Investigation of the origins of rapid gas-water contact rise and excess water production in naturally fractured reservoirs: a case study

ABSTRACT

Efficient gas production management is an important task for oil and gas companies. Water production is a critical problem in gas reservoirs which may result in early abandonment of many wells, reservoir and low recovery factor. In Homa gas field, since 2012, a rapid increase in water–gas contact of 20 meters per year has been observed, so that in 2018, an average of 40 to 50% of the reservoir area has become water invaded. The calculations indicated an approximate amount of 1.5 to 2.37 Trillions of standard cubic feet of trapped gas in the reservoir. This phenomenon is of great importance in the reduction of reservoir recovery. In this study, an integrated approach is proposed for determination of source of water production in gas production wells of a fractured reservoir in the south of Iran. This study showed a water encroachment from highly fractured aquifer with high-speed invasion in fracture networks and considerable bypassed gas in matrix blocks that highly reduces recovery factor and it was not early detectable by classical methods. The proposed approach can be applied for new fields under development in the region.

KEYWORDS:

• Homa gas field
• imbibition
• gas production
• water level
• water production
• fractured network

Acknowledgments

The authors would like to gratefully acknowledge and show appreciation to the Department of Petroleum Engineering, Faculty of Engineering, Marvdasht Islamic Azad University, Marvdasht, Iran for supporting this work.

Additional information

Funding

This work was supported by the Marvdasht Islamic Azad University [N/A].

Notes on contributors

Mohammad Ghasem Akbarifard

Mohammad Ghasem Akbarifard is a full time PhD student of Chemical Engineering at Marvdasht Islamic Azad University, Iran.

Amin Azdarpour

Amin Azdarpour is working as a full time Assistant Professor at Marvdasht Islamic Azad University, Iran.

Zahra Arab Aboosadi

ZahraArab Aboosadi is working as a full time Assistant Professor at Marvdasht Islamic Azad University, Iran.

Bizhan Honarvar

Bizhan Honarvar is working as a full time Professor at Marvdasht Islamic Azad University, Iran.

Moein Nabipour

Moein Nabipour is working as a full time Assistant Professor at Marvdasht Islamic Azad University, Iran.