High-Resolution Seismic Imaging and Modeling of Structural and Stratigraphical Features in the Southwest Barents Sea
Abstract
High-resolution P-Cable and conventional 3D seismic data have been used to image and map shallow structural
and stratigraphic features in the Hoop area, SW Barents Sea. The gap in resolution between the P-Cable and
conventional seismic data has been addressed by synthetic seismic modelling, partly motivated by outcrop
information. The seismic modelling shed light on the resolution allowed by seismic data; combined with detailed
observations in the P-Cable data, improved confidence in the interpretation of the conventional seismic data can
be achieved. Synthetic seismic data based on conceptual fault geometries inspired by field observations are
compared to real seismic data. A wide range of frequencies are tested in the seismic modelling to demonstrate
the differences in resolution, which thus determine minimum scales for identifiable sedimentary features and
faults in the subsurface. The P-Cable data typically have resolution of 4-7 m in the shallow subsurface, up to four
times better than in conventional data. The high-resolution P-Cable seismic data thus reveal complex
stratigraphic and structural features, such as small-scale clinoforms and smaller faults. The Lower Cretaceous
delta succession belongs to a large delta and shelf system that prograded from NW into the study area during the
Barremian. The seismic data image characteristic clinoforms at various scales making it possible to map
architecture and thus constrain depositional environments in some cases. The large-scale clinoforms typically
have heights of 150-200 m and dips of 0.65-1.13° after correcting for compaction related to 2150 m deeper
maximum burial before Cenozoic uplift and erosion. The Lower Cretaceous delta and shelf succession from NW
in the study area is faulted, and thus the main Early Cretaceous fault activity post-dates the Barremian arrival of
the delta. Detailed ties to wells with biostratigraphic age data, reveal an Aptian?-early Albian age of the main
faulting event. Faulting likely initiated in the Aptian but a hiatus/condensed section makes it difficult to constrain
the exact onset of offset. Combining the new constraints on the faulting in the Hoop area with similar structures
observed in the neighbouring Fingerdjupet Subbasin document a significant Early Cretaceous extensional event
causing subsidence in a broad NNE trending basin province and a transgressional system reaching Svalbard in
Albian time.
AAPG Datapages/Search and Discovery Article #90350 © 2019 AAPG Annual Convention and Exhibition, San Antonio, Texas, May 19-22, 2019