Is there a new understanding that explains why the Salina Basin in north-central Kansas is lacking in commercial petroleum production in contrast to the adjacent productive Forest City Basin?
The Salina Basin in north central Kansas and the Forest City Basin in north eastern Kansas are two adjacent sedimentary basins, separated from each other by the Nemaha Ridge, with the former basin being to the west of the ridge and the latter to the east of the ridge. The two basins are very similar in their depositional and burial histories. The contrast between the two basins, with hardly any significant oil accumulation in the Salina Basin while the adjacent Forest City Basin is productive, is remarkable and has presented a challenge for a rational explanation. This contrast could provide a clue to the origin of petroleum in Kansas. Early studies postulated distant organic sources from the deeply buried Anadarko Basin in Oklahoma. The presence of ‘a shadow zone’ disrupted long migrations of oils from the south that prevented the Salina Basin from becoming productive, but allowed migration into the Forest City basin. Two recent works contest this concept of long distance migration from Oklahoma for oils in northern Kansas (Newell and Hatch, 2000; McIntire et al. 2014) and suggest that oils in northern Kansas were locally derived. We suggest a model that emphasizes five critical elements that include water (hydrosphere), gas (atmosphere), organic matter (biosphere), mineral matrices (lithosphere), and energy (ergosphere) for generation of oils in source shale rocks. We postulate that water in an unfavorable state prevented the generation of oil in the Salina Basin.
AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015