Analysis of the 4D Signal at the Volve Field NCS - An Open Subsurface Dataset

In 2018, Equinor released to the public an open subsurface dataset comprising all the data of the Volve Oil field from the central Norwegian North Sea. The dataset includes 4D seismic that we interpret, calibrate and quantify to better understand the distribution of water sweep in the reservoir.

Calibration of a dynamic Petro-Elastic Model (PEM) is a key part of the 4D interpretation. Saturation changes in the reservoir are determined to be the primary reason for a 4D signal with a maximum impedance change of 5% expected. The PEM is then combined with 4D forward modelling of well logs to establish links between the the character of the 4D signal and water sweep in the three reservoir zones at Volve. Discrepancies between production logging results and those which best match the 4D seismic response can be combined with the qualitative understanding of the seismic uncertainty to suggest improvements to the reservoir simulation model.