--> Abstract: Diagenesis, Reservoir Development and Hydrocarbon Charging in Sandstones of the Lower Cretaceous Mannville Group and Viking Formation in the Dodsland-Hoosier Area, West Central Saskatchewan, by Andy Tong, Per Kent Pedersen, and Guoxiang Chi; #90039 (2005)

Datapages, Inc.Print this page

Diagenesis, Reservoir Development and Hydrocarbon Charging in Sandstones of the Lower Cretaceous Mannville Group and Viking Formation in the Dodsland-Hoosier Area, West Central Saskatchewan

Andy Tong1, Per Kent Pedersen2, and Guoxiang Chi1
1 University of Regina, Regina, SK
2 Saskatchewan Industry and Resources, Regina, SK

Sandstones of the Viking Formation and Mannville Group in the Dodsland and Hoosier area, west central Saskatchewan, have produced in excess of 13.8 million m3 of oil and 750 000 e3m3 of gas. Previous studies have focused on sedimentology and stratigraphy. As such, little is known pertaining to diagenetic processes and their influences on reservoir quality, and the pressure and temperature conditions during hydrocarbon migration and reservoir charging. This paper reports on preliminary results on framework stratigraphy, petrographic studies of thin sections, microthermometric studies of fluid inclusions, and numerical modeling of basinal fluid flow.

Nonmarine and coastal facies of the Mannville Group strike northwest, whereas south prograding sand bodies of the Viking Formation strike east-west in the Dodsland-Hoosier area. Petrographic studies indicate sandstones of the Mannville Group are sublithwackes, while Viking sandstones are sublithwackes and sublitharenites. The sandstones are cemented by quartz overgrowths and carbonates to variable degrees. Porosity values based on point counting range from 1 to 22 percent. Sandstones with intensive bioturbation are generally of low porosity. Oil inclusions at a depth of 838.25m from a Mannville Group reservoir in the Hoosier area show an average homogenization temperature of 94.8°C. This high temperature indicates a heat anomaly during, and significant erosion after, hydrocarbon charging. Hydrocarbon migration may be related to topographic relief and / or overpressures produced by hydrocarbon generation, as numerical modeling indicates little compaction-induced fluid overpressure.

AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005