FEATURES OF GEOPHYSICAL METHODS FOR STUDYING HYDRAULIC FRACTURE PARAMETERS IN VERTICAL AND DIRECTIONAL WELLS

Abstract

The paper presents a comprehensive systematic analysis of modern geophysical methods for evaluating hydraulic fracture parameters in vertical and deviated wells. The main existing approaches are reviewed, including well testing, microseismic monitoring, and a suite of production geophysics techniques: cross-dipole broadband acoustic logging (BAL), thermometry, radioactive tracers, and non-radioactive tagged (NRT) proppant technology. A comparative analysis of the information content and reliability of each method is conducted, highlighting their strengths and fundamental limitations. Particular attention is paid to the BAL method as the most widely used tool for assessing fracture height and azimuth. Based on the analysis of acoustic cement logging data, it is shown that the key criterion for reliable fracture height estimation using BAL is the quality of casing cementing. Examples of successful and unsuccessful BAL applications are provided, demonstrating the influence of cement sheath quality on result accuracy. Criteria for selecting candidate wells for such surveys are formulated, including requirements for deviation angle, cement bond quality, and sump depth. Practical recommendations are developed for planning measurements at different stages — before and after fracturing, in open and cased boreholes — which enhances the efficiency of diagnostics and calibration of geomechanical models.