Abstract:
With the goal of solving the problem of circulation lost under complicated geological conditions of the Tarim Oilfield, this paper analyzed the types of circulation lost in this oilfield combining its formation characteristics, and summarized the development history and achievements of leakage prevention and plugging technologies in this field. It shows that leakages induced by porosity, fracture and caverns are all encountered in Tarim Oilfield, but mainly caused by fractures and cavity. The development of leakage prevention and plugging technologies in this oilfield has undergone two stages: the establishment of basic system and the development and perfection of characteristic technology. A series of techniques have been formed such as oil-based drilling fluid leakage prevention and plugging, high-strength pressure-bearing plugging, high-pressure brine layer leakage prevention and plugging, and fracture-cavity leakage plugging. From the analysis and sorting, we have clarified the current status of leakage prevention and plugging techniques in Tarim Oilfield and the remaining challenges in leakage control, and determined the trend of research. We proposed suggestions for further development of those technologies, such as strengthening formation prediction, developing or introducing new plugging technologies, enriching engineering techniques, and developing big data plugging software.