Kirk A. Wagenvelt, Dave Barnes, Michelle A. Kominz, and Josh Samson
Western Michigan University, Kalamazoo, MI
Large volumes of historic hydrocarbon production in the Michigan basin indicate the presence of major deposits of organic compound (Corg)-rich rock strata. Geologic processes that control the generation of hydrocarbon deposits are biodegradation (near surface) and heating of the Corg in source rocks by geothermal processes, normally associated with gradual, sedimentary basin subsidence and burial to significant depth in the subsurface. The Michigan Basin experienced long-lived subsidence during the Paleozoic Era with the base of the sedimentary succession now at ~5000 m. After over 100 years of commercial hydrocarbon production in the basin, the geologic controls on time-temperature dependent thermo-maturation of commercial hydrocarbons from Corg -rich source rock strata remain unclear. Previous studies have observed anomalous thermal maturity of Corg -rich strata in the Michigan basin. More recent work has pointed to the Mid-Continent Rift system as a possible locus for most anomalous thermal maturity measurements. A detailed study is currently underway to better document the spatial distribution of anomalous thermal maturity.
Maps were plotted to determine the spatial distribution of available thermal maturation data in the Michigan basin. The data are sourced from published data and newly released (from proprietary hold) analytical data generated by industry sampling of curated rock samples. The combination of the data sets provides a more comprehensive view of the spatial distribution of thermal anomalies associated with Corg-rich strata and possible insight to the origin of accelerated maturation although additional sampling may be needed to document the influence of the deeply buried Mid- Continent Rift on thermal alteration.
AAPG Search and Discovery Article #90181©2013 AAPG/SEG Rocky Mountain Rendezvous, University of Wyoming, Laramie, Wyoming, September 27-30, 2013