< Back to Calendar

FREE Virtual Luncheon- Craig Barrie (GeoMark)

May 20th, 2020 12:00 PM - 1:00 PM

Best Practices For Understanding Fluid Contributions in Unconventional Resource Plays

Craig D. Barrie*, Catherine M. Donohue, J. Alex Zumberge & John Zumberge

GeoMark Research, 9748 Whithorn Drive, Houston, TX, USA

The term ‘Production Allocation’ has a very specific meaning and utility in conventional resource plays. The geochemical characteristics which underpin this method are relatively straightforward and have been used to great success in conventional systems over the last several decades. With the rise of unconventional resource plays, particularly in the USA, and fluid production from primarily self-sourced lateral target zones, the potential for ‘Production Allocation’ to be applied to these plays was evident. An early approach suggested that individual target zones could be separated geochemically using extracted core fluids, allowing original ‘end-member’ signatures to be defined. This would then allow the production fluids to have their contributions allocated back to extract defined production zones. However, as a number of studies have reported, unconventional resource plays do not host discrete production compartments. Rocks and subsequent solvent extracts from lateral cores reveal the natural lateral and stratigraphic geochemical variability of source and reservoired hydrocarbons. Furthermore, while the availability of relevant core material is useful, it is not essential, in order to attempt to assign allocation contributions.

In this talk we will outline a robust approach, with associated case studies, to help understand and interpret geochemical data from unconventional systems in the context of their natural variability. This work will demonstrate the difference between hydrocarbon extracts that are identified as potential production contributors versus those with a unique fingerprint, but not representative of a significant contributor to production. Furthermore, emphasis will be placed on the utility of the production fluids themselves and their importance for appropriately understanding and recognizing distinct fluid compartments and statistically significant variability and mixing.   Hierarchical cluster analysis and principle component analysis methods are used to determine geochemical relationship of the produced oils while Alternate Least Squares are used for allocation of samples after appropriate ‘end-member’ definition. 

The overall objective of this talk is to emphasize what information and level of detail can be reliably ascertained from ‘allocation’ projects in unconventional plays. At a minimum these projects should assist operators in determining if production is from the target interval itself or if fluids are being drawn in from zones above/below the target interval and how this relationship changes through production.




Dr. Barrie graduated from the University of Glasgow, Scotland in 2005 with a 1st class honours degree in Geology, following this up with a Ph.D. in Mineralogy and Geochemistry from the University of Liverpool, England in 2008. During his initial post-doctoral career Dr. Barrie specialized in sulfide mineralogy and advanced microscopy and stable isotope techniques during teaching and research positions at the University of St. Andrews and the Scottish Universities Environmental Research Center. Prior to joining GeoMark Research in 2015, Dr. Barrie worked for an isotope ratio mass spectrometer manufacturer, providing technical and application support for clients across the globe.

Dr. Barrie is a Senior Geochemist with GeoMark Research and is the team lead for ‘Reservoir Geochemistry’. His role at GeoMark research primarily involves the design, implementation and interpretation of geochemical projects for clients. In addition Dr. Barrie undertakes research collaborations with various Universities in North America and further afield and has published more than 30 papers on a range of sample types and study areas, from environmental and paleoclimate projects through metallic ore resources and petroleum source characterization.