Improved production from biodegraded heavy oil reservoirs
Submitting Institution
Newcastle UniversityUnit of Assessment
Earth Systems and Environmental SciencesSummary Impact Type
TechnologicalResearch Subject Area(s)
Earth Sciences: Geochemistry, Geophysics
Engineering: Resources Engineering and Extractive Metallurgy
Summary of the impact
Newcastle University research on biodegraded petroleum systems has had a
number of broad reaching impacts on the oil industry (ExxonMobil, Statoil,
Woodside, and Shell), related companies (Permedia) and regulators (Alberta
Energy Regulator). A new approach to oil viscosity determination was
developed, which directs well-placement in biodegraded oilfields to lower
viscosity areas, resulting in improved production of heavy oil. Software
tools developed to model oil composition have been incorporated into
proprietary in-house, oil company reservoir simulations. A spin-out
company was founded, Gushor Inc., which provides services to the heavy oil
sector and was recently acquired by Schlumberger. Collectively the
research from Newcastle University has saved oil companies hundreds of
millions of pounds by avoiding poorly producing viscous zones in
biodegraded reservoirs.
Underpinning research
The majority of the world's petroleum deposits comprise heavy oil, which
is difficult and costly to produce and refine and is therefore generally a
less valuable resource than light oil. Heavy oil is formed by
biodegradation of crude oil in situ in petroleum reservoirs over
geological timescales but the factors that lead to in-reservoir
biodegradation were poorly understood prior to this Newcastle University
led research. Our research was aimed at understanding the controls on the
occurrence of biodegraded crude oil, initially in the context of
exploration to avoid targeting biodegraded reservoirs, but subsequently to
understand the effects of biodegradation on petroleum fluid properties and
production strategies.
The research by Newcastle University overturned decades of conventional
wisdom in the oil industry which suggested that in-reservoir
biodegradation was driven by oxygen delivered in meteoric waters, when it
is actually an anaerobic process driven by water-hydrocarbon reactions at
an oil-water contact (OWC) zone [P1-P3]. The key
anaerobic process driving in-reservoir oil biodegradation is, in many
cases, methanogenic crude oil degradation and our research showed that
patterns of methanogenic oil degradation in laboratory incubations are
similar to oils from degraded oil fields that have developed over
geological timescales [P3]. Biodegradation of oil at the OWC at a
rate greater than diffusion from the oil column leads to gradients in the
oil composition and its related fluid properties (e.g. oil viscosity) in
biodegraded petroleum reservoirs [P1, P4]. Furthermore, oil
compositional gradients and viscosity are dictated by the interplay
between reservoir filling and biodegradation over geological timescales [P4].
Understanding the detailed chemical changes in oil composition during
degradation has allowed the development of geochemical means of assessing
oil viscosity enabling reliable viscosity measurements in heavy oilfields,
obviating the need for expensive coring and facilitating the avoidance of
poorly producing viscous zones [P4, P6].
We identified reservoir temperature history as a primary control on
degradation flux, showing that in-reservoir crude oil biodegradation is
prevented if a reservoir has been exposed to temperatures in the region of
80 to 90ºC. This concept that we formulated, is now known as
Palaeopasteurization [P5]. Reservoir geometry, oil water contact
area, oil volume and oil mixing are other important factors affecting oil
biodegradation in reservoirs, and the resulting large fluid property
gradients produced have a major impact on oil recovery processes [P6].
Knowledge of these compositional gradients can be used to target regions
of biodegraded oil fields where the flow properties and hence production
of the oil are most favourable. The same principles also allowed barriers
in reservoirs to be identified permitting the source of production for
individual wells to be determined.
The underpinning research came from a project funded in 3 phases by an
oil company consortium (Bacchus; http://www.ucalgary.ca/prg/bacchus).
Phase I and II were based in Newcastle and Phase III was a joint
enterprise between Newcastle and the University of Calgary (UoC) when one
of the PIs (Larter; Professor of Geology - 1989-present, 2006 joint
appointment with UoC) took up a joint appointment. The research has
generated 54 publications (including 4 nature papers) which collectively
have been cited 1396 times. Other Newcastle researchers include Head
(lecturer, 1992-2000, Reader, 2000-2005, Professor of Environmental
Microbiology, 2005- present), Jones (Analytical Manager,
1989-2007, Lecturer, 2007-2011, Senior Lecturer 2011- present) and Gray
(RCUK Fellow, 2007-2009 , Reader, 2009-present). Eleven
Postdoctoral researchers and 6 PhD students also researched this area over
the lifetime of the Bacchus project.
