About This Item
Share This Item
Trend-surface analysis of structure on the Cretaceous Fish Scales marker horizon indicates the presence of underlying Leduc (Devonian) reef bodies in deeply-buried strata adjacent to the Foothills belt. Included are reef bodies associated with Windfall, Pine Creek, Bigstone, Simonette, and Sturgeon Lake fields. Results of this analysis have exploration significance because of sparse well control for deep Devonian strata and the availability of more widespread data from shallower drilling. Several anomalies shown by the analysis indicate the possible presence of undrilled Leduc reefs.
Success with this technique depends greatly on careful stratigraphic correlation of the higher beds as the anomalies are commonly very subtle. For example, the third-order residual map which best defines the Leduc reefs represents only 0.29% of the total map variability. The present study used data from 776 wells evenly distributed across about 33,000 sq mi; maximum well density was 3 wells per township (36 sq mi). Other geologic features revealed by the analysis include low-displacement normal faults and, apparently major depositional trends in the Beaverhill Lake and Woodbend (Devonian) intervals.
End_of_Article - Last_Page 839------------