Full text loading...
-
The Nature of The Anomalous Seismic Pattern of Reflector B in The Classical Structure of The Bazhenov Formation on The Eastern Framing of The Surgut Arch
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, EAGE/SPE Workshop on Shale Science 2021, Apr 2021, Volume 2021, p.1 - 5
Abstract
Summary
This paper discusses one of the variations in the structure of the classical type of section of the Bazhenov Formation, which has a non-standard expression on seismic sections. The geophysical expression of such sections is similar to the pattern inherent in the anomalous sections of the Bazhenov Formation: the negative phase of reflector B expands, the negative phase is locally bifurcated, and an independent lenticular positive reflection appears inside. In the zone of bifurcation of the negative phase of reflector B in the well sections, an increased thickness of the Formation is noted, namely, its upper part of the section - 6th band. With a sufficient thickness of 6th band, a two-modal high-amplitude negative reflection is formed due to the change in acoustic properties, first when passing from the Lower Achimov clays to clay silicites of the 6th band and further to silicites composing bands 1–5. The well data demonstrate that the Bazhenov Formation is laterally sustained within this zone. Changes in thickness are relatively smoothly, according with the structural-tectonic plan of the territory. Such a structure of the Formation is due to the redistribution of sedimentary material of 6th band into accommodation spaces on the slope of the Surgut arch.
© EAGE Publications BV