Curvilinear wave-equation angle transform: Caustics, turning rays, absence of kinematic artifacts
نویسنده
چکیده
Migration of seismic reflection data to common image-point gathers is an integral part of both migration velocity analysis (MVA) and amplitude (AVA) analysis. Its applicability in complex geology depends on whether these gathers will be artifact free, and is related to the formation of caustics and turning ‘rays’ due to the heterogeneity of the velocity model used. Here, we discuss an angle transform – which by methods of (survey-sinking or shot-geophone) wave-equation migration maps data into image gathers – in special curvilinear coordinates that remains artifact free in the presence of caustics while allowing turning ‘rays’ to illuminate steeply dipping reflectors.
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تاریخ انتشار 2007