川東灰巖出露區地震采集觀測系統優化設計及應用

中圖分類號：P631 文獻標識碼：A DOI：10.13810/j.cnki.issn.1000-7210.20240471

Abstract：Due to the high and steep underground structure in the limestone outcropping area of the eastern Sichuan Basin，the conventional geometryhas some problems，such as uneven ilumination and insuficient partial ilumination energy.Forthe high and steep structure of the eastern Sichuan Basin with high-precision seismic imaging，seismic ilumination analysis is an important method to guide the optimized design of seismic acquisition geometry in the region. By combining the surface and underground geological conditions in limestone outcropping areas of the eastern Sichuan Basin，this paper establishes the demonstration technology and process of geometry encryption based on seismic ilumination analysis.By conducting the design and demonstration of geometry encryption of the underlying structure in the limestone outeropping areas，the seismic illumination energy of the local shadow area of the geological target is effectively improved. Firstly，the surface encryption range is determined by adopting the 2D forward model for reverse illuminationanalysis，and then by employing the 3D geologicalmodel forforward modelinganalysis combined with the actual seismic data analysis，the acquisition geometry encryption scheme suitable for the limestone outcropping area in eastern Sichuan Basin is obtained.The technological implementation and application show that adding receiving linesat the topofthe structurecanefectively improve the seismic imaging effectof the highand steep complex structure area inthe east Sichuan Basin，and a technically effctive and economically feasible encryption scheme for the geometry can be obtained.

Keywords： eastern Sichuan area，limestone outcropping areas，high precision，seismic illmination，geometry，signal to noise ratio （SNR）

王曉陽，王勤耕，巫芙蓉，等，川東灰巖出露區地震采集觀測系統優化設計及應用[J].石油地球物理勘探， 2025，60（4） ：861-869.

WANG Xiaoyang，WANG Qingeng，WU Furong，et al. Optimized design and application of seismic acquisition geometry in outcropping areas of limestone in eastern Sichuan Basin[J]. Oil Geophysical Prospecting，2025， 60（4） ：861-869.

0 引言

隨著油氣勘探開發力度的不斷加大，目標更加復雜、隱蔽，尤其在高陡構造區提升地震資料精度的需求也日趨迫切。地震采集觀測系統優化設計能夠有效提升地下目標的地震照明能量，進一步改善復雜構造的成像效果。因此，利用地震照明分析優化設計采集觀測系統成為了提升高陡構造地震資料品質與成像精度的有效手段之一。

地震照明分析可分為射線類照明和波動方程類照明，眾多學者對地震照明的方法原理及其在觀測系統設計中的應用進行了大量研究。射線照明可以描述非均勻介質中不同角度的照明程度1，在一定程度上指導了采集觀測系統設計，但該方法是建立在高頻漸進近似基礎上，不能處理復雜介質散射、衍射等波動現象[2-4]。2002年，波動方程理論引入到地震照明分析中，建立了基于波動理論不同類型照明的計算方法，并提出了地下照明量度的概念，也就是地震波在地下傳播過程的能量大小分布[5。在此基礎上，通過雙程波單向照明與雙向照明等不同計算方法進行數值模擬[6-9]，提出了根據地面最優炮點分布與最優排列接收參數，以及局部加炮或加道方法[10來解決目的層反射能量不均勻的問題[11]。雙程波雙向照明方法精度較高，但效率較低，難以應用于實際生產，而單程波雙向照明方法的計算效率具有一定優勢[12-14]。……