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Inventory of Class II Underground Injection Control Volumes in the Midcontinent

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Water and other fluids have been injected into the subsurface for decades in enhanced oil recovery (EOR) operations and for saltwater disposal (SWD). In recent years, hydraulic fracturing and horizontal wells have allowed development of unconventional oil and gas res¬ervoirs or to redevelop conventional resources. Intense leasing, drilling, and production from the Mississippian zone of southern Kansas and northern Oklahoma are prime examples of this. Because it is economic to produce at low oil-cuts such as in the Mississippian, there is a disproportionate increase in the co-production of water. After separating water from oil and gas at the wellhead, producers are left with co-produced water having ~150,000 ppm median concentrations of total dissolved solids which is typically disposed of in SWD wells. Research has cited an increasing number of seismic events in the midcontinent, some of which are potentially induced by fluid injec¬tion. Unfortunately, limited data are published for volumes and pressures of fluids injected or distribution of those fluids into subsurface zones. The objectives of this research were to compile Class II underground injection control (UIC) data for the year 2011 and inventory injection data by geologic zone in Kansas and Oklahoma. EOR injected (EORI) fluid volumes totaled 265.5 million barrels (MMbbl) in Kansas and 1093 MMbbl in Oklahoma with the Desmoinesian and Atokan-Morrowan zones receiving the highest EORI fluid volumes. SWD volumes totaled 754.0 MMbbl in Kansas and 891.9 MMbbl in Oklahoma with the Arbuckle and Devonian to Middle Ordovician zones receiving the highest SWD volumes. The Arbuckle Group is underpressured throughout most of the midcontinent and has an unwavering capacity to accept fluids without any observed increases in pressure. Future studies of relationships between fluid injection and seismicity must carefully compare extraction/injection histories, characterize hydrogeologic parameters, identify critically stressed faults, and explain mechanisms by which pore pressure diffuses or increases stress along a fault plane.
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THE JOURNAL OF THE OKLAHOMA CITY GEOLOGICAL SOCIETY
VOLUME 65 NUMBER 2
120 North Robinson, Suite 900 Center
Oklahoma City, OK 73102
~ MARCH | APRIL 2014 ~
Structural Analysis of the Boktukola Syncline,
Central Ouachita Mountains, Oklahoma;
Inventory of Class II Underground Injection Control
Volumes in the Mid-Continent;
And Much More.
Page 98 | March ~ April 2014
By Kyle E. Murray, Oklahoma Geological Survay | kyle.murray@ou.edu; Austin A. Holland, Oklahoma
Geological Survey | austin.holland@ou.edu
Resource Management
Inventory of Class II Underground Injection
Control Volumes in the Midcontinent
ABSTRACT
Water and other uids have been injected into the subsurface for decades in enhanced oil recovery (EOR) operations and for saltwater
disposal (SWD). In recent years, hydraulic fracturing and horizontal wells have allowed development of unconventional oil and gas res-
ervoirs or to redevelop conventional resources. Intense leasing, drilling, and production from the Mississippian zone of southern Kansas
and northern Oklahoma are prime examples of this. Because it is economic to produce at low oil-cuts such as in the Mississippian, there
is a disproportionate increase in the co-production of water. After separating water from oil and gas at the wellhead, producers are left
with co-produced water having ~150,000 ppm median concentrations of total dissolved solids which is typically disposed of in SWD
wells.
Research has cited an increasing number of seismic events in the midcontinent, some of which are potentially induced by uid injec-
tion. Unfortunately, limited data are published for volumes and pressures of uids injected or distribution of those uids into subsurface
zones. The objectives of this research were to compile Class II underground injection control (UIC) data for the year 2011 and inventory
injection data by geologic zone in Kansas and Oklahoma. EOR injected (EORI) uid volumes totaled 265.5 million barrels (MMbbl) in
Kansas and 1093 MMbbl in Oklahoma with the Desmoinesian and Atokan-Morrowan zones receiving the highest EORI uid volumes.
SWD volumes totaled 754.0 MMbbl in Kansas and 891.9 MMbbl in Oklahoma with the Arbuckle and Devonian to Middle Ordovician
zones receiving the highest SWD volumes. The Arbuckle Group is underpressured throughout most of the midcontinent and has an
unwavering capacity to accept uids without any observed increases in pressure. Future studies of relationships between uid injection
and seismicity must carefully compare extraction/injection histories, characterize hydrogeologic parameters, identify critically stressed
faults, and explain mechanisms by which pore pressure diffuses or increases stress along a fault plane.
March ~ April 2014 | Page 99
INTRODUCTION
Fluid Production in the U.S. Midconti-
nent (Kansas and Oklahoma)
Petroleum production began in the U.S.
midcontinent before 1900. Oil and gas
have both been continuously produced
in Kansas and Oklahoma since 1906. Oil
production in Kansas during 1906 was
approximately 3.63 million barrels of oil
(MMBO) and peaked at ~124 MMBO in
1956 (Adkins-Heljeson, 2013) as shown
in Figure 1. Oil production in Oklahoma
during 1906 was approximately 18.1
MMBO and peaked at ~278 MMBO in
1927 (OCC, 2012) as shown in Figure 2.
Gas production in Kansas during 1906
was approximately 12.2 million barrels
of oil equivalent (MMBOE) and peaked
at ~160 MMBOE in 1970 (Adkins-Helje-
son, 2013; EIA, 2013b). Gas production
in Oklahoma during 1906 was approxi-
mately 0.62 MMBOE and peaked at ~399
MMBOE in 1990 (EIA, 2013b; OCC,
2012).
Since the year 2000 there has been an
increase in the proportion of horizontal
wells and hydraulic fracturing to stimu-
late producing formations in Oklahoma
(Murray, 2013). Horizontal wells and hy-
draulic fracturing have increased produc-
tion from unconventional shale plays and
contributed to a resurgence of production
from conventional sandstone and carbon-
ate reservoirs in the midcontinent. Crude-
oil production was approximately 41.5
MMBO in Kansas and ~76.7 MMBO in
Oklahoma during 2011, ranking as the
9th and 5th highest producing U.S. states,
respectively (EIA, 2013a). Gross natural-
gas production was approximately 43.7
MMBOE in Kansas and ~89.3 MMBOE
in Oklahoma during 2011, ranking as the
13th and 5th highest producing U.S. states,
respectively (EIA, 2013b).
Dewatering projects, such as in the Hunton
Lime, are prevalent throughout the mid-
continent. Other plays, such as the Missis-
sippian of southern Kansas and northern
Oklahoma, also produce large volumes of
water per unit of oil or gas. By multiply-
ing water:oil ratio (3.7) by oil production
and water:gas ratio (2.1) by oil-equivalent
gas production, Murray (2013) estimated
Oklahoma’s statewide produced-water
volumes to range from 811 to 925 MMbbl
between 2000 and 2011. Historic (i.e., pri-
or to 2000) produced-water volumes are
difcult to estimate, but may have been
similar to present-day volumes assuming
that lower water:oil and water:gas ratios
from conventional production were offset
by higher petroleum-production rates that
peaked between ~1960 and ~1980 (Figure
1) and between ~1965 and ~1995 (Figure
2) in Kansas and Oklahoma, respectively.
Underground Injection Control (UIC)
Well Designations
The underground injection control (UIC)
program was implemented by the U.S.
Environmental Protection Agency (EPA)
in the 1980s to manage and regulate uid
injections into the subsurface. Six UIC
well designations (Class I, II, III, IV, V,
and VI) are used to manage injections
from various industries. The EPA main-
tains regulatory authority over subsurface
uid injection but may delegate author-
ity of Class II wells to state agencies.
The Kansas Corporation Commission
and Oklahoma Corporation Commission
are delegated authority over Class II UIC
wells, except in Osage County, Oklahoma
where EPA maintains authority. Current
regulatory controls over Class II UIC
wells were designed to protect potable-
water sources from contamination. Class
II UIC wells fulll two basic purposes
in the oil and gas sector, enhanced oil-
recovery injection (EORI) and salt-water
disposal (SWD). EORI wells are designed
Figure 1. Annual eld producon of crude oil and annual natural gas gross withdrawal in Kansas from 1906 to 2012. Sources: Adkins-Heljeson
(2013) and EIA (2013b)
Page 100 | March ~ April 2014
Inventory of Class II Underground Injection Control Volumes in the Midcontinent, cont.
Resource Management
to inject uids (water and/or CO2) into the
subsurface to mobilize oil and/or gas into
production wells. During EORI, pressure
across the eld is monitored so as not to
exceed virgin pressure conditions. SWD
wells are designed to dispose of brine wa-
ter that was co-produced with oil and gas.
SWD wells ideally function on a vacuum
or require low wellhead-injection pres-
sures.
Potential for Induced Seismicity from
Fluid Injection
Fluid injection, including EORI (Davis
and Pennington, 1989) and SWD (Hor-
ton, 2012; Keranen et al., 2013; Nichol-
son and Wesson, 1990), have been shown
to contribute to seismicity mainly by re-
ducing normal stress so that movement
occurs along a pre-existing fault (Healy
et al., 1968; NRC, 2012; Raleigh et al.,
1976). Some of the largest magnitude
earthquakes associated with SWD injec-
tions were centered in the midcontinent
states of Arkansas, Oklahoma, and Texas
(Frohlich, 2012; Horton, 2012; Keranen
et al., 2013). Regardless of potential con-
nections, research on the topic of induced
seismicity recognizes the uncertainty and
the difculty in distinguishing between
natural or induced seismic events. One
major limitation of this line of research re-
lates to the unknown quality of UIC data
including x-y location, z elevation, zone
of completion, volume and pressure. Inte-
grated hydrogeologic, structural geologic,
and seismologic studies are required be-
cause mechanisms for uid-injection in-
duced seismicity are related to stresses
and strength of faults, hydraulic properties
of injection zones, and pressure diffusion
(Ellsworth, 2013; Holland, 2013).
Objectives
Absent from the uid-injection induced
seismicity literature are broad-scale per-
spectives on uid-injection volumes and
pressures and accurate reporting of geo-
logic intervals that receive those uids.
The objectives of this research were to
compile and summarize volumes of water
used for EORI and SWD in the midconti-
nent and summarize volumes by geologic
injection zone.
METHODOLOGY
Because data related to UIC programs in
Kansas and Oklahoma were reported to
multiple organizations and uniquely for-
matted, multiple databases were designed
and maintained during the course of this
research. API numbers were used to man-
age data associated with unique well loca-
tions.
Compile UIC Well Locations and Injec-
tion Volumes
Fluid-injection volumes into Class II
UIC wells in 2011 were obtained from
the Kansas Corporation Commission and
the Oklahoma Corporation Commission
(Lord, 2012; Snider, 2013) and used to
create a relational database for each state
(i.e., Kansas UIC and Oklahoma UIC).
Records were managed using API num-
ber when appending data to the respective
Kansas UIC or Oklahoma UIC database.
Well-completion data were obtained from
the Kansas Geological Survey or Okla-
homa Corporation Commission well da-
tabases and interactive web-sites (KGS,
2013; OCC, 2013). Fluid injections in
Osage County, Oklahoma Class II UIC
wells, regulated by EPA, have different
reporting procedures, therefore, were not
included in this study.
Attribute Injection Zones for Wells
Injection zones were represented using
twelve categories: Permian, Virgilian,
Missourian, Desmoinesian, Atokan-Mor-
Figure 2. Annual eld producon of crude oil and annual natural gas gross withdrawal in Oklahoma from 1906 to 2012. Sources: EIA (2013b) and
OCC (2012)
March ~ April 2014 | Page 101
rowan, Mississippian, Woodford, Devo-
nian to Middle Ordovician (Dev to Mid
Ord), Arbuckle, Basement, Multiple-Un-
differentiated, and Other or Unspecied.
