Difficulties and countermeasures of Carboniferous shale gas drilling engineering in western Guizhou
Due to the complex geological conditions in the Carboniferous of western Guizhou,many risks and difficulties in drilling engineering pose great challenges to drilling work.Based on the geological data obtained in the region and combined with the practice of drilling engineering of several shale gas wells in the region,difficulties of drilling engineering in the region have been summarized as follows.Serious drilling lost circulation due to the development of shallow karst caves and fractures,the wellbore of shale section of the target layer of Dawuba Formation is prone to collapse and instability,gas layer and fracture development layer coexist,some areas contain hydrogen sulfide and the risk of safe drilling is high.To address the above difficulties,technologies or methods such as engineering-geophysical exploration of shallow karst cave before drilling,"three spud"optimization design of casing program,selection of preferred drilling equipment,and fast and efficient drilling were proposed.Finally,it is suggested to conduct research on the coupling mechanism of"lost circulation,well kick,and collapse"to form an adaptive engineering technology system in western Guizhou in order to provide technical support for achieving efficient exploration and development of shale gas in this area.
shale gaslost circulationwellbore stabilitycasing programdrilling with casingCarboniferous
万方数据
维普
