Integrated use of well data for structural control of seismic interpretation

Dipmeter data, core data, stratigraphic isochore data and seismic data provide the geologist with several different tools to obtain information on the orientation of bedding. When these data are integrated into a single database, the seismic interpreter can significantly improve the structural control of seismic interpretation by using all of the available information. In addition, any inconsistencies in orientation measurements from one or more data types are easily recognized, and the cause of the mismatch can be further examined. Experiences from the Gullfaks Field, northern North Sea, show that inconsistencies related to core data include non-optimal slabbing of cores, poorly developed bedding and misinterpreting sedimentary features as structural dip. Estimates of the orientation of bedding from stratigraphic isochore/isopach thickness estimates are poorly understood, or if repeated or missing sections related to faulting are not recognized. Bedding orientations from dipmeter data may be erroneous if the quality of the data are poor and the data points show significant scatter. Local variations in bedding orientation may be at a scale that will not be reflected in the seismic interpretation. In addition, in areas of poor seismic quality, seismic noise may interfere with real reflections and cause erroneous interpretation.