Study of Petrophysical Properties of the Yamama Formation in Siba Oilfield

Abstract

Evaluating a reservoir to looking for hydrocarbon bearing zones, by determining the petrophysical properties in two wells of the Yamama Formation in Siba field using Schlumberger Techlog software. Three porosity logs were used to identify lithology using MN and MID cross plots. Shale volume were calculated using gamma ray log in well Sb-6ST1 and corrected gamma ray in well Sb-5B. Sonic log was used to calculate porosity in bad hole intervals while from density log at in-gauge intervals. Moreover, water saturation was computed from the modified Simandoux equation and compared to the Archie equation. Finally, Permeability was estimated using a flow zone indicator. The results show that the Yamama Formation is found to be mainly limestone that confirmed by cuttings description and this lithology intermixed with some dolomite, in addition to gas and secondary porosity effects. Generally, the formation is considered clean due to the low shale volume in both wells with the elimination of the uranium effect in well Sb-5B. The calculated porosity was validated by core porosity in YC and YD units. Modified Simandoux gives a better estimation than the Archie equation since it takes into account the conductive of matrix in addition to the fluid conductivity. Five equations were obtained from porosity permeability relationship of core data based on five hydraulic flow units reorganized from the cross plot of reservoir quality index against normalized porosity index. The overall interpretation showed that YC and YD units are the best quality hydrocarbon units in the Yamama Formation, while YA came in the second importance and has properties better than YB. Moreover, YE and YFG are poor units due to high water saturation.

Estimation of the Petrophysical Properties of the Lower Cretaceous Yamama (YC) Formation in Siba Field

“…The Shatt al-Arab, which acts as the political boundary between Iraq and Iran, flanks the city to the northeast and north. In contrast, the northern and northeastern portions, and the region near the Shatt al-Arab [32][33][34][35]. The Siba field's geology is a NE-SW trending anticline with a low relief structure that exhibits a little dip and a moderate fracture system.…”

Processing and analyzing data to predict earthquakes in Iraq

“…The first part of the earthquake catalog is from 1900 to the end of 2009. It includes more than 18,000 earthquakes [9], and the following are the sources of seismic data for the study area within the catalog used in this study: 1) Iraqi Seismological Network (ISN) 2) International Seismological Center -Global Seismic Model (ISC-GEM) 3) International Seismological Center (ISC) 4) Euro-Mediterranean Seismological Center (EMSC) 5) Geological Survey Catalog 6) Universal central moment tensor (CMT universal) 7) National Geophysical Data Center/Wetlands Database (NGDC/WDS) 8) USGS Centennial Catalog 9) Ambrasys' extensive work cataloging earthquakes in the Mechanistic Age in the Middle East Previously recorded earthquake data between 2009 and 2014 have also been added to ISN and the stations are: Baghdad (BHD), Mosul (MSL), Rutba (RTB), Nasiriyah (NSR), Badra (IBDR), Kirkuk (IKRK) [10]. And from 2014 to 2019 from the earthquake laboratory at the University of Basra / College of Science / and from the stations: Basra, Nasiriyah, Samawah, Amarah, Karbala, Anbar, Kirkuk, Sulaymaniyah, Dohuk [11].…”