Internal Multiple Attenation by OVT Migration and its Application in Carbonate Rock Environment

Due to the strong impedance interface in carbonate, the consequent multiples seriously infuence velocity estimation, and be wrongly interpreted as primaries. We present a novel workflow for attenuation of internal multiples, applicable to data with wide-azimuth acquisition. First, we sort data into the offset vector tile(OVT) domain with well-distribution in offset and azimuth, such OVT gathera are suitable for noise attenuation. Next, we finish pre-stack time migration using OVT gathers as input and output, supressing multiples during migration, and then we found the fact that internal multiples have different distribution of energy to primaries in the OVT domain, we propose a part-stack strategy in the OVT domain aimed at structural interpretation, making further improvement on the imaging quality of primary. We apply this workflow to data from Tarim basin, China. Our results demonstrate overall improvements in multiple attenuation and reveal weak primary events previously obscured by multiples.