Moustapha El-Baz¹
(1) Albaz Geological Consulting, Calgary, AB

Abstract: Mc Murray Formation reciprocal of sedimentation and its impact on hydrocarbon accumulations, Surmont field, NE Alberta

Mc Murray Formation is bitumen; gas and water bearings with ranged thickness between 38 and 105 m. in Surmont field.Thickness and depositional facies of selected intervals in these successions vary significantly. Hydrocarbon-water contacts exhibit a significant high irregularity. Alternate juxtaposition of thick-to-thin correlations suggests that reciprocal sedimentation played a crucial role. Lower McMurray was formed by fluvial flood plain environment that developed between the high topographic relief of the Devonian hills, while the middle member composed of massive sandy facies deposited by channel incision in estuarine environments. The upper unit was deposited in transition zone between a series of bars and interbar troughs and nearby estuary. These sequences were followed later by the regional progradation massive Clearwater formation marine shales. A petrophysical model has been applied to identify these reservoir zonation boundaries and differentiate between the marine and non-marine environments. Composite log has been created to show Mc Murray members subdivision. Hydrocarbon Water contact controversial can be solved and interpreted by incised valley model. This model is mainly supported by the structure framework (Salt collapse due to salt dissolution of Muskeg Formation) and high intensive lateral accretion of migrated channels incised in estuarine setting.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana