One of the major structural elements of South Vietnam offshore is Mekong depression in the shape of asymmetrical fault trough. The depression is limited by Con Son uplift zone from the South and Southeast, and links with it by the regional fault of the Northeast trend. North-westward, the trend merge into monocline, conjugated with Soc Trang uplift of northeast trend. Eastward, the zone of outer uplifts is located, while westward – Khorat-Natuna uplift zone.
The authors summarised the data on implemented drilling techniques and bottom-hole assemblies, drilling practices and bit runs. We analysed the types and performance of bits for the certain intervals of structural cross-section, conclusions drawn on the most optimal and effective types of drilling bits. We provided recommendations on application of drilling muds and cement slurries, as well as on well cementing technology. The results and technology of well tests by foreign companies are analysed. A variety of disadvantages in technology tests are defined. We summarized the data, studied variation behaviour of reservoir pressures and temperatures along the cross-section, and obtained data on reservoir properties and well productivity. A preliminary processing of tests data is performed for the second zone of well 5-BT of White Tiger field. Some conclusions are made and recommendations on well testing are given.
The article covers the analysis of drilling techniques and technologies, as well as the tests of wells, drilled by foreign companies in Vietnam offshore during 1974-1980. We characterized the geological factor of drilling and analysed the related complications, which occur during the drilling process. Recommendations on preventing such complications during well construction on the new structures are provided.
It is shown, compilation, study and analysis of exploratory drilling experience at Vietnam offshore, in terms of technical-historical aspect, is important and may contribute into development of drilling and oil production on other offshore oil fields.
References
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2. Dergunov E.N., Khoy N.D., Barothermal conditions of oil and gas reservoirs in exploration work on the shelf of southern Vietnam (In Russ.), Neftʹ i gaz, 1983, no. 4, pp. 27–35.
3. Tu Than Nghia, Veliev M.M., Ivanov A.N. et al., The history of prospecting and exploration for oil and gas on the continental shelf of South of Vietnam (In Russ.), Neftyanoe khozyaystvo = Oil Industry, 2017, no. 8, pp. 10–14.
