Herald Formation
The Herald Formation is a stratigraphical unit of Late Ordovician age in the Western Canadian Sedimentary Basin. It was defined in well Imperial Herald 1-31-1-20W2M by the Lower Paleozoic Names and Correlations Committee of the Saskatchewan Geological Society in 1958.[2] LithologyThe Herald Formation is composed of dolomitic limestone and dolomite, which can be microcrystalline, argillaceous or microlaminated. [1] In the centre of the basin, it is represented by anhydrite. DistributionThe Herald Formation reaches a maximum thickness of 38 metres (120 ft) in the Lake Alma area.[1] Relationship to other unitsThe Herald Formation is disconformably overlain by the Stony Mountain Formation and conformably overlays the Yeoman Formation.[1] It can be correlated with the Fort Garry Member of the Red River Formation in Manitoba and in the Williston Basin. SubdivisionsIn south-eastern Saskatchewan, the formation is divided in three units, corresponding to three sedimentation cycles: References
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