Challenges in processing variable‐depth streamer data

Abstract

Variable-depth streamer acquisition is emerging as a key technique for providing wide bandwidth seismic data. With several data sets acquired across the world, it has consistently produced high quality images in terms of seismic resolution, layer stratigraphy and low-frequency penetration. By varying receiver depth, variable-depth streamer acquisition introduces receiver ghost diversity over different offsets. Such diversity enables a joint deconvolution method to fully remove the receiver ghost. Variable-depth streamer data also tends to be less noisy due to the deep tow of cables. These two factors allow variabledepth streamer data to have a spectrum from 2.5 Hz up to the source notch. Challenges in processing include: how to maintain the full bandwidth in the data, how to effectively remove multiples, and how to robustly build a velocity model. This paper will discuss each of these challenges and their solutions.

Challenges of Pre-Salt Imaging in Brazil’s Santos Basin - A Case Study on a Variable-Depth Streamer Data Set

“…Due to the differences in data associated with variable-depth streamers, the conventional processing flow needs to be modified to better serve it. The key elements of the modifications are as follows: maintaining the full bandwidth in the data, improving variable-depth streamer SRME, and deghosting the imaging gathers for velocity updates (Lin et al 2011). The variations in cable depth create a diverse ghost response, requiring modifications for both SRME and velocity model building.…”