InterPore2025

Mineralogical and Saline Water Effects on Sandstone Reservoir in Southern Indus Basin: Unlocking EOR and CO2 Storage Potential

21 May 2025, 14:50

15m

Oral Presentation (MS06-A) Physics of multiphase flow in diverse porous media MS06-A

Speaker

Bilal Shams (Dawood University Of Engineering and Technology)

Description

ABSTRACT
The sandstone reservoirs of the Southern Indus Basin, particularly the ones in the Pab range near Winder, Baluchistan, Pakistan, have yet to be exploited with regard to the potential for enhanced oil recovery (EOR) and carbon capture and storage (CCS). The preliminary study on mineralogical composition and the effects of saline water concentration on wettability alteration and interfacial tension (IFT) has been conducted, with implications for both on hydrocarbon recovery and on CO₂ storage.
XRD analysis shows the mineralogical profile of the sandstone, which consists of quartz at 54.67%, and other minerals, such as hematite and calcium oxide. Quartz is a key mineral that maintains structural stability and supports favorable fluid-rock interactions. The presence of hematite and calcium oxide affects the reactivity and wettability. These mineralogical characteristics are important in optimizing EOR and creating the right conditions for CO₂ storage by modifying petrophysical properties such as pore connectivity and surface wettability.
Core plugs were prepared from sandstone outcrop samples, and experimental tests were performed. Saline water flooding was analyzed through IFT measurements by pendant drop method and wettability tests by sessile drop technique across the range of saline concentrations from 1,000 to 35,000 ppm. Spontaneous imbibition tests were also conducted to find the oil recovery efficiency under various salinity levels. The results showed that increased saline concentration decreased IFT dramatically and changed the wettability from oil-wet to water-wet, improving oil displacement.
These results are consistent with international research on analogous quartz-rich reservoirs, which have been proven to be suitable for both EOR and CO₂ geologic storage. The mineral composition and salinity-induced changes in petrophysical properties are consistent with conditions that have been demonstrated to enhance the efficiency of CO₂ trapping by capillary and dissolution mechanisms.
This pioneering research fills a critical gap in understanding the interplay between mineralogy, saline water concentration and reservoir performance in the Southern Indus Basin. It offers a path forward for integrating EOR and CCS in Pakistan, utilizing local geological resources for energy sustainability and climate change mitigation.