Место издания: Геленджик , Год издания: 2021

The work deals with the substantiation of a new geophysical technology for mapping the Bazhenov Formation through borehole pulsed electromagnetic sounding. We theoretically showed its applicability to the study of the formation from highly deviated and sub-horizontal wells penetrated the Lower Cretaceous, Upper and Middle Jurassic deposits. Numerical simulation of the signals was carried out via the example of the East Surgut field for realistic geoelectric models of the Bazhenov Formation with real well paths. We established that spatial locations of the top and bottom of the layers can be identified during both well logging and cross-well exploration. Areas of high sensitivity of the measured signals to the Bazhenov Formation boundaries were appraised as function of the emf registration time and distance between the electromagnetic field source and receiver. The calculations indicate that the pulsed sounding of the Bazhenov Formation from the Upper and Middle Jurassic reservoirs is achievable for mapping the formation boundaries as well as tracking its lateral variability. The use of systems of vertical and horizontal wells drilled in the overlying and underlying target objects reveals a high potential of the proposed method in respect to cross-well exploration. The performed research significantly expands the capabilities of pulsed electromagnetic sounding as applied to oilfield geophysics.