DOI: 10.24412/2076-6785-2021-1-34-39
Abstract
The article presents the results of investigations of the causes of total and catastrophic losses of drilling mud during drilling of wells in the reef massif of the Western dome of the Yuzhno-Orlovskoye oil field. The regularities of the distribution of intervals of mud losses of different intensity in a single buried reef of the Upper Frasnian and Famenno-Tournaisian times have been established. It is noted that total and catastrophic losses in a single buried reef are confined to the zones of the pre-reef plume, consisting of detrital carbonate rocks. Partial losses occur in the intervals of cavernous-fractured carbonate reservoirs of organogenic structure. The absence or insignificant absorptions are the features of carbonates of the bioherm core of the buried reef. It is shown that the development of a geomechanical model of an organogenic structure based on the features of the lithologic and facies zones of the reef massif makes it possible to increase the accuracy of predicting the zones of absorption during well construction designing. The research results show that the system analysis and generalization of theoretical and field geological, geophysical and technical information allows to determine the nature of losses of drilling mud in organogenic structures, to predict the zones of possible problemms and to develop effective measures for their timely prevention and elimination during well drilling at the Kama-Kinel downfold system fields.
Material and methods
Survey made by gathering, review and collation of the theoretical and field data to determine patterns of the loss zones throughout reefal buildup.
Keywords
well drilling, absorption of drilling mud, organogenic buildup, single buried reefs, reef massif, depression zone, Kama-Kinel downfold system
