ABSTRACT: Submarine Fan "Lobe" Models: Implications for Reservoir Properties

G. Shanmugam, R. J. Moiola

A multitude of submarine fan "lobe" models, advocating widely different reservoir properties, has been introduced into the sedimentologic literature. Four of these models are compared to show their differences in reservoir properties. Braided suprafan lobes are characterized by stacked sand bodies with good lateral and vertical communication, and they constitute excellent reservoir facies. The unchanneled depositional lobes, composed of sheetlike sand bodies with good lateral and moderate vertical communication, exhibit properties of good reservoir facies. Fanlobes, which refer to meandering channels and associated levee facies of large mud-rich submarine fans such as the Mississippi Fan in the Gulf of Mexico, are characterized by offset stacked sand bodies with poor late al and vertical communication. These lenticular sands have the potential to be moderately good reservoir facies. Ponded lobes, which represent mud-rich slump facies of slope environments, comprise poor reservoir facies because of poor sand content and poor sand-body connectivity caused by chaotic bedding. Furthermore, the presence of slumped mud layers in ponded lobes is expected to hinder fluid flow. Because different "lobe" models vary significantly from one another in terms of reservoir properties, caution must be exercised to apply the proper "lobe" model to ancient fan sequences in hydrocarbon exploration and production.

AAPG Search and Discovery Article #90999©1990 GCAGS and Gulf Coast Section SEPM Meeting, Lafayette, Louisiana, October 17-19, 1990