› 2022, Vol. 41 ›› Issue (1): 194-203.doi: 10.11978/2020153

• 海洋地球物理学 • 上一篇    下一篇

主动源海底地震仪横波模型的自动搜索与非唯一性分析*

张浩宇1,2,3,4,5(), 丘学林1,2,3,4(), 黄海波1,2,3   

  1. 1. 中国科学院边缘海与大洋地质重点实验室, 中国科学院南海海洋研究所, 广东 广州 510301
    2. 中国科学院南海生态环境工程创新研究院, 广东 广州 510301
    3. 南方海洋科学与工程广东省实验室(广州), 广东 广州 511458
    4. 中国科学院大学, 北京 100049
    5. 中国石油化工股份有限公司石油物探技术研究院, 江苏 南京 211103
  • 收稿日期:2020-12-28 修回日期:2021-02-26 出版日期:2022-01-10 发布日期:2021-03-04
  • 通讯作者: 丘学林
  • 作者简介:张浩宇(1995—), 男, 博士, 研究方向为海洋地震探测技术。email: zhanghy435.swty@sinopec.com
  • 基金资助:
    国家自然科学基金项目(41674092);国家自然科学基金项目(41676045);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(GML2019ZD0204)

Automatic search and non-uniqueness analysis of shear wave models from active Ocean Bottom Seismometer data

ZHANG Haoyu1,2,3,4,5(), QIU Xuelin1,2,3,4(), HUANG Haibo1,2,3   

  1. 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. Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
    4. University of Chinese Academy of Sciences, Beijing 100049, China
    5. SINOPEC Geophysical Research Institute, Nanjing 211103, China
  • Received:2020-12-28 Revised:2021-02-26 Online:2022-01-10 Published:2021-03-04
  • Contact: QIU Xuelin
  • Supported by:
    National Natural Science Foundation of China(41674092);National Natural Science Foundation of China(41676045);Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)(GML2019ZD0204)

摘要:

主动源海底地震仪探测在海底结构的研究中发挥着重要作用, 其中转换横波数据模拟为研究海底构造和物质属性提供了精确依据。本文针对现行转换横波模拟技术存在的步骤繁琐、难以确保最优解和无法进行非唯一性分析等问题进行研究, 提出了基于模型解空间和目标函数的模拟技术, 形成了主动源转换横波数据模拟的新方法, 该方法可借助计算机程序实现结构模拟的自动化。在南海西北陆缘的西沙地块OBS2013-3测线上对该方法进行验证, 分别利用单台PPS震相和全体台站的PSS震相走时数据进行模拟试验。结果表明, 本文的方法能够提供对于最优模型的快速、准确搜索和非唯一性范围的估计。这一方法有助于提高主动源海底地震仪转换横波数据模拟的效率, 并为结果的可靠性和稳定性提供更好的保障。

关键词: 海底地震仪(OBS), 转换横波, 模拟方法, 自动搜索, 非唯一性分析

Abstract:

Active Ocean Bottom Seismometer (OBS) prospecting is taking the leading role in illuminating submarine structures, among which converted shear wave modeling provides precise constrains on seismic structures and lithology. Due to the tedious procedures involved, difficulties in reaching optimal solution and insufficiency in non-uniqueness analysis in the present modeling method, we propose a new modeling method based on model solution space and objective function. Automatic modeling of converted shear waves can be realized using this new method with the aid of computer programming. This method is tested for its utilities in a realistic wide-angle OBS seismic profile, OBS2013-3, traversing the Xisha block, the northwestern South China Sea continental margin. PPS phases from a single station and PSS phases from all stations are employed in the case to model Vp/Vs ratios in sediments and the crust, respectively, where Vp is compressional wave velocity and Vs is shear wave velocity. Capacities of the new method to provide quick and accurate search for optimal models and estimates for modeling non-uniqueness are demonstrated. The new method is expected to promote the efficiency of converted shear wave modeling using OBS data and lay solid foundation for reliability and stability of modeling results.

Key words: Ocean Bottom Seismometer (OBS), converted shear wave, modeling method, automatic search, non-uniqueness analysis

中图分类号: 

  • P712.83