References to the research
Literature citation data from Scopus
24 September 2013.
[P1] *Head, I.M., Jones, D.M., Larter, S.R. (2003).
Biological activity in the deep subsurface and the origin of heavy oil. Nature
426, 344-352. (269 citations) doi:10.1038/nature02134
[P2] Aitken, C.M., Jones, D.M., Larter, S.R. (2004). Anaerobic
hydrocarbon biodegradation in deep subsurface oil reservoirs. Nature
431, 291-294. (128 citations) doi:10.1038/nature02922
[P3] *Jones, D. M., Head I. M., Gray, N.D., Adams, J.J. ,
Rowan, A.K., Aitken, C.M., Bennett, B., Huang, H., Brown, A., Bowler,
B.F.J., Oldenburg, T. Erdmann, M., Larter, S.R. (2008). Crude-oil
biodegradation via methanogenesis in subsurface petroleum reservoirs. Nature
451, 176-180. (140 citations; Geochemical Society Best Paper Award,
2009) doi:10.1038/nature06484
[P4] *Larter, S., Wilhelms, A., Head, I., Koopmans, M.,
Aplin, A., Di Primio, R., Zwach, Z., Erdmann, M., Telnaes, N. (2003). The
controls on the composition of biodegraded oils in the deep subsurface -
part 1: biodegradation rates in petroleum reservoirs. Organic
Geochemistry 34, 601-613. (109 citations) doi:10.1016/S0146-6380(02)00240-1
[P5] Wilhelms, A., Larter, S.R., Head, I., Farrimond, P.,
Di-Primio, R., Zwach, C. (2001). Biodegradation of oil in uplifted basins
prevented by deep-burial sterilization. Nature 411, 1034-1037 (112
citations) doi:10.1038/35082535
[P6] Larter, S., Adams, J., Gates, I.D., Bennett, B., Huang, H.
(2008). The origin, prediction and impact of oil viscosity heterogeneity
on the production characteristics of tar sand and heavy oil reservoirs.
Journal of Canadian Petroleum Technology, 47 (1), pp. 52-61. (42
citations) doi:10.2118/08-01-52
Grants:
S.R. Larter, I.M. Head. Petroleum Biodegradation: From exploration
towards production (Bacchus projects I, II and III). Period of grants:
01/03/00 - 31/05/04, 01/06/04 - 31/05/07, 02/07/08 - 30/09/11. Value of
grants: £600K, £780K, £578K. Sponsors: Exxon, Norsk Hydro, Petrobras,
Shell, Total-Fina- Elf, Phillips Petroleum, Chevron-Texaco, Japan National
Oil Corporation, BP, Conoco, Statoil, Armco, ENI S.P.A, Woodside,
Anadarko.
Details of the impact
Newcastle research on methanogenic oil biodegradation has had widespread
impacts, not only in academia but on the oil industry (e.g. Statoil,
Woodside, Shell [E1-E4]), related companies (Permedia, [E5])
and oil industry regulators (Alberta Energy Regulator, [E8]). The
research principles and concepts have "...fundamentally revised
understanding of the subsurface process of the biodegradation of
petroleum, which once and for all finished off old obsolete and wrong
process models" (Leader of Petroleum Systems Analysis in Exploration
Research, Statoil [E2]), and "delivered a step-change in our
understanding of biodegradation in hydrocarbon reservoirs" (Principal
Technical Expert for Production Geochemistry, Shell [E4]).
Importantly, take up of the research by industry has been rapid "In
more than twenty years of working in petroleum industry in Europe and
Canada I have never seen industry grasping, and so rapidly applying,
concepts developed by academia as it is case with findings from research
projects led by Drs. Larter and Head" [E1].
