Chapter 24 Application of AVO analysis to seismic records on the Laptev Sea Shelf

Abstract

AbstractThe Laptev Sea shelf basin was affected by phases of Late Mesozoic–Cenozoic rifting and has a thick sedimentary complex associated with linear grabens and horsts, creating trends favourable for hydrocarbon generation. Two groups of complexes are identified in the sedimentary cover: syn-rift between seismic horizon A and LS4 and post-rift between seismic horizon LS4 and seabed. The syn-rift complexes include strata of Late Cretaceous, Paleocene, Eocene and Oligocene–Middle Miocene ages. The post-rift complex includes Pliocene–Quaternary strata. Six seismostratigraphic complexes are identified and traced in the area, using wave field's seismostratigraphic analysis. The boundaries of these complexes are represented by surfaces of unconformities. The wave field of the sedimentary cover contains reflections from gas-bearing sandstones with types 1 and 3 of AVO anomalies. A shift of the anomalies' features from type 3 towards type 1 occurs with increasing depth of the potential deposits in the section.