AAPG HEDBERG CONFERENCE
"Mobile Shale Basins - Genesis, Evolution and Hydrocarbon Systems"
Shallow sediment mobilization in the northern North Sea
LØSETH, H., WENSAAS, L., SAWYER, D. E., ØKLAND, D. and JOHANNESEN, J.
Mounds and zones with a highly chaotic seismic
reflection pattern have repeatedly been observed in the Tertiary Hordaland
Within the chaotic reflection zones various types of anomalies are observed (V-brights, mounds, listric normal faults, undefined chaotic reflections)(Figure 1). Detailed 3D seismic interpretation combined with good well-calibration have improved our ability to discriminate between various seismic anomalies below the mounds. This paper will present ongoing work on identification of these anomalies.
J., Hay, S.J., Milne, J.K., Jebsen, C.,
H., Wensaas, L., Arntsen, B., and Hovland, M., 2003. Gas and Fluid Injection
Triggering Shallow Mud Mobilization in the Hordaland Group,
Figure 1. Typical seismic expression of the chaotic reflections, V-brights and mounds from the northern part of the Norwegian Block 30/9. Note the non-mobilized but polygonal faulted succession on the right part of the figure. (Modified from Løseth et al., 2003)
Figure 2. Schematic interpretation that indicate how the mobilized sediments reflect parts of the basin “plumbing” system. Hydrocarbons were generated in the Viking Graben and migrated vertical trough gas chimneys and sand injections and triggered the mobilization of the sediments in the Hordaland Group. The mobilization reflects two fluid systems, one sourced from Jurassic structures in the Viking Graben and a smaller eastern system sourced through intra Hordaland Group sands. (Modified from Løseth et al., 2003)
AAPG Search and Discovery Article #90057©2006 AAPG/GSTT Hedberg Conference, Port of Spain, Trinidad & Tobago