关键词: 非常规, 页岩气, 取心, 机械钻速, 龙马溪组, 牛蹄塘组

Abstract:

During the drilling process of the shale gas wells, obtaining the high quality core samples is an important prerequisite for the reservoir evaluation. Aiming at the problems such as the long coring footage, the low core recovery and the poor efficiency of the conventional coring technology, and based on the analysis of the geological characteristics of the coring layer, we optimized and improved the tools, the bit, the parameters and the technology. In the field application of the multiple shale gas wells, the average core recovery was more than 98 % and the penetration rate was up to 9 m/h. The results showed that this technology had wonderful performance in improving the core recovery and the penetration rate, and successfully resolved the various problems in the process of the coring in the shale gas wells. In the meantime it provided important support for the later development of the shale gas wells.

Key words: unconventional, shale gas, coring, penetration rate, Longmaxi formation, Niutitang formation