‘Producing’ or ‘injection’ formation(s)
were correlated to the appropriate zone
(Figure 3) based on the Stratigraphic
Guide to Oklahoma Oil and Gas Reser-
voirs (Boyd, 2008). When producing or
injection formation was not specied in
the Kansas UIC or Oklahoma UIC data-
bases, the completion reports (e.g., Okla-
homa Corporation Commission’s Form
1002A) or other digitally accessible re-
cords were examined for each API number
in Kansas (http://www.kgs.ku.edu/Magel-
lan/Qualied/index.html) or Oklahoma
(http://www.occpermit.com/WellBrowse/
Home.aspx). The injection formation(s)
for the most recent completion of each
API number was determined, when pos-
sible, and added as an attribute. When re-
cords indicated that the injection interval
consisted of multiple groups or forma-
tions (e.g., Bartlesville and Dutcher) from
more than one zone, then the well was
attributed as ‘Multiple-Undifferentiated.’
When records indicated that a formation
(e.g., Cretaceous Niobrara) other than the
ten designated zones (Figure 3) was used
for injection or the target formation was
not discernible, the well was attributed as
‘Other or Unspecied.’
Summarize Volumes by Injection Zones
Class II underground injection control
wells were selected (i.e., queried) within
the Kansas UIC and Oklahoma UIC da-
tabases, grouped by injection zone and
injection type (e.g., EORI or SWD), and
injection volumes were summed. From
these queries, total water-injection vol-
umes were estimated for each zone in
Kansas and Oklahoma during 2011.
RESULTS AND DISCUSSION
The Kansas UIC database contained 9559
UIC wells of which 6118 wells had report-
ed EORI water volumes and 3441 wells
had SWD volumes in 2011. The Okla-
Figure 3. Correlaon chart of groups, sub-groups or formaons comprising injecon zones.
Modied from Stragraphic Guide to Oklahoma Oil and Gas Reservoirs (Boyd, 2008).
Page 102 | March ~ April 2014
Inventory of Class II Underground Injection Control Volumes in the Midcontinent, cont.
Resource Management
Figure 4. Fluid volumes injected, by zone, into UIC wells in Kansas during 2011.
Figure 5. Fluid volumes injected, by zone, into UIC wells in Oklahoma during 2011.
March ~ April 2014 | Page 103
homa UIC database contained 9630 UIC
wells of which 5506 had reported EORI
water volumes and 4124 wells has SWD
volumes in 2011.
Class II UIC Statewide Volumes by
Geologic Injection Zone
Total volume of EORI uid in Kansas
was ~265.5 MMbbl in 2011. A substantial
number of Kansas UIC wells were not at-
tributed with a known injection zone, so
the largest EORI volumes are illustrated
in Figure 4 as going to ‘Other or Unspeci-
ed’ zones. Injection zones in Kansas re-
ceiving the largest volumes of EORI uid
were the Atokan-Morrowan and Missou-
rian. Total volume of EORI uid injection
in Oklahoma was 1093 MMbbl in 2011.
The Desmoinesian (278.3 MMbbl) and
Atokan-Morrowan (259.2 MMbbl) zones
received the largest volumes of EORI
uid in Oklahoma (Figure 5). EORI vol-
umes into the Arbuckle and underlying
PreCambrian Basement zones were mini-
mal, which suggests that EORI has a low
probability of inducing seismic activity.
Total volume of SWD in Kansas was
~754.0 MMbbl in 2011. Because the com-
pletion zones were unknown for a high
percentage of Kansas UIC wells, the larg-
est SWD volumes are illustrated in Figure
4 as going to ‘Multiple-Undifferentiated’
and ‘Other or Unspecied’ zones. The Ar-
buckle and Mississippian zones received
Figure 6. Locaons of EORI wells in the midconnent. Faults from Cole (1976), Nodine-Zeller and Thompson (1977), and Northcu and Campbell
(1995).
Page 104 | March ~ April 2014
Inventory of Class II Underground Injection Control Volumes in the Midcontinent, cont.
Resource Management
the largest amounts of SWD in Kansas.
Total volume of SWD in Oklahoma was
~891.9 MMbbl in 2011 as illustrated in
Figure 5. The Arbuckle (440.1 MMbbl)
and Permian (68.5 MMbbl) zones re-
ceived the largest amounts of SWD uid
in Oklahoma, with substantial amounts
also being injected into Multiple-Undif-
ferentiated (125.5 MMbbl) zones. Be-
cause the Arbuckle directly overlies the
Precambrian basement, SWD wells have
higher probability (than EORI wells) for
inducing seismicity. Those wells that are
completed in the Basement or attributed
as ‘Multiple-Undifferentiated’ with com-
pletion intervals in the Basement should
be further examined (e.g., proximity to
faults) to reduce risk of induced seismic-
ity.
Highest Volume Class II UIC Wells
There were many active EORI wells in
Kansas (6118) and Oklahoma (5506)
during 2011; however, only a small frac-
tion (0.27%) of the EORI wells, shown
in Figure 6, injected substantial volumes
(>150,000 bbl/mon). This injection rate
was notable in the Barnett Shale region
of Johnson County, Texas where 33.3% of
the UIC wells exceeded 150,000 bbl/mon
and seismicity was potentially induced
(Frohlich, 2012).
There were also many active SWD wells
in Kansas (3441) and Oklahoma (4124)
Figure 7. Locaons of SWD wells in the midconnent. Faults from Cole (1976), Nodine-Zeller and Thompson (1977), and Northcu and Campbell
(1995).
March ~ April 2014 | Page 105
REFERENCES CITED
Adkins-Heljeson, D., 2013, unpublished
data, Database of historic oil and
gas production in Kansas: Lawrence,
Kansas, Kansas Geological Survey.
Boyd, D. T., 2008, Stratigraphic guide
to Oklahoma oil and gas reservoirs:
Oklahoma Geological Survey Special
Publication 2008-1.
Cole, V.B., 1976, Conguration of the
top of Precambrian rocks in Kansas:
Kansas Geological Survey, Map M-7,
scale 1:500:000.
Davis, S.D., and W.D. Pennington, 1989,
Induced seismic deformation in the
Cogdell oil eld of west Texas: Bul-
letin of the Seismological Society of
America, v. 79, p. 1477-1495.
