Study On Logging Method And Technology Experiments Of Underground Elevation Boreholes

Downhole usually adopts the drillings to track and localize coal seam, limited by the construction technology, the effect of drilling trajectory and target horizon control is not ideal, especially in the test of elevation borehole, for the sake of contact conditions, most methods (such as the self-potential and apparent resistivity, etc.) are difficult to be applied, therefore, it is necessary to research and improve coal seam elevation borehole positioning test techniques.On the base of the common and mature ground logging technology, paper combined track test with natural gamma ray, and applied it to the downhole drilling elevation in the test. To improve the existing ground logging equipment, paper developed a set of mine elevation test device firstly; Secondly, compared the system with ground testing equipment and other testing technique, the average error test showed that the space positioning accuracy of the system is high; Lastly, combining projects of Huainan Mining Group, completed the downhole elevation and down hole testing, the results showed that the system is accuracy in borehole trajectory determination, the collecting ability of the rock of natural gamma ray signal is also strong, the combination of coal seam tracing positioning is accuracy.The main innovation of paper embodied in two points:completed downhole elevation drilling test equipment research and development; combined trajectories with natural gamma logging method in the elevation drilling and formatted one set of mature testing methods. At present, the test device and method is still at the stage of experimental research, affected by test conditions and time limit, the paper just completed the natural gamma ray parameters testing, resistivity logging and other methods should be combined into actual elevation borehole trajectory measurement and distinguishing the coal strata of roof problems still need further perfect.