Oil and Gas
Oil and Gas | Unconventional Resources
Geoscience and Engineering Evaluation of Unconventional Source Rock Reservoirs: The Eagle Ford at Lozier Canyon (Texas, USA)
World-class, completion-scale exposures of the Eagle Ford in Lozier Canyon provide an opportunity to visualize the vertical and lateral variability that occurs along a wellbore in a source rock reservoir and to discuss the geologic and engineering challenges associated with unconventional source rock plays. A unique aspect is the integration of 21st century data similar to the information collected from boreholes and cores in the subsurface. Learnings apply to other resource plays, such as the Woodford, Utica, Marcellus, Haynesville, Duvernay, and Vaca Muerta.
Schedule
Duration and Training Method
This five-day field course starts and ends in Austin, Texas. The first two days will be based in Del Rio, Texas, and the last two in Austin. Fieldwork (60% of time) is supported by lectures and team exercises (20% of time) and core viewing (20% of time). The course is structured so that the week is an ongoing group discussion on unconventional source rock reservoirs. Participants are encouraged to share their own experiences with source rock plays and to bring examples and presentations for discussion.
Course Overview
Learning Outcomes
Participants will learn to:
- Value the power of visualizing subsurface stratigraphy in outcrops hundreds of feet high and thousands of feet in lateral extent.
- Characterize vertical and lateral variations in TOC, maturity, composition and organofacies, as well as thickness variations, of the primary reservoir zones across an unconventional source rock play fairway.
- Evaluate bed-scale variability in mechanical stratigraphy.
- Assess inherited physiography and sequence stratigraphy to explain thickness variations of the primary reservoir zone across a play fairway.
- Gauge the difference in risk factors between unconventional source rock and tight rock plays.
- Integrate outcrop, core, well log, geochemical, and engineering data in an unconventional source rock play.
- Predict the vertical and lateral variability, thickness variations, and sweet spots across the play fairway of an unconventional source rock reservoir.
- Estimate stimulated rock volumes and effective fracture heights in source rock plays, as well as how variations in completion techniques affect production outcomes.
- Investigate the value of bringing outcrops into the 21st Century by collecting petrophysical, geochemical, chemostratigraphic, and biostratigraphic data similar to that collected in the subsurface.
- Value the importance of porting the subsurface stratigraphy to the outcrops, and advoiding local provincial nomenclature.
Course Content
World-class exposures of a source rock and unconventional source rock reservoir are examined in spectacular outcrops of the Eagle Ford Group in Lozier Canyon, an area that few scientists have had to opportunity to visit over the past 50 years. These completion-scale exposures, hundreds of feet high and thousands of feet in lateral extent, provide a unique opportunity to visualize in the minds-eye the vertical and lateral variability that occurs along a well bore within the subsurface in source rock reservoir. The primary canyon exposures are coupled with hikes through side canyons which afford the opportunity to walk bed-by-bed through an unconventional source rock reservoir and six million years in the earth’s history. Highway exposures provide windows to study the underlying Georgetown, Del Rio, and Buda; sample the Eagle Ford; and examine the overlying Austin Group.
The Austin area provides stops to discuss regional thickness variations within source rock plays, conduct exercises, as well as an opportunity to look at unconventional reservoirs in core at the Bureau of Economic Geology.
A unique aspect of all the outcrops that will be visited during the seminar is the integration of 21st century petrophysical, geochemical, chemostratigraphic, biostratigraphic, chronostratigrapic, and sequence stratigraphic data that was collected from the outcrops. These data are similar to the information collected from boreholes and cores in the subsurface and, when coupled with the uniqueness of the Lozier Canyon outcrops, provide unique portals into the Eagle Ford in the subsurface.
Unconventional reservoirs are those reservoirs which have permeability to viscosity ratios that require the technology to alter either the permeability of the rock or the viscosity of the fluid to result in commercial rates of flow. The fracking of horizontal wells has transformed low permeability tight rock and source rock reservoir systems. In Tight Rock plays, the reservoir is not a source rock. Oil and gas migrate into reservoirs typically consisting of coarse silt- to fine sand-sized clastic and carbonate grains. The risk elements are similar to those in conventional reservoirs: reservoir, source, seal, trap, reservoir deliverability, and charge access. In Source Rock plays, the reservoir is also a source rock and typically consists of organic-rich siliceous or calcareous mudstones. The risk elements are very different to those of conventional and tight rock plays, and require focus on TOC, maturity, and reservoir composition, thickness, and pressures.