EIA, 2013a, Field Production of Crude
Oil in the United States: Washing-
ton, DC, U.S. Department of Energy.
http://www.eia.gov/dnav/pet/hist/
-, 2013b, Natural Gas Gross Withdraw-
als and Production: Washington, DC,
U.S. Department of Energy. http://
www.eia.gov/dnav/pet/pet_crd_crp-
dn_adc_mbbl_a.htm
Ellsworth, W.L., 2013, Injection-induced
earthquakes: Science, v. 341, p. 142-
149.
Frohlich, C., 2012, Two-year survey
comparing earthquake activity and
injection-well locations in the Barnett
Shale, Texas: Proceedings of the Na-
tional Academy of Sciences, v. 109,
no. 35, p. 13,934-13,938.
Healy, J.H., W.W. Rubey, D.T. Griggs,
and C.B. Raleigh, 1968, The Denver
earthquakes: Science, v. 161, p. 1301-
1310.
Holland, A.A., 2013, Earthquakes trig-
gered by hydraulic fracturing in
south-central Oklahoma: Bulletin of
the Seismological Society of Ameri-
ca, v. 103, p. 1784-1792.
Horton, S., 2012, Disposal of hydrofrack-
ing waste uid by injection into sub-
surface aquifers triggers earthquake
wwarm in central Arkansas with
potential for damaging earthquake:
Seismological Research Letters, v.
83, p. 250-260.
Keranen, K.M., H.M. Savage, G.A. Abers,
and E.S. Cochran, 2013, Potentially
induced earthquakes in Oklahoma,
USA: Links between wastewater in-
jection and the 2011 Mw 5.7 earth-
quake sequence: Geology, v. 41, p.
699-702.
KGS, 2013, Oil and Gas Well Database:
Lawrence, Kansas, Kansas Geologi-
cal Survey. http://www.kgs.ku.edu/
Magellan/Qualied/index.html
Lord, C., 2012, Monthly injection vol-
umes for Class II Underground In-
jection Control (UIC) wells in Okla-
homa, 2011: Oklahoma City, Oklaho-
ma, Oil and Gas Division, Oklahoma
Corporation Commission.
Murray, K.E., 2013, State-scale perspec-
tive on water use and production as-
sociated with oil and gas operations,
Oklahoma, U.S.: Environmental Sci-
ence & Technology, v. 47,p. 4918-
4925.
Nicholson, C., and R.L. Wesson, 1990,
Earthquake hazard associated with
deep well injection-A report to the
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during 2011. A small fraction (2.64%) of
the SWD wells in Kansas and Oklahoma
exceeded 150,000 bbl/mon (Figure 7).
Research Priorities for Understanding
Fluid-Injection-Induced Seismicity
Measurement of pre-injection hydrologic
conditions and formation pressure, along
with increased temporal resolution of in-
jection rates and pressures are critical for
understanding the dynamic relationships
between uid injection and seismicity
(Ellsworth, 2013). Thorough evaluation
of the presence or absence of faulting near
uid-injection wells (Frohlich, 2012) is
also a priority for understanding potential
for induced seismicity. Reasonable esti-
mates of eld-scale historic and future u-
id-injection and withdrawal volumes must
be made for all production or injection
zones so that critical pore pressures can
be understood. Integrated hydrogeologic,
structural geologic, and seismologic da-
tasets may then be evaluated to establish
mechanisms by which uid injection in-
creases pore pressure along a fault plane.
These integrated scientic studies would
be useful for the development of adapt-
able regulatory requirements and best-
management practices for uid injection.
ACKNOWLEDGEMENTS
The authors acknowledge colleagues at
the Oklahoma Geological Survey for re-
viewing preliminary versions of this ar-
ticle. Charles Lord of the Oklahoma Cor-
poration Commission and Alan Snider of
the Kansas Corporation Commission are
acknowledged for providing UIC vol-
umes data in the midcontinent. Analyses
presented in this article are based on in-
formation available to the authors, and do
not necessarily represent the views of the
Oklahoma Geological Survey, University
of Oklahoma, their employees, or the State
of Oklahoma. The accuracy of the infor-
mation contained herein is not guaranteed
by the authors, Oklahoma Geological Sur-
vey, or the University of Oklahoma.
Page 106 | March ~ April 2014
Inventory of Class II Underground Injection Control Volumes in the Midcontinent, cont.
Resource Management
Nodine-Zeller, D.E., and T.L. Thompson,
1977, Age and structure of subsurface
beds in Cherokee County, Kansas:
Implications from endthyrid foramin-
ifera and conodonts: Lawrence, KS,
Kansas Geological Survey, 11 p.
Northcutt, R.A., and J.A. Campbell, 1995,
Geologic provinces of Oklahoma:
Oklahoma Geological Survey Open-
File Report 5-95, scale 1:750,000.
NRC, 2012, Induced Seismicity Potential
in Energy Technologies, Washington,
DC, National Academy of Sciences,
225p.
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ral Gas Activity Within the State of
Oklahoma: Technical Services De-
partment, Oil and Gas Conservation
Commission. http://digitalprairie.
ok.gov/cdm/ref/collection/stgovpub/
id/168874
-, 2013, Well Data System: Oklahoma
City, Oklahoma, Oklahoma Corpora-
tion Commission. http://www.occper-
mit.com/WellBrowse/Home.aspx
Raleigh, C.B., J.H. Healy, and J.D. Brede-
hoeft, 1976, An experiment in earth-
quake control at Rangely, Colorado:
Science, v. 191, p. 1230-1237.
Snider, A., 2013, unpublished data,
Monthly injection volumes for Class
II Underground Injection Control
(UIC) wells in Kansas, 2011 and
2012: Topeka, Kansas, Oil and Gas
Conservation Division, Kansas Cor-
poration Commission.
Biographical Sketch
Kyle E. Murray has worked as a Hydrogeologist for the Oklahoma Geological Survey (OGS) since 2011.
