METHOD FOR DETERMINING SPATIAL ORIENTATION OF FRACTURE OF HYDRAULIC FRACTURING IN HORIZONTAL WELLBORE

摘要

FIELD: mining.;SUBSTANCE: invention relates to hydraulic fracturing (HF) and can be used to determine the orientation of a fracture in a horizontal wellbore resulting from HF. Method includes carrying out HF with formation of the fracture and the determining spatial orientation of the fracture before and after the HF by a geophysical method by running a geophysical device on the column of pipes into the perforation interval of the formation to be fractured. Prior to the HF operation in the horizontal wellbore in the interval of cased hole perforation or the barrel interval, through which the HF is planned, geophysical method is used to perform neutron-neutron logging by thermal neutrons – NNL-T (1), then a proppant HF is performed using a crosslinked fracturing fluid using borate crosslinks, after the HF, the process is held until the pressure drops to zero, then by swabbing, fluid is withdrawn from the well in a volume (V_o): V_o=k⋅V_h, where V_h – volume of helium liquid used for HF, m³; k is the conversion factor, k = 0.1, further replace the liquid in the well with a liquid with a density equal to the density of the liquid during the first NNL-T (1), then repeat neutron-neutron logging with thermal neutrons – NNL-T (2) using the same geophysical device and at the same velocity of passage in the trunk of a horizontal well in the interval of the hydraulic fracturing, compare the records of the NNL-T (1) with the recording of the NNL-T (2) in the interval of the HF and determine the spatial orientation of the fracture in the horizontal wellbore, if the length of the section with the distortion of the recording of NNL-T (2) after the HF is L₂' relative to the length of the record of NNL-T (1) before the HF – L₁ and if L₂'=L₁ with a deviation of up to 2 m, the HF fracture is oriented along the horizontal wellbore, if L₂''≤0.5⋅L₁, the HF fracture is oriented at an angle of 30÷60° relative to the horizontal wellbore, if L₂'''≤0.25⋅L₁, the fracture is oriented at an angle of 60+90° relative to the horizontal wellbore.;EFFECT: technical result consists in increasing the efficiency of determining the direction of the spatial orientation of the fracture in the horizontal wellbore.;1 cl, 4 dwg