The combination of velocity deviation and thorium normalization techniques to detect the Hartha Formation oil zones in the Qayyarah oilfield

This study aims to use the velocity deviation log (VDL) produced from porosity logs to detect the hydrocarbon accumulations of an oil reservoir in the Qayyarah oil field. This technique was applied to the Hartha oil Formation. Depending on the information of various cross plots, the Hartha Formation consists mainly of limestone with some interference of dolomite and varying proportions of shale. After comparing the VDL technique with the thorium normalization technique used previously for oil detecting, the compatibility between them was evident in most parts of the formation. This compatibility indicates the validity of the VDL technique in detecting the hydrocarbon sites in Hartha formation. The study demonstrated the presence of hydrocarbon accumulations in the upper parts of Hartha formation associated with porosity increasing and shale volume decreasing.