He earned a B.A. in Geography/Environmental Studies from Shippensburg University-Pennsylvania in
1995, an M.S. in Hydrogeology from Wright State University-Ohio in 1997, and a Ph.D. in Geological
Engineering from Colorado School of Mines-Colorado in 2003. Kyle lived in Colorado from 1997 to
2004, during which he worked as an environmental consultant and a GIS Specialist for the USGS. From
2004 to 2011, he was a faculty member in the Departments of Geology and Environmental Science and
Engineering at the University of Texas at San Antonio.
After joining the OGS, Kyle was appointed as an adjunct faculty member in the ConocoPhillips School
of Geology and Geophysics at the University of Oklahoma (OU). Dr. Murray supervises undergraduate and graduate research
projects involving geology, hydrogeology, and petroleum geology of Oklahoma. Kyle’s research emphasis at OGS and OU is
on the interplay between water and energy resources. He has presented this line of research in public venues and conferences
held by GWPC, GSA, AAPG, and NGWA. In 2014, he is partnering with OERB’s committee for Sustaining Oklahoma’s Energy
Resources to present Produced Water workshops in Ardmore, Woodward, Tulsa, and Oklahoma City.
Kyle E. Murray
Biographical Sketch
Austin Holland is a research seismologist with the Oklahoma Geological Survey (OGS). He has been
with the OGS since January of 2010. Since arriving at the OGS Austin has worked on issues of triggered
seismicity. He is currently nishing his Ph.D. at the University of Arizona where his focus was primarily
on measuring deformation of the Earth using high precision GPS and earthquake seismology. He
received his Masters of Science in Geophysics from the University of Texas at El Paso, and his Bachelors
of Science in Geology from the University of Idaho. He worked at the Department of Energy’s Idaho
National Laboratory for 12 years in the seismic monitoring program.
Austin Holland
... Simplified stratigraphic guide to geologic zones targeted in Oklahoma for completion of petroleum producing or saltwater disposal wells, modified from Murray and Holland (2014) and based on Boyd (2008) and Cipriani (1963) Map of saltwater disposal (SWD) wells for all disposal zones symbolized with relative disposal rate (bbl/yr), also showing regional-scale fault locations (Holland 2015), and geologic provinces (Northcutt and Campbell 1995 Map of saltwater disposal (SWD) wells for Arbuckle disposal zone symbolized with relative disposal rate (bbl/yr), also showing regional-scale fault locations (Holland 2015), and geologic provinces (Northcutt and Campbell 1995 Based on data compiled for this report, estimated statewide (excluding Osage County) SWD volumes were 849, 861, 976, 1051, 1326, and 1538 million barrels (MMbbl) for the respective years 2009-2014. Annual SWD volumes increased substantially (i.e., more than 50 MMbbl) in Alfalfa (+282 MMbbl), Grant (+70 MMbbl), Woods (+67 MMbbl), Payne (+63 MMbbl), and Garfield (+50 MMbbl) Counties from 2009-2014, while SWD volumes decreased substantially in only Lincoln County (-56 MMbbl) over that same time period. ...
... Petroleum was produced in Oklahoma before 1900 and has been continuously produced and reported for more than 100 years ( Figure 1). Oil production peaked at about 278 million barrels of oil (MMBO) in 1927 (Murray and Holland 2014) and gas production peaked at about 376 million barrels of oil equivalent (MMBOE) in 1990 (EIA 2015). Less than 100 MMBO per year were produced in Oklahoma after 1992 with an annual low of about 61 MMBO in 2005, but a resurgence in production occurred in recent years because of technological innovation and economic drivers (Murray and Holland 2014). ...
... Oil production peaked at about 278 million barrels of oil (MMBO) in 1927 (Murray and Holland 2014) and gas production peaked at about 376 million barrels of oil equivalent (MMBOE) in 1990 (EIA 2015). Less than 100 MMBO per year were produced in Oklahoma after 1992 with an annual low of about 61 MMBO in 2005, but a resurgence in production occurred in recent years because of technological innovation and economic drivers (Murray and Holland 2014). In 2014, about 128 MMBO were produced in Oklahoma, largely from sandstone and carbonate dominated zones (Murray 2016-in preparation). ...
Technical Report
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This report is an update for an ongoing research effort to compile Oklahoma’s Class II underground injection control (UIC) well data by geologic zone of completion on annual-, state-, and county- scales. Because most previous studies indicate that saltwater disposal (SWD) wells are of greater concern than enhanced oil recovery injection (EORI) wells, only SWD data were compiled, updated, and reported. Thousands of annual fluid injection, well completion, mechanical integrity test, and permit reports, filed by operators with the Oklahoma Corporation Commission (OCC), were the primary sources of data. SWD well data were compiled into a relational database, checked against scanned and electronic OCC records, and then summarized at annual-, state-, and county- scales. Based on data compiled for this report, estimated statewide (excluding Osage County) SWD volumes were 849, 861, 976, 1051, 1326, and 1538 million barrels (MMbbl) for the respective years 2009–2014. Annual SWD volumes increased substantially (i.e., more than 50 MMbbl) in Alfalfa (+282 MMbbl), Grant (+70 MMbbl), Woods (+67 MMbbl), Payne (+63 MMbbl), and Garfield (+50 MMbbl) Counties from 2009–2014, while SWD volumes decreased substantially in only Lincoln County (-56 MMbbl) over that same time period. Increases in SWD volumes likely coincided with the onset of dewatering operations in the Hunton Lime and Mississippian plays, which produce large volumes of water per unit of oil or gas. The Arbuckle basal sedimentary strata were the target for the majority of Class II UIC SWD volumes in Oklahoma. Statewide Arbuckle zone SWD volumes comprised more than 50% of the statewide total with about 434 (51%), 449 (52%), 525 (54%), 566 (54%), 843 (64%), and 1047 (68%) MMbbl for the respective years 2009–2014. Arbuckle zone SWD wells are predominantly located in the Cherokee Platform or Anadarko Shelf geologic provinces where Hunton and Mississippian operations were active. Mean disposal rates for SWD wells completed in the Arbuckle zone substantially increased in 2013 to more than 1 MMbbl/yr and increased again in 2014 to more than 1.2 MMbbl/yr. In future research, the UIC database will be continuously appended and updated with historic (≤ 2008) and new (2015 to present) data at a monthly timescale. Studies will continue to investigate geologic variability and properties of various zones, especially the Arbuckle because it is the primary disposal zone in Oklahoma. SWD data will be integrated with other geologic data to better understand complex relationships between hydrogeology, geomechanics, seismology, market forces, operational changes, and regulatory controls.
