Comprehensive Analysis of the Libyan LGC Field: OGIP Estimation and Reservoir Drive Mechanism Identification: Comprehensive Analysis of the Libyan LGC Field: OGIP Estimation and Reservoir Drive Mechanism Identification

Mustafa   Sharrad; مرام   كنز

Authors

Mustafa Omar Sharrad 2Department of Petroleum Engineering, Libyan Academy for Postgraduate Studies – Western Coast Branch, Al-Ajailat,, Libya
مرام محمود كنز Maram Mahmoud Kanz Department of Petroleum Engineering, Faculty of Engineering – Sabratha, Sabratha University – Libya

Keywords:

Original Gas in Place, Gas Condensate, Water Drive, Material Balance, Stewart Mixing Rules, Sutton Correlations.

Abstract

Accurate estimation of the Original Gas in Place (OGIP) and understanding reservoir drive mechanisms are essential for efficient gas field development and management. This study investigates the Libyan LGC gas-condensate reservoir using two well-established techniques: the volumetric method and the material balance equation (MBE).

The dual-method approach integrates static geological parameters and dynamic production data to reduce uncertainty and improve reservoir modeling. Stewart’s mixing rules were applied for known gas compositions, while Sutton’s correlations were used when compositions were unknown.

The Volumetric Method estimated OGIP at 8128 Bscf (known) and 8259 Bscf (unknown), while the MBE method estimated it at 8172 Bscf...

The identification of the reservoir drive mechanism was based on the analysis of p/z versus cumulative gas production behavior. The observed deviation from linearity, without a pronounced upward curvature, indicates the presence of aquifer support that is moderate rather than dominant, which is characteristic of a moderate water-drive gas reservoir.

This study underscores the value of methodological integration for reliable reserve estimation and effective reservoir management, and supports better reservoir modeling and development planning.

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Comprehensive Analysis of the Libyan LGC Field: OGIP Estimation and Reservoir Drive Mechanism Identification