USE OF LOW-FREQUENCY SEISMIC PROBING METHOD FOR DETERMINATION OF WELL LOCATION COORDINATES FOR DRILLING

Abstract

A wide range of studies, including structural and tectonic, lithological and facies, geochemical, hydrogeological, and geophysical methods, are carried out during the development of fields at the regional stage of geological exploration. These studies are aimed at solving key problems, such as identifying lithological and stratigraphic complexes, determining the main stages of geotectonic development, and identifying promising oil and gas complexes.However, despite the extensive studies performed, they do not always provide a final confirmation of the presence or absence of oil deposits. In recent years, in order to more accurately determine the location of oil fields, the method of low-frequency passive seismic sensing (LPDS) has attracted attention.This article discusses two hypotheses that explain the causes of anomalies in the spectrum of microseismic signals over oil and gas reservoirs. The first hypothesis assumes that during harmonic seismic excitation, the deposit goes into a state of «turbulent chaos», leading to a change in the characteristics of the seismic signal. The second hypothesis states that a change in the velocity of propagation of seismic waves in the porous environment of the deposit also causes anomalies in the signal spectrum.Experimental data support both hypotheses, and represent anomalies in the spectrum of microseismic signals in the frequency range of 2-5 Hz. Understanding these anomalies is essential for improving oil and gas discovery and evaluation techniques, contributing to more efficient development of oil and gas resources and improving accuracy of well coordinates