... According to the Oklahoma Geological Survey, the earliest recorded earthquake in the state Crude oil and natural gas have been extracted from Oklahoma's underground for more than 100 years [29]. Between 2010 and 2012 Oklahoma was ranked as the 5th highest producing U.S. state [29]. ...
... According to the Oklahoma Geological Survey, the earliest recorded earthquake in the state Crude oil and natural gas have been extracted from Oklahoma's underground for more than 100 years [29]. Between 2010 and 2012 Oklahoma was ranked as the 5th highest producing U.S. state [29]. The high oil and gas production rates caused a rapid increase in construction of underground injection Class II (UIC) wells, widely used to enhance the recovery of oil (EOR Enhanced Oil Recovery wells) and disposing of industrial wastewater (SWD) since the 1930s [30]. ...
... The high oil and gas production rates caused a rapid increase in construction of underground injection Class II (UIC) wells, widely used to enhance the recovery of oil (EOR Enhanced Oil Recovery wells) and disposing of industrial wastewater (SWD) since the 1930s [30]. Figure 3a Crude oil and natural gas have been extracted from Oklahoma's underground for more than 100 years [29]. Between 2010 and 2012 Oklahoma was ranked as the 5th highest producing U.S. state [29]. ...
Article
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In this study we present a spatiotemporal analysis of the recent seismicity and industry-related wastewater injection activity in Oklahoma. A parsimonious predictive tool was developed to estimate the lagged effect of previous month’s injection volumes on subsequent regional seismic activity. Results support the hypothesis that the recent boom in unconventional oil and gas production and either the mitigation policies or the drop in oil prices (or both) are potentially responsible for the upsurge and reduction in the state’s seismic activity between 2006–2015 and 2016–2017, respectively. A cluster analysis reveals a synchronous migration pattern between earthquake occurrences and salt water injection with a predominant northwest direction during 2006 through 2017. A lagged cross-correlation analysis allows extracting a power law between expected number of quakes and weighted average monthly injection volumes with a coefficient of determination of R2 = 0.77. Such a relation could be used to establish “sustainable water injection limits” aiming to minimize seismicity to values comparable with several historically representative averages. Results from these analyses coincide on previously found sustainable limits of 5 to 6 million m3/month but expand to operations that could attain the same number through differential monthly planning. Findings could potentially be used for model intercomparison and regulation policies.
... This model is, however, applicable only if fault systems are critically stressed before injection. The Arbuckle group, where most injection occurred, is naturally underpressured throughout most of the midcontinent (40,41). Thus, during the early stage of injection, the fluid was used to compensate for the pressure deficit, and only when the pressure was high enough to propagate into the basement was it able to trigger seismicity. ...
... However, the inherent assumption associated with the Dieterich (20) model is that the background stress is sufficiently high relative to the shear resistance that the background stressing rate leads to a nonzero seismicity rate. Given that the Arbuckle formation is naturally underpressured (40,41), an amount of fluid is initially needed to compensate for the pressure deficit before the seismicity rate increases. Thus, to solve for the seismicity rate associated with the imparted CSR, we considered a regional critical time t crit (when seismicity rate starts to deviate from its background value): dRðx, tÞ dt = Rðx, tÞ t a _ τðx, tÞ _ τ 0 − Rðx, tÞ , t ≥ t crit dRðx, tÞ dt = Rðx, tÞ t a ð1 − Rðx, tÞÞ, t < t crit , [3] where _ τ 0 is the background stressing rate, A is a constitutive parameter in the rate-and-state friction law, σ is the background effective normal stress, and t a = Aσ _ τ0 is the characteristic relaxation time. ...
Article
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Induced seismicity linked to geothermal resource exploitation, hydraulic fracturing, and wastewater disposal is evolving into a global issue because of the increasing energy demand. Moderate to large induced earthquakes, causing widespread hazards, are often related to fluid injection into deep permeable formations that are hydraulically connected to the underlying crystalline basement. Using injection data combined with a physics-based linear poroelastic model and rate-and-state friction law, we compute the changes in crustal stress and seismicity rate in Oklahoma. This model can be used to assess earthquake potential on specific fault segments. The regional magnitude–time distribution of the observed magnitude (M) 3+ earthquakes during 2008–2017 is reproducible and is the same for the 2 optimal, conjugate fault orientations suggested for Oklahoma. At the regional scale, the timing of predicted seismicity rate, as opposed to its pattern and amplitude, is insensitive to hydrogeological and nucleation parameters in Oklahoma. Poroelastic stress changes alone have a small effect on the seismic hazard. However, their addition to pore-pressure changes can increase the seismicity rate by 6-fold and 2-fold for central and western Oklahoma, respectively. The injection-rate reduction in 2016 mitigates the exceedance probability of M5.0 by 22% in western Oklahoma, while that of central Oklahoma remains unchanged. A hypothetical injection shut-in in April 2017 causes the earthquake probability to approach its background level by ∼2025. We conclude that stress perturbation on prestressed faults due to pore-pressure diffusion, enhanced by poroelastic effects, is the primary driver of the induced earthquakes in Oklahoma.
... The compressibility of water and weight density of water were obtained for values of brine with approximately 150,000 ppm, which is a value typical for saltwater (Murray and Holland, 2014). ...
... relates porosity (η), specific storage (SS), compressibility of water (βw), and density of water (ρw). Values for βw and ρw were obtained for brine with TDS of approximately 150,000 ppm, which is a value typical for brine in Oklahoma reservoirs (Murray and Holland, 2014). ...