The impacts of our research on in-reservoir biodegradation and heavy oil
have been numerous:
- Improved production strategies for heavy oil reservoirs
- New methods for fluid property (viscosity) determination
- A biodegradation module for basin modelling software
- A successful spin out company, Gushor Inc., providing services to the
heavy oil sector
- Provision of concepts used by the regulatory authority for oil sands
development in Alberta
- Impact on popular culture
1. Improved production strategies for heavy oil reservoirs
The identification and explanation of biodegradation-induced oil viscosity
gradients in heavy oilfields has impacted substantially on production
technology. "Vertical compositional gradients of biodegradation
susceptible compounds, another product of biodegradation identified by
the Newcastle/Calgary researchers, have also very rapidly been utilized
by industry for predicting behaviour (rate) of steam growth in thermal
recovery processes" [E1]. Evaluation of viscosity gradients
in heavy oil reservoirs now forms an important part of production process
design in the oil industry with several major oil companies (e.g. Statoil,
Woodside, Shell) with a global footprint incorporating these insights into
their heavy oil businesses [E1-E4]. One project sponsor
specifically highlights how the science developed in the Bacchus project
has had a direct influence on the value of a specific field, "understanding
of the reasons for fluid property variability influenced the decision to
sell the field to another company and also added significant value
(probably in the $10's of millions) to the asset" [E3]. Well
placement to avoid highly viscous oil in poorly producing zones is
informed by knowledge of oil property gradients. It allows detection of
barriers in reservoirs and allocation of the source of production in
complex compartmentalised reservoirs [E1- E3, and E8].
These are now important components of cold and thermal heavy oil recovery
in many parts of the world (e.g. Canada, Oman, Cameroon, Mauritania; E1-E3,
E8). Improved recovery efficiencies with existing heavy oil recovery
processes have resulted from avoiding difficult to recover hydrocarbons
and well placements that could not have worked, improving cost-benefit
ratios and project net present value (NPV) — "the improved picture of
the reservoir fluid state saved the drilling of at least one well at the
cost of ~ $US 50 Million" [E3] and "Considering the number
of projects and tens of billions of dollars of investment in oil sands,
the impact of their new findings can be estimated to be measured in
hundreds of million and perhaps even billions of dollars in the long
term" [E1]. Moreover principles developed from our research
are "routinely used as (i) a screening criterion for caprock integrity
for thermal recovery processes (i.e. presence of gas indicates good
caprock under reservoir conditions) (ii) a tool for evaluating the
geometry and size of these zones and their volumetrics. This is a
critical development risk (water and gas are `thieves' for injected
steam in reservoir and significantly impact the economics of thermal
operations" [E1] and "Numerous projects that have suffered
in the near past would have been a success stories if these principles
had been applied!" [E1].
2. New methods for fluid property (viscosity) determination
Design of optimum production processes requires high quality data on oil
heterogeneity across a reservoir. Understanding the detailed chemical
changes in oil composition during degradation has allowed the development
of geochemical methods for assessing oil viscosity, enabling reliable
viscosity logging from drill cuttings in heavy oilfields "The
temperature-viscosity relationships elucidated in the Bacchus project
helped us predict that traps flanking the anticlinal structures and
hence at slightly higher temperature could contain producible oil" [E3].
This technology is now routinely deployed around the world [E1-E3],
and is being used to reduce costs by providing a low cost alternative to
expensive well testing procedures that rely on obtaining cored reservoir
material that is costly and technically challenging.
3. A biodegradation module for basin modelling software
The fundamental principles developed from our research and specific models
developed have been incorporated into practical software tools developed
in-house by oil company sponsors [E2- E4], for example, "A
predictive framework resulted from the synthesis of data from laboratory
simulations and field studies, and this provides a basis for our
in-house development of improved basin modeling tools" [E4].
Permedia, a company that develops and markets basin modelling software [E5]
worked closely with Bacchus researchers to couple Permedia's high
resolution modelling software with the science base from our oil
biodegradation research. The product is a 3D fluid property prediction
tool that integrates the dynamics of active oil charging with biological
degradation of oil in reservoirs across individual accumulations or for
whole basins. This substantial technical challenge has been met and a tool
("BaccPath") within Permedia's MPath software platform can effectively
predict oil density and viscosity for accumulations through time and
space. An interrogation tool ("Gnawd") developed within our research
spin-out company, Gushor Inc. [E6], models individual reservoir
segments and estimates vertical compositional gradients related to
biodegradation [E6]. Permedia has recently been acquired by
Halliburton and BaccPath has been incorporated into Halliburton's
proprietary software [E5].
