Field validation of imaging an adjacent borehole using scattered P-waves

Abstract

Acoustic waves enter a rock formation from a borehole and are reflected or scattered upon encountering a geologic structure. Consequently, we obtain the structure location represented by the azimuth and distance from the borehole using the acoustic reflection or scattering. Downhole acoustic measurements with the azimuthal resolution are realized using an azimuthal acoustic receiver sonde composed of several arcuate phased array receivers. Eight sensors distributed evenly across the arcuate phased array receiver can record acoustic waves independently; this allows us to adopt the beamforming method. We use a supporting logging tool to conduct the downhole test in two adjacent fluid-filled boreholes, for validating the evaluation of the geologic structure using scattered P-waves. The test results show the multi-azimuth images of the target borehole and the azimuthal variation in scattering amplitudes. Thus, we obtain the precise location of the target borehole. Furthermore, the measured values of the target borehole are consistent with the actual values, indicating that we can accurately evaluate a near-borehole geologic structure with scattered P-waves.

Geophysical exploration methods on bauxite reservoirs in L gasfield, Ordos Basin

“…The imaging logging series includes various logging methods such as acoustic wave, resistivity, nuclear magnetic resonance, etc., (Wang et al, 2022;Wang et al, 2021;Dan et al, 2019). At present, the development of imaging logging has been able to quantitatively evaluate fractures, identify pore structures, and evaluate fluid properties (Wang et al, 2023;Ben et al, 2020;Yang et al, 2019). This study further analyzes the pore structure and fluid properties of bauxite strata through electrical imaging porosity spectrum, conductivity spectrum, and apparent formation water resistivity distribution spectrum.…”

Unsupervised deep domain adaptation framework in remote acoustic time parametric imaging

“…compressional and Pseudo-Rayleigh waves) [5]. This imaging technology depends on the accurate analysis of the different mode structures and information extraction from weak signals [6][7][8]. In contrast, the piezoelectric pulse-echo rotating transducer, which scans strata and obtains structural information, is demonstrated as a succinct and low-cost scheme.…”