Generation of Pseudo Velocity Logs from Resistivity Logs and an Applied Example from Thrace

Abstract

This study used the well-log data belonging to two wells in the Thrace region drilled by the Turkish Petroleum Company (TPAO). A scale function was created from the correlation of sonic and resistivity logs in only one of these wells and the non-linear equation it defined was obtained to derive a pseudo velocity log. With the aid of this equation, a pseudo velocity log was derived for the second well drilled in the area using only resistivity log values. Additionally the % error values were calculated for both wells and the similarities between them investigated.

The true sonic logs and derived pseudo velocity logs from both wells were compared in the study. For both wells, the logs were observed to be similar. This study reveals that for any area with the aid of the non-linear equation based on the correlation between sonic and resistivity logs taken from one well, pseudo velocity logs can be derived using only resistivity log values for other wells in the region without requiring new sonic log measurements.