On June 9, China's offshore giant carbonate buried hill reservoir development project, Weizhou 5-3 oilfield was put into operation, marking China's new progress in the field of offshore carbonate buried hill development, injecting strong momentum into China's marine energy development.

China is rich in carbonate oil and gas resources, and has great potential for exploration and development. As one of the major categories of unconventional oil and gas reservoir research, it has become an important field of oil and gas exploration and development and oil and gas reserve and production increase in China. Weizhou 5-3 Oilfield is an offshore buried hill fractured carbonate reservoir, which has challenges such as multiple solutions in geological models and difficult reserve evaluation due to its complex lithology and strong reservoir heterogeneity.

The project is located in the Beibu Gulf basin of the South China Sea, with an average water depth of about 35 meters, and the main production facilities include one self-installed wellhead platform, which is developed based on the existing facilities in the surrounding area. It is planned to put into operation 10 development wells, including 7 production wells, 2 water injection wells and 1 gas injection well. It is expected to achieve peak production of approximately 10,000 barrels of oil equivalent per day in 2026 with a medium crude oil nature.

The project team established a geological model of carbonate paleoburied hills by combing the historical context of tectonic-sedimentary-diagenesis-thermal evolution, consolidating the analytical and laboratory results of exploratory wells, and combining the genesis mechanism and development law of fractures in multiple disciplines. In terms of research methods, technologies such as multi-scale fracture carving, high-precision seismic imaging and fluid identification of carbonate rocks have been successively overcome to realize the effective identification and prediction of fracture distribution.

The Weizhou 5-3 oilfield development project is located in the Beibu Gulf Basin. The project has carried out adaptive upgrading and transformation of the self-installed wellhead platform "Offshore Oil 165", and effectively met the operation needs of 10 wells by adding facilities with oil and gas treatment and other functions. In addition, the project will build a 24-kilometer submarine mixed pipeline and 5.5 kilometers of submarine cables, and renovate three existing platforms in Weizhou.

The 12/16-inch double-layer insulated submarine pipeline from Weizhou 5-3WHPA platform to Weizhou 12-1WHPC platform will become the aorta pipeline in the western area of Weizhou Oilfield, providing important infrastructure support for the improvement of regional oil and gas production capacity.

The project plans to put into operation a total of 10 development wells, including 7 production wells, 2 water injection wells and 1 gas injection well, and is expected to achieve peak production of about 10,000 barrels of oil equivalent per day in 2026. The project provides strong support for improving China's offshore oil and gas self-sufficiency, and has also accumulated valuable experience for the development of similar projects.(This article is from the official website of Seetao www.seetao.com. Reprinting without permission is strictly prohibited. Please indicate Seetao.com + original link when reprinting) Seetao.com Strategy Column Editor/Sun Fengjuan