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January 16th, 2019 11:30 AM - 1:00 PM


January 16, 2019


SPEAKER:  John B. Curtis, GeoMark Research, Ltd. And

Colorado School of Mines   


Petroleum Geochemistry of Woodford-Sources Oils from the Mid-Continent Region, USA



10 NW 6th Street



WEDNESDAY January 16, 2019

LUNCH 11:30am – 1:00pm





330 crude oils from Oklahoma, Kansas, and Nebraska, with biomarker and carbon isotope values characteristic of UD-LM Woodford Shale source rocks were assessed using cluster and principal component analyses. These oils have relatively depleted carbon isotope compositions, strong upwelling signatures, profuse green algae input, and abundant isorenieratanes, biomarkers for extremely anoxic conditions in shallow water (Photic Zone

Euxinia). The oil reservoirs range from Cambrian to Cretaceous.

Five oil families were identified, their geographic occurrences mapped and probable source facies interpreted. Family 1 oils only occur in Kansas and Nebraska, from the Sedgwick Basin NW along the NE side of the Central Kansas Uplift. Long range migration of Family 1 oils to the NW into Nebraska appears to have occurred along the NE flank of

the Central Kansas Uplift. Oil Families 2, 3, and 4 were likely generated from different vertical organofacies of the Woodford; Family 5 oils appear to have been sourced from the UM Caney Fm. Family 4 oils are produced in Oklahoma and Kansas, but not Nebraska. Family 4 oils originated in the Anadarko and Arkoma basins, with long-range migration in two directions: 1) NNW from the Anadarko Basin, west of the Nemaha Uplift, into Kansas along the SW flank of the Central Kansas Uplift; 2) NNE from the Arkoma Basin along the

Cherokee Platform, east of the Nemaha Uplift, reaching Vernon Co., Missouri and the Forest City Basin. Horizontal Woodford completions in the STACK play are members of this family. Family 3 has the most positive carbon isotopes, the lowest upwelling signatures, and the highest paralic indications. These oils occur in distinct regions with apparent migration trends: 1) In a northerly direction from north-central Oklahoma into eastern-central Kansas and the Salina Basin along, and on the western flank of the Nemaha Uplift; 2)

In a NE direction within the Hugoton Embayment of SW Kansas, from mature Woodford sources in the Anadarko Basin of the Oklahoma and Texas panhandles.

Maturity-dependent oil biomarker ratios were evaluated to calculate a vitrinite reflectance equivalent (%VRE) for each

oil. The range in oil thermal maturity (related to source rock maturity at the time of expulsion) is from <0.7% VRE to >0.9% VRE. Only Family 3 & 4 oils are at levels which are generally best suited for unconventional production (>0.85% VRE).


John B. Curtis has worked with GeoMark Research in various capacities since 1996. He is currently responsible for their U.S. and Canadian Rocky Mountain and SCOOP/STACK petroleum system/resource potential studies. He received a B.A. (1970) and M.Sc. (1972) in geology from Miami University and a Ph.D. (1989) in geology from The Ohio State University. He is a licensed Professional Geologist (Wyoming). Curtis was a Minuteman Missile Launch Officer and Instructor Launch Officer in the United States Air Force from 1972-1975.

 Dr. Curtis is also Professor Emeritus of Geology and Geological Engineering and past Director, Potential Gas Agency at the Colorado School of Mines (CSM).  He was Associate and then Full Professor at CSM from July 1990 until his retirement in June 2016. While at Mines, he supervised graduate student research and taught petroleum geology, petroleum geochemistry and petroleum design. He had 15 years prior experience in the petroleum industry with Texaco, SAIC, Columbia Gas, and Brown & Ruth Laboratories/Baker-Hughes. He served on and chaired several professional society and natural gas industry committees, which included the Supply Panel, Research Coordination Council, and the Science and Technology Committee of the Gas Technology Institute (Gas Research Institute). Curtis co-chaired the American Association of Petroleum Geologists (AAPG) Committee on Unconventional Petroleum Systems from 1999-2004 and was an invited member of the Interstate Oil and Gas Compact Commission and the AAPG Committee on Resource Evaluation from 1992 until 2014. He was a Counselor to the Rocky Mountain Association of Geologists from 2002-2004 and RMAG delegate to AAPG for nine years.


Dr. Curtis was an Associate Editor of the AAPG Bulletin from 1997 – 2010 and continues to review manuscripts for several journals. He has published studies and given numerous invited talks concerning source rock and oil geochemistry, exploration for unconventional reservoirs, and the size and distribution of U.S., and Canadian natural gas resources and comparisons of resource assessment methodologies. As Director of the CSM Potential Gas Agency from 1991 - 2016, he directed a team of 100 volunteer geologists, geophysicists and petroleum engineers for the Potential Gas Committee’s biennial assessment of remaining U.S. natural gas resources.


Attendance without reservation will not be possible.  Reservations must be cancelled by January 11, 2019 at noon to avoid being charged.  Thank you for your consideration.


NOTE: Please make sure your OCGS dues are paid before registering!! 
To double check if you are paid, please email Chelsey @ [email protected]