Improved subsalt imaging using TTI anisotropy and reverse time migration scans

Abstract

We present an advanced velocity model building and imaging methodology that resulted in significant enhancements in defining the salt flanks with overhangs and subsalt structures. The key technologies used were (a) True Azimuth Multiple Elimination (TAME), (b) Tilted Transverse Isotropy (TTI) model building (FAN), (c) TTI Reverse Time Migration (RTM), (d) RTM Delayed Imaging Time (DIT) scans and (e) post-migration multiple attenuation. Approximately 39 OCS blocks of the Lena narrow-azimuth survey located in the Mississippi Canyon area of the Gulf of Mexico were imaged. The area was previously imaged with the Vertical Transverse Isotropy (VTI) Kirchhoff migration. Significant improvements have been achieved by reprocessing the same data with the new imaging methodology.

Adequate velocity model as a basis for effective seismic imaging when mapping hydrocarbon traps associated with salt domes

“…Èñ-ïîëüçîâàíèå àíèçîòðîïíûõ ìîäåëåé ñ âåðòèêàëü-íîé îñüþ ñèììåòðèè ïðè ñóùåñòâåííî íàêëîí-íîì çàëåãàíèè ñëîåâ ìîaeåò çíà÷èòåëüíî ïîíè-çèòü ýôôåêòèâíîñòü ïðîöåäóð ïîñòðîåíèÿ ñåéñ-ìè÷åñêèõ èçîáðàaeåíèé Bowling et al, 2010;Epili et al, 2011;Swanston et al, 2011;. Ýòî äåìîíñòðèðó-åòñÿ íà ðèñ.…”