Abstract

Prior 2001, the overall potential as well as the viability of the long-term development of the Lower Burgan Sandstone reservoir in Sabiriyah field (SA LB) in North Kuwait were somewhat uncertain. This was mainly due to two factors; wet crude handling limited capacity (given that over 70% of the producers were wet) and the fact that the reservoir produced about 65% of its reserves. Additional penetrations into this mature reservoir out side its 1998 foot print (through deepening other reservoirs’ new wells to SA LB), have resulted in extending SA LB reservoir both areally and vertically indicating new development frontiers and promising a significantly increased reservoir potential.

At that time, a multi-disciplinary team was formed to evaluate the reservoir. Better understanding of the reservoir geology, rock and fluid description, and well’s performance provided the frame to make effective changes in terms of management as well as development options of this high oil API/naturally pressure supported reservoir. 

The well-integrated SA LB team (four to five members) comprises petroleum engineers, geologists, and reservoir engineers, with petrophysical and geophysical support. The great efficiency of the teamwork method was combined with an excellent atmosphere of communication and collaboration with the operational and service company’s personnel. The new teamworking environment has yielded significant benefit in resource and technology utilization.

The previous organization approach often compromised SA LB production/potential through focusing on the other water flooded reservoirs and treated it as a swing producer. It suffered from the absence of a proper definition of the reservoir before commitment of non-representive development plan as a swing producer with no infill opportunities.

This paper demonstrates and emphasizes the importance of developing an accurate reservoir description, realistic/flexible development plan, and comprehensive management through the joint efforts of the geologists and engineers.

Introduction

Lower Burgan reservoir located in Sabiriyah field (North Kuwait) was discovered in 1957. First commercial oil production from this multilayerd sandstone reservoir started back in 1964. Operating under active bottom water drive as well as edge water drive, the well spacing varies with close well spacing in the crestal area and wider spacing in the Southern area.

SA LB reservoir is the second largest Sabiriyah reservoir in terms of STOOIP, and reserves. It is the largest contributor to Sabiriyah oil production, producing 40% of the Sabiriyah daily oil production. Lower Burgan oil is the highest API gravity crude in Sabiriyah helping meeting crude quality export requirement for the only gathering center in the field. Amongst 3 oil-producing reservoirs, which are at various stages of development, it has contributed about 75% of the total Sabiriyah cumulative oil production as of December 2003. Significant amount of SA LB historical production has come from the lower part of the reservoir (M Sand) where the pattern of water influx is very well understood. Most of the historical production and the majority of remaining reserves are in the upper part of the reservoir (L Sand) where the pressure support and water influx are relatively well understood.