Key Technologies for Drilling Horizontal Wells in Glutenite Tight Oil Reservoirs in the Mahu Oilfield of Xinjiang
The Mahu tight glutenite oilfield in the Junggar Basin is the key area for increasing production in Xinjiang Oilfield. In order to meet the needs of exploration and development in this oilfield, improve the drilling speed and to shorten the drilling cycle, the key drilling technologies suitable for the efficient development of horizontal wells in the Mahu tight glutenite oilfield was developed by several means. The technologies included optimizing the designs of the casing program and wellbore trajectory, selecting the drilling fluid, customizing the PDC bit properly, adopting a series of drilling speed-up technologies, including the ductile cement slurry, floating casing and cementing, PDM+ PDC bit compound drilling and rotary steering drilling, etc. In 2018, this oilfield has completed eight horizontal wells in tight sand conglomerate in Ma131 Block, with the average well depth of 4 921.75 m, average horizontal section length of 1 576.00 m, average drilling cycle of 46.5 d, and average ROP of 11.19 m/h. Among them, the Well MaHW1247 has the total depth of 5040 m and drilling cycle of only 42 days, it has set the fastest drilling record in the horizontal wells with a total depth of more than 5 000.00 m in the Mahu Oilfield. The field applications demonstrated that the key technologies could effectively improve the ROP and shorten the drilling cycle, and provide technical support for the exploration and development of Mahu Oilfield.
2019 AAPG Datapages/Search and Discovery Article #130007 © 2019 Petroleum Drilling Techniques, Issue 2, 2019