Identification and preliminary evaluation of source rocks within the Mississippian Madison Group: Williston Basin, North America

The Mississippian Madison Group has been the most oil productive conventional play interval of the Williston Basin with more than 4.6 billion BOE of cumulative production to date. Previously undocumented carbonate source rock intervals are observed in core and wireline logs within the upper Lodgepole/lower Tilston and lower Bluell stratigraphic sections. Both source rock intervals contain TOC values of 1–5%, plot as Type I/II (oil prone) kerogen signatures, reach upwards of 40+ feet gross thicknesses, extend laterally in the subsurface for 10’s of miles, and appear to be within the peak oil generation window (436–456° Tmax). Understanding the stratigraphic positioning, lateral extents, and hydrocarbon generation significance of petroleum source beds may be the key to unlocking one or more sets of unconventional resource plays within the Williston Basin.