Anisotropic model building by integrating welltie and checkshot for Garden Banks of GoM

Abstract

Summary In order to improve depth positioning and structural accuracy, we b uild an anisotropic velocity model for imaging Northeastern (NE) Garden Banks in the Gulf of Mexico (GoM). We assume vertical transverse isotropy (VTI) and derive Thomsen’s δ by comparing seismic and well data. Both welltie and checkshot data indicate a twolayer δ trend in NE Garden Banks: low δ shallow and high δ deeper. The interface between the two δ zones corresponds to a distinct seismic reflector – the base of a mass transport complex which is also a local maximum in the velocity. Using this two-layer δ model and a scanned Thomsen’s e model, we carry out anisotropic (VTI) imaging. The VTI imaging reduces misties by more than 80% compared to the original isotropic imaging.