migration velocity analysis and prestack migration of ground-penetrating radar 地質雷達資料的偏移速度分析和疊前偏移
prestack migration is performed by reverse-time migration method based on maxwell's equations using time-domain finite-difference method 疊前偏移用時間域有限差分求解麥克斯韋方程組的逆時偏移方法實現(xiàn)。
numerical migration for typical models show that, in contrast to ray method, prestack wave motion migration can correctly image inhomogeneous media, and suppress multiple reflection wave effectively . prestack migration method presented in this paper should be developed to apply in observational teleseismic p waveform data, to study the inhomogeneity of crust and upper mantle 典型的介質模型數(shù)值分析表明,與射線方法相比,接收函數(shù)的波動方程疊前偏移能對橫向非均勻介質準確成像,不僅有較高的分辨率,而且對多次波有較明顯的壓制作用。
moreover, a series of solution to these difficulties are brought forward : applying the theory of fold related to fault to interpret complex structural belts in piedmont : analyzing the features of the surface and underground seismic reservoir prediction and porosity model construction to predicate effectively the texture and quality of sandbodies; using structural model to direct the construction of velocity model and process prestack migration imaging of seismic data; utilizing interval velocity to forecast reservoir pressure : improving the drilling technology for pressure detection and prompt protection of vertical well against incline well 并針對主要難點提出了解決對策:正確應用斷層相關褶皺理論解釋山前復雜改造、開展地表井下地震儲層與孔隙建模有效預測砂體結構與質量,利用有效構造建模指導速度建模與疊前偏移成像、開展層速度預測地層壓力與鉆井壓力檢測及快速防斜打直配套鉆井技術攻關等。
prestack migration method, based on wave motion equation, is also developed for receiver function, and compared with ray method . both p-to-s conversion wave and direct p phase contained in receiver function are migrated and imaged by reverse-time migration for data gather including all receiver functions recorded in all seismological stations for one event, and imaging profile is finally obtained by stacking for all events 本文還在接收函數(shù)射線反投影疊加成像的基礎上,提出了一種基于波動方程的接收函數(shù)疊前偏移成像方法,將同一事件接收函數(shù)中的轉換波和直達p波震相以各自的速度向深度方向逆時延拓成像,并通過不同慢度接收函數(shù)的疊加,得到最終的偏移成像結果。