First Break - Volume 13, Issue 10, 1995

The Central Graben of the Five Countries Area (Fig. I) has been extensively studied and is a major hydrocarbon province of the North Sea. However, geological reviews have tended to be confined to one particular country. This articIe, derived from an integrated geophysical/geological study (Count Geophysics Ltd & Halliburton RDS 1993), is a brief review of the structural styles and features, disregarding national boundaries.

The improved data quality offered by modern seismic surveys has permitted much more confident interpretation of subsurface geology. Nevertheless, seismic interpretation remains problematic in areas of complex salt teetonics or volcanics. Despite greatly improved seismic acquisition and processing methods, the presence of out-of-plane reflections and limited acoustic impedance contrast between salt and compacted sedimentary rocks may make interpretation of deep salt structures difficult, especially in areas where 30 seismic are not yet available.