Generation of a Regional Fluid Database for Gas Condensate Assets in a Thrusted Carbonate Environment of the Northern Emirates

Abstract

Sharjah National Oil Corporation (SNOC) operates 4 onshore fields, the largest of which has been in production since the 1980's, in addition to over 50 years of exploration activity in the region. The producing fields exhibit a wide range of condensate-gas ratio (CGR) productivity and other properties. The scope of this paper is to discuss how the data from these exploration and development wells was combined to develop a trend of the fluid properties within the Northern Emirates to assist in the Future SNOC activities. A detailed data scouting and processing workflow was undertaken and all available legacy pressure-volume-temperature (PVT) reports were digitized. All available separator recombined samples reports and bottomhole sample reports were compiled into a master database. The well test reports were thoroughly examined to understand the field operations and determine the reliability of the PVT reports while the fluid samples were collected during the well tests. An equation of state was generated for each field using all available information taking into account their production history over 30+ years and the results were then used for the regional PVT study. A distinct trend of CGRs, specific gravity and other reservoir fluid properties were observed which co-related with the formations. These prospects which are spread out all over the Emirate of Sharjah were compared on the same parameters to develop a regional guideline. A regional trend of changing fluid properties was also observed which helps define the fluid properties expected in the Thamama Group formations in the Northern Emirates from any exploration well. The results will assist in determining the valuation of any exploration prospect if it is deemed successful and also plan ahead for the value of the prize. These trends also helped fill in missing data and perform quality control (QC) on older fields where comprehensive lab data was unavailable. In some cases, gas condensate fluid properties were unattainable at the mature stage of the field and this study provided the necessary information to plan enhanced recovery opportunities. This paper aims to be a leading reference for the PVT fluid properties in the complex Thamama Group of the Northern Emirates to support future exploration and development activities. The regional data provides a strong correlation and this information is novel in terms of utilizing legacy data for potential opportunities. The new database also helps QC the dataset of existing PVT reports along with aiding in identifying the sources of hydrocarbon origin in this region.