A LOGGING METHOD FOR LOCATING WATERED ZONE IN HORIZONTAL WELL WITH HIGH WATERCUT PROBLEM BY ISOTOPE LABELING

摘要

An isotope labeling testing method at a water outlet portion of a high water-cut horizontal well includes the following steps in sequence:a) solidifying isotopes from an isotope release device in a water-soluble carrier; b) connecting the isotope release device with an oil tube and lowering them to the horizontal segment of the well; c) dissolving and releasing the isotopes into water at the bottom of the well by the carrier , and the isotope release speed being proportional to the water flow rate; d) starting an oil production pump and beginning a production test; e) continuously performing gamma-ray spectrum analysis in produced water on the ground, and inverting the water outlet portion of the high water-cut horizontal well from the detected kinds and characteristic content of the isotopes. Because the isotope release device is conveyed through the oil tube, the method can overcome various restrictions of well trajectory and wellbore conditions, and reduce operating risks. The method can be completed during pump inspection, without the cooperation of a packer, a bridge plug, a downhole switch or other tools, the occupied time of a platform can be reduced, and accordingly reducing logging cost.