Thesis
The Arbuckle Group is an important geologic unit in the state of Oklahoma because of its suitability as a saltwater disposal (SWD) zone. In 2014, the Arbuckle Group received about 68% of the total volumes of saltwater disposal in the state of Oklahoma. Numerous studies show that the rate of saltwater injection into the Arbuckle Group is related to the number and magnitude of earthquakes occurring in Oklahoma. Despite the importance of the Arbuckle Group as a SWD zone and its apparent relationship to induced seismicity, the hydraulic parameters of the Arbuckle Group have not been widely studied or were studied in association with the Simpson Group. Since the mid-20th century, water level fluctuations as a response to earth tides have been used for obtaining aquifer properties of confined and unconfined aquifers. In confined aquifers, earth tides act as a cyclic stress causing water level fluctuations. Time-series analyses of the fluctuations can be used for estimating elastic properties of an aquifer and aquifer hydraulic properties such as specific storage, storage coefficient, transmissivity, porosity, matrix compressibility, hydraulic conductivity, and hydraulic diffusivity. Solid earth tide analysis is a useful tool for calculating rock properties in aquifers or reservoirs where it is not practical to conduct a pumping or a slug test. Confined reservoirs such as the Arbuckle Group respond to small strains and act as volume strain meters. In 2016, a network of inactive Arbuckle SWD wells were instrumented so that pressure fluctuations could be monitored and analyzed. For this thesis research, fluid levels in six of the study wells were evaluated. Fluid levels responded to solid earth tide stresses so that 90-day time series could be analyzed and used to estimate hydraulic and rock properties of the Arbuckle Group in the Anadarko Shelf and the Cherokee Platform geological provinces of Oklahoma. Hydraulic parameters derived from these analyses of these data include median values of 1.39 E-06 m-1 specific storage, 3.69 E-04 storage coefficient, 12.76 m2/d transmissivity, 24% porosity, 3.02 E-07 psi-1 matrix compressibility, 2.21 E-07 m/s hydraulic conductivity, 34.37 mD intrinsic permeability, and 0.69 m2/s hydraulic diffusivity. Values obtained for each of the properties computed in this study differ from the values used in previous studies that modeled the effects of saltwater disposal on subsurface fluid pressure and potential connections to seismicity. These improved values will allow for more realistic predictions of subsurface fluid behavior, pore pressure diffusion, and other geomechanical and seismological processes.
... [Yeck et al., 2015]. Additionally, while most fluids are injected into sedimentary layers [Murray and Holland, 2014], most earthquakes with M>1 have occurred within the crystalline basement at depths of 3-8 km [McNamara et al., 2015;McMahon and Aster, 2016]. This suggests that fluid pressure changes may travel or propagate significant distances from their injection site, and that factors other than injection rate also impact seismic hazard. ...
... Oklahoma's crystalline basement continued to experience tectonic deformation during the late Paleozoic Ouachita and Alleghenian orogenies. These of various ages are presently key exploration targets for oil and gas, wastewater is typically injected into the deeper, underpressured rocks of the Late Cambrian to Ordovician Arbuckle Group [Murray and Holland, 2014]. This group comprises carbonate rocks and sandstone overlying the crystalline basement [Johnson, 1991]. ...
Article
Recent Oklahoma seismicity shows a regional correlation with increased wastewater injection activity but local variations suggest that some areas are more likely to exhibit induced seismicity than others. We combine geophysical and drillhole data to map subsurface geologic features in the crystalline basement, where most earthquakes are occurring, and examine probable contributing factors. We find that most earthquakes are located where the crystalline basement is likely composed of fractured intrusive or metamorphic rock. Areas with extrusive rock or thick (>4 km) sedimentary cover exhibit little seismicity, even in high injection rate areas, similar to deep sedimentary basins in Michigan and western North Dakota. These differences in seismicity may be due to variations in permeability structure: within intrusive rocks, fluids can become narrowly focused in fractures and faults, causing an increase in local pore fluid pressure, whereas more distributed pore space in sedimentary and extrusive rocks may relax pore fluid pressure.
... Other studies of possible induced seismicity include Rooks County, Kansas (Armbruster and others, 1989) and Youngstown, Ohio (Holtkamp and others, 2015). Research has been conducted by the Oklahoma Geologic Survey (OGS) over seismicity in Oklahoma (Darold and others, 2015), injection well data by geologic zone in Oklahoma (Murray, 2014(Murray, , 2015, and a regional study over Nebraska, Kansas, and Oklahoma injection well volumes (Murray and Holland, 2014). This study will focus on injection volumes, pressures, and possible relations to seismicity in south-central Kansas and northern Oklahoma. ...
... The increase in seismicity in Oklahoma coincided with development focused around the Mississippian and Hunton Limestones. The target formations include substantial amounts of coproduced formation brines (Murray and Holland, 2014), which required disposal. Oftentimes, the most economic method of disposal included disposal in adjacent injection wells screened through the karst Arbuckle Group and sometimes deeper into the upper basement. ...
Article
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The Oklahoma Geological Survey (OGS) monitors seismicity throughout the state of Oklahoma utilizing permanent and temporary seismometers installed by OGS and other agencies, while producing a real‐time earthquake catalog. The OGS seismic network was recently added to the Advanced National Seismic System (ANSS) as a self‐supporting regional seismic network, and earthquake locations and magnitudes are automatically reported through U.S. Geological Survey and are part of the ANSS Comprehensive Earthquake Catalog. In Oklahoma, before 2009, background seismicity rates were about 2 M 3.0+ earthquakes per year, which increased to 579 and 903 M 3.0+ earthquakes in 2014 and 2015, respectively. After seismicity peaked, the rate fell to 624, 304, and 194 M 3.0+ earthquakes in 2016, 2017, and 2018, respectively. The catalog is complete down to M 2.2 from mid‐2014 to present, despite the significant workload for a primarily state‐funded regional network. That astonishing uptick in seismicity has been largely attributed to wastewater injection practices. The OGS provides the Oklahoma Corporation Commission, the agency responsible for regulating oil and gas activities within the state, with technical guidance and earthquake products that inform their “traffic‐light” mitigation protocol and other mitigating actions. We have initiated a citizen‐scientist‐driven, educational seismometer program by installing Raspberry Shake geophones throughout the state at local schools, museums, libraries, and state parks. The seismic hazard of the state portends a continued need for expansion and densification of seismic monitoring throughout Oklahoma.
