Petrophysical Properties of the Upper Qamchuqa Formation in the Jambur Oil Field

Abstract

The Qamchaq Formation makes up the upper Cretaceous reservoir of the Jambur oil field and is responsible for most of the hydrocarbon production in this complicated carbonate reservoir. The petrophysical characteristics of the rocks and fluids differ in various sections of the region. The first step in constructing an acceptable geological model is to identify reservoir characteristics, geological features, lithological characteristics, and hydrocarbon zones to accurately forecast future reservoir performance during the development phase. The goal of this paper is to describe the petrophysical properties and composition of the upper Qamachq formation based on an analysis of a set of conventional well log data using Techlog 2018 software to make assessment integration easier by offering a variety of functions for processing data and showing results. According to the study, the lithofacies vary from northwest to southeast. The lithology in the northwest is limestone to dolomite; basinal Balambo facies replace it in the southeast of the structure. More parameter estimates include 9% matrix porosity, 51% water saturation, and a net-to-gross ratio of 20%, indicating beneficial petrophysical characteristics in the northwest of the structure that contribute significantly to production, as opposed to the southwest region, which has poor physical characteristics. The permeability derived from log data was inaccurate since the Wyllie-Rose formula's permeability coefficient was designed for sandstone and would not be acceptable for carbonate rock; furthermore, the Coates formula has underestimated the permeability because the permeability coefficient needs to be improved by matching it to the core information for each well.