4. A successful spin out company providing services to the heavy oil
sector
In 2006, the research led to the formation of a successful spin out
company, Gushor Inc., [E6] which provides services to the heavy oil
industry. Gushor develops reservoir characterisation technologies for
heavy oil reservoirs and specialises in applying understanding of
in-reservoir petroleum biodegradation and its impact on petroleum fluid
properties to design and monitor heavy oil production systems. Gushor
quickly dominated the Canadian heavy oil fluid property characterisation
market and won both technical and commercial accolades including an
Alberta government ASTech award for commercial success in 2009 [E6].
One of the services Gushor provides, ProxViscTM, provides high
resolution oil viscosity data based on geochemical measurements conducted
on drill cuttings and a range of geochemical analysis services for the
heavy oil sector. It also provides the biodegradation modelling software,
Gnawd, and bespoke viscosity reduction technology (BRUTUSTM).
In 2012-2013 Gushor Inc. employed 19 staff and had a turnover of C$3.4
million (£2.08 million). It has provided services to the heavy oil
operations of many major oil companies in China, the North Sea, Columbia,
Brazil, Oman, the Gulf of Mexico, California and Canada [E6]. This
not only underlines the success of Gushor Inc. itself, but provides
evidence of the global application of knowledge and technology that has
been developed as part of our research on biodegraded petroleum reservoirs
and heavy oil. In June 2013, Gushor Inc. was sold to the world's leading
oilfield services provider, Schlumberger, for an undisclosed sum [E7].
5. Provision of concepts used by the regulatory authority for oil
sands development in Alberta
In addition to the industry impacts detailed above Newcastle research on
heavy oil has meant that we have advised regulators such as the Alberta
Energy Regulator (AER) on best practice in energy production from heavy
oil and bitumen reservoirs [E8]. The AER have used our research to
"teach Applications staff the basic principles of oil-sands geology and
technology" and specifically contribute to "understanding bitumen
viscosity variations, and determining recovery factors of bitumen and
heavy oil in oil sands reservoirs to give realistic estimates of
reserves numbers that go into the Province of Alberta budgets" [E8].
6. Impact on popular culture
Our research has provided the basis for a science fiction novel,
"Petroplague" by Amy Rogers [E9] with our research (Jones, et al.
Nature 451, 176-180; Section 3, Reference 3, above) one of the sources
cited in the technical annex (p. 322).
Sources to corroborate the impact
E1. Testimonial: Research Geologist in Heavy Oil Technology
Centre, Statoil Canada Ltd.
E2. Testimonial: Leader of Petroleum Systems Analysis in
Exploration Research, Statoil ASA.
E3. Testimonial: Petroleum Systems Advisor in Sub-Surface
Technology, Shell/Woodside Energy
E4. Testimonial: Principal Technical Expert for Production
Geochemistry, Shell International.
E5. Webpages of the Permedia Research Group (owned by Halliburton
since 2010) describing the incorporation of the Bacchus project
biodegradation module into Permedia MPath basin modelling software. (http://www.permedia.ca/news_july04.html;
http://www.permedia.ca/news_jun09.html)
E6. Webpages that show the existence of Gushor Inc. and that the
spin-out company won the ASTECH Award for outstanding commercial
achievement in Alberta science and technology in 2009. (http://gushor.com/20091111/gushor_wins_2009_astech_award/search;
http://www.youtube.com/watch?v=YkScl9oDtho)
E7. Press releases from the Wall Street Journal, Calgary Herald
and Schlumberger media relations showing that Gushor was sold to
Schlumberger in June 2013. (http://tinyurl.com/q8y28l2;
http://tinyurl.com/ns5fa7c)
E8. Testimonial: Chief Geologist, Alberta Energy Regulator.
E9. Webpage showing the existence of "Petroplague". http://www.sciencethrillers.com/petroplague/;
http://www.amazon.com/Petroplague-Amy-Rogers/dp/1467038261