The focus of this seminar is on unconventional source rock plays, in particular the geologic and engineering learnings from the Eagle Ford Group in the subsurface of South Texas, as well as the outcrops of West Texas. However, the learnings from examination of the Eagle Ford play are applicable to other unconventional source rock plays such as the Woodford, Utica, Marcellus, Haynesville, Duvernay, and Vaca Muerta.
Course Itinerary
Day 1
- Arrive in Austin International Airport by noon, bus drive to Del Rio
- Class: Introductory lecture, safety brief and what to expect; dinner
- Overnight: Del Rio
Day 2
- Field: General west Texas stratigraphy and Eagle Ford introduction
- Overnight: Del Rio
Day 3
- Field: Day-long walk through an unconventional source rock reservoir
- Overnight: Austin
Day 4
- Field, AM: Bouldin Creek outcrops
- Class, PM: BEG Core Repository
- Overnight: Austin
Day 5
- Class, AM: Lecture / exercises / summary / lunch
- Adjourn 1pm, bus drive to airport
Who Should Attend and Prerequisites
The course integrates geoscience and engineering topics and is designed to appeal to geologists, geophysicists, reservoir engineers, completion engineers and drilling engineers. When geoscientists and engineers working on the same asset have attended in the past, they have remarked that the course is a powerful tool to help them develop an integrated approach to unconventional source rock reservoirs.
Instructors
Art Donovan
Background
Dr. Art Donovan has over 30 years of experience in the oil and gas industry and spent over15 years at both ExxonMobil and BP. At ExxonMobil, he conducted and managed sequence and seismic stratigraphic studies from basins around the world, as well as helped to develop and teach numerous courses. At BP, Dr. Donavan served as the sed/strat discipline lead, a member of the Global Exploration Assurance Team, Senior Geoscience Advisor for BP Global Unconventional Efforts, as well as helped rebuild their R&D and internal training efforts globally. After retiring from BP in 2016, he joined the Department of Geology and Geophysics at TAMU as a full-time faculty member in 2017, after serving as an adjunct faculty Member since 2008.
His primary research focus is applying Sequence stratigraphic concepts to help to explain and predict the distributions, thickness variations, and sweet spots of unconventional Source Rock and Tight Rock Reservoirs from the basin- to field-scale. His PhD research at the Colorado School of Mines in the early 1980’s was one of the pioneering efforts to apply sequence stratigraphic concepts to outcrops and the shallow subsurface. Over the past three decades, Art has published numerous articles on the subject, as well as taught sequence stratigraphic courses, and field seminars, for Exxon, BP, GSA, AAPG, SEPM, and The Geological Society.
Affiliations and Accreditation
PhD Colorado School of Mines - Geology
BSc University of Rochester - Geology and Biology
Courses Taught
N438: Geoscience and Engineering Evaluation of Unconventional Source Rock Reservoirs: The Eagle Ford at Lozier Canyon (Texas, USA)
Noel McInnis
Background
Noel McInnis is a Reservoir Engineer who retired in 2016 after 34 years with BP and heritage company Amoco Production Company. He spent the majority of his career working domestic (USA) fields ranging from Permian Basin waterfloods, Wyoming Overthrust sour gas, Anadarko Basin deep gas, Greater Green River Basin tight gas, as well as GOM Shelf exploitation.
Noel spent the last five years as part of BP’s Western Hemisphere Unconventional Exploration Group. His primary focus was shale resource assessment in the Lower 48 (USA) but also included select reservoirs in Canada, Mexico and Argentina. As part of these evaluations he had the opportunity to evaluate well performance across most of the major US unconventional plays, working closely with team geologists, geophysicists and petroleum systems analysts. His interests include the reservoir engineering aspects of completions in these complex unconventional systems
Affiliations and Accreditation
BS, Texas A&M University, 1982
Registered Professional Engineer (Texas)
Courses Taught
N438: Geoscience and Engineering Evaluation of Unconventional Source Rock Reservoirs: The Eagle Ford at Lozier Canyon (Texas, USA)