Successful Well Testing Operations by Using a Single Trip Retrievable Isolation and Testing Packer in Ghasha Appraisal Well Offshore Abu Dhabi

Abstract

The discovery of offshore sour and corrosive gas reservoirs and the need to satisfactorily drill and produce them began in the late 1950's. The Ghasha 15 well includes deep oil / gas reservoirs containing up to 38% H2S and 7% of CO2. The objective was to perform safe and efficient drilling and several well testing operations in a highly corrosive environment with a rig that was located in a stand-alone offshore location in Abu Dhabi. The well was an exploration well in a location considered wild or remote well; there was no tower or platform facility with pipe lines to support the well testing operations available. 14 x well drilled previously were unsuccessful in obtaining the necessary reservoir data to prove deliverability. These challenges required the use of state of the art technology and highly reliable down hole equipment to subsequently enable successful exploration & appraisal of future UAE giant gas field development optimization. Among other down hole tools and surface equipment used, highly sophisticated DST tools including HPHT high integrity packer, acoustic wireless telemetry systems, Dual Ported Slick Joints (DPSJ), flanged connections, surface close loop well testing package, special H2S and fire & gas detection systems and dispersion modelling were designed to successfully deliver the required data for field developments. Attention to detail, rigorous planning, team work, multidiscipline input and approach were some of the key success factors in delivering the objectives in a safe and efficient manner. While many drilling, data gathering, surface and down hole tool solutions were employed, this abstract will focus solely on the packer equipment and deliverability