Journal of Scientific Engineering Advances

Abstract

Three principal approaches play a significant role in sustaining oil and gas production: the exploration of new fields, the implementation of development strategies for producing fields based on their natural geological potential, and the reassessment of the hydrocarbon potential of suspended or abandoned fields with the aim of bringing them back into production.

The exploration of new fields is a long-term process that generally requires substantial capital investment. In Azerbaijan, the current geological and technological development status of producing fields primarily allows the implementation of measures aimed at reducing the rate of production decline or compensating for it to the greatest extent possible.

From the perspective of securing additional production within a relatively short period and at comparatively low cost, the reassessment of the hydrocarbon potential of suspended or abandoned fields and, where economically and technically justified, their redevelopment is of considerable interest. A reliable solution to this challenge requires investigation of the field’s natural geological characteristics using modern approaches, including analysis of field- and well-level development and production performance and accurate identification of both objective (geological) and subjective causes of observed changes.

At present, 81 commercially significant oil and gas fields have been discovered in Azerbaijan. Over the years, up to 15 of these fields have either been suspended or taken out of production.

This paper presents the Gürgan Deniz Field as a case study for evaluating the hydrocarbon potential of suspended or abandoned fields. It analyzes the investigations conducted to assess the feasibility of returning the field to production, the redevelopment program developed on the basis of these results, the studies and operations performed in the first well drilled under this program, and the corresponding well test results. Recommendations for the subsequent full-scale redevelopment of the field are also presented.

The results of these investigations, together with the project developed on their basis to determine the target location of the appraisal well and initiate drilling operations, were prepared and approved in 2021.

The well was drilled by Glolynx Azerbaijan LLC, while accurate well placement, trajectory steering, and trajectory optimization were carried out by the company’s geology and drilling teams. The application of new geological and drilling approaches, together with the subsequent well test results, confirmed the validity of the analytical studies and methodologies used to reassess the field’s hydrocarbon potential. These results provided the basis for initiating a new phase of development at the Gürgan Deniz Field, which had previously been taken out of production after being considered depleted.

The integrated geological and reservoir evaluation, optimized drilling and well completion solutions, and measurement operations performed by the drilling company’s specialists enabled the reassessment of hydrocarbon saturation in intervals previously considered water-bearing or depleted. These activities resulted in the identification of new hydrocarbon-bearing zones, opened new opportunities for subsequent wells, and provided a basis for optimizing the number of future wells as well as their drilling and completion programs.

Through the application of integrated geoscience and drilling engineering solutions, the first well drilled in the Gürgan Deniz Field after many years of inactivity was successfully completed and delivered to the Client within a shorter-than-planned timeframe and at a lower-than-planned cost. The well achieved a record in SOCAR’s history in terms of both the horizontal section length and the screen-completed interval, with an 848 m screened section.

Within the reservoir interval, the well trajectory was steered, optimized, and proactively adjusted by the geology and engineering teams without the use of additional high-cost technologies such as dedicated geosteering equipment. The well trajectory was successfully steered away from water-bearing zones, and the well was completed at a measured depth of 2,360 m, with the final trajectory positioned 16 m above and 4 m to the right of the originally planned target. The screen completion was successfully performed, and the well was brought on production at an oil production rate approximately 3–4 times higher than the rate originally anticipated in the well design.