Industry response to the completed Williston Basin Lodgepole Source Rock and Oil Evaluation study of LSSI/Humble/Palacas (Joint Venture) has initiated this proposal for evaluation of the source rocks and oils of the Central Montana Trough. The study area covers the western portion of Montana, because the same mounds found in the Williston also crop out in western Montana (Bridger Range and Big Snowy Mountains) and are thought to occur elsewhere along the extent of the deeper water Central Montana Trough toward the Williston Basin.
Substantial hydrocarbon reserves have only been established in the Pennsylvanian Tyler and Amsden Formations in the vicinity of the Central Montana High and nearby anticlinal flextures. Although the Upper Mississippian Heath Fm. is the probable source for these oils, this conclusion is undocumented. Little is known concerning the quality and extent of potential deeper source rock intervals, and only a generalized Bakken distribution map is available to help assess where deeper potential reservoirs may be charged.
The following proposal by LSSI/Humble/Palacas (Joint Venture) is designed to evaluate the source potential of the sub-Heath statigraphic units in the Central Montana Trough. Limited analyses of the Heath source rock system (including the typing to Tyler/Amsden Oils) will establish a baseline to which the study analyses can be compared.
We will selectively sample the Heath, Lodgepole, Bakken, and Deeper Devonian and lower Paleozoic intervals in order to determine:
The total number of samples will be approximately 160 from up to 20 different wells. All samples will be described lithologically and analyzed for TOC/Rock-Eval* parameters. Approximately 60-75 samples will be assessed for vitrinite reflectance, thermal alteration index, and visual Kerogen composition to provide maturity profiles in the study area. Approximately 4 Paleozoic oils and 5 extracts from key source facies will be typed and characterized by GC, saturate and aromatic fraction carbon isotopes, and saturate fraction biomarker GC/MS analyses.
This study is still open at the early participant price of $19,500, upon completion the price will increase.
View the Evaluation Study Area Map for the Williston Basin
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