... As can be seen in Fig. 2, the aggregate monthly injection volume in the state gradually doubled from about 80 million barrels/month in 1997 to about 160 million barrels/month in 2013, with nearly all of this increase coming from SWD not EOR. Most of the SWD in central Oklahoma is occurring into the Arbuckle Group that is close to crystalline basement (20). A number of entries in the UIC database had obvious errors, either in the listed monthly injection rates or in the well locations. ...
Article
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Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized earthquakes. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the rates of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent earthquakes. In the areas of seismic activity, the saltwater disposal principally comes from "produced" water, saline pore water that is coproduced with oil and then injected into deeper sedimentary formations. These formations appear to be in hydraulic communication with potentially active faults in crystalline basement, where nearly all the earthquakes are occurring. Although most of the recent earthquakes have posed little danger to the public, the possibility of triggering damaging earthquakes on potentially active basement faults cannot be discounted.
Article
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From 2009 to 2017, parts of Central America experienced marked increase in the number of small to moderate-sized earthquakes. For example, three significant earthquakes (~Mw 5) occurred near Prague, Oklahoma, in the U. S. in 2011. On 6 Nov 2011, an Mw 5.7 earthquake occurred in Prague, central Oklahoma with a sequence of aftershocks. The seismic activity has been attributed to slip on the Wilzetta fault system. This study provides a 3D fully coupled poroelastic analysis (using FLAC3D) of the Wilzetta fault system and its response to saltwater injection in the underpressured subsurface layers, especially the Arbuckle group and the basement, to evaluate the conditions that might have led to the increased seismicity. Given the data-limited nature of the problem, we have considered multiple plausible scenarios, and use the available data to evaluate the hydromechanical response of the faults of interest in the study area. Numerical simulations show that the injection of large volumes of fluid into the Arbuckle group tends to bring the part of the Wilzetta faults in Arbuckle group and basement into near-critical conditions.
Thesis
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Fluid-fault interaction in the subsurface is a critical driver of both natural and induced earthquakes. Fluid-pressure increases inside fault zones lower their frictional resistance to slip and make earthquakes more likely. Inversely, earthquakes also perturb the fluid-pressure field and cause observable changes in groundwater level. This dissertation investigates fluid-fault interaction by studying both groundwater level changes from natural earthquakes and injection-induced earthquakes from fluid injection wells. Chapter 2 quantifies an extremely sensitive water level to distant earthquakes at Devils Hole in southern Nevada. Examining a 24-year water level record, I find the seismic energy density required to initiate both hydroseismogram and coseismic types of water level response is e ~ 10-6 J/m 3, two orders of magnitude smaller than previously documented. This new threshold has implications for the dynamic triggering of earthquakes, as remote earthquakes can lead to pore pressure changes and consequently effective stress changes in fluid-filled fault zones. Chapters 3 through 5 examine the relationship between fluid injection and the unprecedented seismic rate increase in the U.S. mid-continent beginning in 2009. This rate increase occurred in regions where earthquakes were generally uncommon and not predicted by the laws of natural seismicity. Chapter 3 characterizes seismicity and fluid-pressure changes from injection wells in Jones, Oklahoma, showing that high-rate injection wells are likely responsible for the earthquake swarm. The modeled fluid-pressure perturbation propagates throughout the same depth range and tracks earthquakes to distances of 35 km, with a triggering threshold of ~0.07 MPa. Chapter 4 examines the broad-scale relationship between fluid injection and U.S. mid-continent seismicity using a newly assembled injection well database for the central and eastern U.S. Statistical methods find the entire increase in earthquake rate is associated with fluid injection wells. High injection rate wells (>300,000 barrels/month) are statistically much more likely to be associated with earthquakes than lower rate wells. Finally, in Chapter 5, I quantify a novel case of injection-induced seismicity in the Raton Basin of southern Colorado. Hydrogeologic models show injection can induce earthquakes several kilometers below the reservoir injection interval despite a lack of wellhead pressure needed for injection.
Article
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An experiment in an oil field at Rangely, Colorado, has demonstrated the feasibility of earthquake control. Variations in seismicity were produced by controlled variations in the fluid pressure in a seismically active zone. Precise earthquake locations revealed that the earthquakes clustered about a fault trending through a zone of high pore pressure produced by secondary recovery operations. Laboratory measurements of the frictional properties of the reservoir rocks and an in situ stress measurement made near the earthquake zone were used to predict the fluid pressure required to trigger earthquakes on preexisting fractures. Fluid pressure was controlled by alternately injecting and recovering water from wells that penetrated the seismic zone. Fluid pressure was monitored in observation wells, and a computer model of the reservoir was used to infer the fluid pressure distributions in the vicinity of the injection wells. The results of this experiment confirm the predicted effect of fluid pressure on earthquake activity and indicate that earthquakes can be controlled wherever we can control the fluid pressure in a fault zone.
Geologic provinces of Oklahoma: Oklahoma Geological Survey Open-File Report 5-95
  • R A Northcutt
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Northcutt, R.A., and J.A. Campbell, 1995, Geologic provinces of Oklahoma: Oklahoma Geological Survey Open-File Report 5-95, scale 1:750,000.
Report on Oil and Natural Gas Activity Within the State of Oklahoma: Technical Services Department, Oil and Gas Conservation Commission
OCC, 2012, 2011 Report on Oil and Natural Gas Activity Within the State of Oklahoma: Technical Services Department, Oil and Gas Conservation Commission. http://digitalprairie. ok.gov/cdm/ref/collection/stgovpub/ id/168874
Monthly injection volumes for Class II Underground Injection Control (UIC) wells in Kansas
  • A Snider
Snider, A., 2013, unpublished data, Monthly injection volumes for Class II Underground Injection Control (UIC) wells in Kansas, 2011 and 2012: Topeka, Kansas, Oil and Gas Conservation Division, Kansas Cor-
Induced Seismicity Potential in Energy Technologies
NRC, 2012, Induced Seismicity Potential in Energy Technologies, Washington, DC, National Academy of Sciences, 225p.