oa Utilizing Massive 3DVSP Data for Improved Structural Definition of Jurassic Reservoirs in Raudhatain and Sabiriyah Fields, Kuwait

The Raudhatain and Sabiriyah fields are situated in north Kuwait. In the Raudhatain Field, the Jurassic<br>reservoirs, Najmah-Sargelu and Marrat ,have two distinct northern and southern culminations,<br>separated by an intervening fault boundary; while in the Sabiriyah field the reservoirs are divided into<br>up thrown and down thrown sides along a NNE-SSW fault. In both the fields, the faults and associated<br>fracture networks have a significant impact on production.<br>In 2009, Kuwait Oil Company (KOC) acquired two massive 3DVSP survey in the Raudhatain and<br>Sabiriyah fields. The primary objective of the surveys were to improve the structural definition of the<br>Jurassic reservoirs, especially the Marrat reservoir and also to test the feasibility of characterizing the<br>fractured reservoirs using anisotropy information. The surveys consisted of 100-level multi-component<br>tool, combined with around 10,000 source points covering an area of around 64 square kilometers.<br>This is probably one of the largest onshore surveys in the region.<br>The high resolution and better signal to noise ratio in the VSP data, is expected to provide improved<br>structural definition in the vicinity of the well. This information will be utilized in locating future<br>appraisal wells. In order to reduce the survey time, a test was also conducted on four 2D lines of 6km<br>length, using four fleets of two vibrators, utilizing the High Fidelity Vibratory Seismic (HFVS) technique.<br>While the processing is ongoing, the results of the test are expected to produce data quality which will<br>be equivalent or better than conventional methods.<br>Based on the outcome of these surveys, future 3DVSP’s maybe acquired to help in developing the fields.