Rock physics attributes analysis for identification and characterization of fluid content at hydrocarbon reservoirs - revisiting the Viking Graben basin dataset

Abstract

In the characterization of hydrocarbon reservoir, most of methodologies used in rock physics or seismic reflection are based on the physical properties analysis of rocks which are associated to anomalous effects in seismic sections. These anomalies are, many often, associated to indicators of fluids (oil, gas and/or water) in the hydrocarbon reservoir. In this work, we perform a study in order to characterize a hydrocarbon reservoir at north Viking Graben region, in the North Sea. In addition to the seismic data, well-logs from two locations (wells A e B) were also used in our analysis. However, in our data set analysis, beyond to perform AVO analysis, Vp/Vs versus impedance (Ip) and Vp/Vs - Φ we applied the trend angle methodology and well-logs data set analysis as well as Gassmann fluid substitution. Through AVO analysis in the re-processing of Viking Graben seismic data set, where found three anomalous zones with a high potential for the presence of fluids (gas/oil). Thus using templates of rock-physics and the analysis by attributes (trend angle) to classifying the fluids and determinate the possibility of gas-sand that are present at wells A and B.