Date(s) - 11/12/2019
11:30 am - 1:00 pm
Utility of Reservoir Geochemistry in Unconventional Plays: A Case Study from the Delaware Basin
Craig D. Barrie*, Catherine Donohue and J. Alex Zumberge
GeoMark Research, Houston, TX, USA
The rapid expansion of unconventional petroleum exploitation over the last 5 years has resulted in the development and growth of ‘production allocation’ and ‘time lapse’ geochemistry (TLG). This field can be broadly seen as ‘unconventional’ reservoir geochemistry and is an adaptation of well-established conventional reservoir ‘allocation’ studies. However, geologic context is important and unconventional systems throw up a number of challenges which make these studies comparably more difficult. Unconventional reservoir geochemistry programs encounter a number of stumbling blocks; in addition to the need to develop methodologies for ‘high-thermal’ maturity oils there is also the question of the core extract material itself. ‘Production Allocation’ studies have traditionally been applied to end-member production oils, in unconventional systems however, the assumption of self-sourced plays with limited migration has shifted the focus to trying to tie the produced fluid directly back to extracted core fluids. This leads to the question as to whether these extracted hydrocarbon fluids are in fact, geochemically, a true representation of ‘end member’ produced fluids. It is well reported that core fluid extraction techniques, whether via solvent, supercritical CO2 or thermal extraction processes, do not mimic geologic processes of produced fluid expulsion and migration. These processes are infinitely quicker and more aggressive than geologic processes and the end result is a fluid which while theoretically close to the associated fluid, will in almost all cases contain components not produced via natural processes. In most core-to-oil reservoir geochemistry correlation studies this is not an issue as quantification is not essential, and most characterization is based upon similarity correlation statistics and some core-to-oil geochemical offset is anticipated. This should also apply to ‘unconventional’ reservoir geochemistry assessments, with the assumption that the capacity to ‘allocate’ production directly back to production zones is going to contain potentially significant error and while useful qualitatively, may be misleading where a defined quantification is assigned. In this presentation we will outline a recent case study from the Delaware Basin in which fluids from a number of target zones were analyzed and characterized (core-to-oil) with samples collected through time to monitor any potential fluid changes indicative of frack induced ‘co-mingling’ processes.
Dr. Barrie graduated from the University of Glasgow, Scotland in 2005 with a 1st class honours degree in Geology, following up with a PhD in Geochemistry and Geology from
the University of Liverpool, England in 2008. Since completing his PhD. Dr. Barrie specialized in mineralogy, advanced microscopy techniques and stable isotopes during his PhD and through teaching and research positions at the University of St. Andrews and the Scottish Universities Environmental Research Center during his postdoctoral tenure. 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 heavily involved with 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 around 30 papers on a range of different sample types and study areas, from environmental and paleoclimate projects through metallic ore resources and petroleum source characterization.
Luncheon sponsored by: