Evaluation of Reservoir Quality of upper Dalan formation using Petrophysical data in one of the gas fields in southern Iran
Subject Areas : Petroleum Reservoir GeologyParya Zendehdel 1 , amir karimian torghabeh 2
1 - Petroleum Geology Group, Department of Earth Sciences, Faculty of Science, Shiraz University, Iran
2 - PhD Department of Geology, Faculty of Sciences, Ferdowsi University of Mashhad and PhD Petroleum Geology Group, Department of Earth Sciences, Faculty of Science, Shiraz University
Keywords: Petrophysics, gas field, EOR, upper Dalan formation, reservoir quality.,
Abstract :
Today, reservoir rock evaluation is very important in the oil industry. The ability of petrophysical evaluation is very important in determining reservoir zones and investigating them in petroleum geology. The studied gas field is one of the gas fields in the south of Iran in the Zagros sedimentary basin. In this research, using petrophysical data and porosity-permeability information of the cores and with the help of the possible evaluation method, the petrophysical parameters of the upper Dalan Formation were evaluated in two wells 4 and 6. The purpose of the research is to check the quality of the studied gas field and evaluate the reservoir properties using petrophysical studies. According to the results of this petrophysical evaluation, in the upper Dalan Formation in wells 4 and 6, the average shale volume is 1.7 and 2.4, respectively, the average water saturation is 30, 22.4, respectively, and the average effective porosity is 3.7 and 4.4, respectively. 6 and the ratio of useful thickness to total thickness is 0.68 and 0.92 respectively.The closer the value of this parameter is to 1, the studied formation has more reservoir quality. For a more detailed investigation, the upper Dalan formation in the studied field was divided into 3 zones (UD-3-UD-1) and UD-3 zone was divided into two sublayers (UD-3b-UD-3a). UD-2 zone with the dominant lithology of dolomite and some calcite, due to the volume of gas and greater porosity than other zones, was recognized as the best reservoir horizon. Such studies are used to increase production and EOR.