Summary of Publicly Available Production Data for the Devonian Berea Sandstone Play, Eastern Kentucky* Brandon C. Nuttall 1 Search and Discovery Article #10895 (2016)** Posted December 12, 2016 *Adapted from oral presentation given at AAPG 2016 Eastern Section Meeting, Lexington, Kentucky, September 25-27, 2016 **Datapages 2016 Serial rights given by author. For all other rights contact author directly. 1 Kentucky Geological Survey, University of Kentucky, 504 Rose St., Lexington, KY 40506 (bnuttall@uky.edu) Abstract The Devonian Berea Sandstone was discovered in Lawrence County in the late 1870's. Major Berea development occurred in the 1920's and in the late 1950's with the advent of waterflooding. In the 1980's, Section 29 tight formation tax credits temporarily made the Berea interesting again. Recently, horizontal drilling and slickwater fracture stimulations have led to a Berea renaissance with Lawrence County now the leading oil-producing county in the state. Berea wells completed since 1997 were selected that had enough periods of publicly available production data for analysis to characterize the initial performance of the wells. The maximum reported monthly production rate, first year cumulative production volume, and production decline were modeled. For each well with sufficient data, the better fit of an exponential or hyperbolic decline curve was used to characterize production trends. A gas production index was defined as the ratio of gas production to the sum of oil and gas production on a barrels of oil equivalent basis and used to map regional trends in oil- and gas-prone production. Well performance was divided into three classes based on the first year cumulative production at the 25th and 75th percentiles. Typical oil and gas decline curves for each of these groups exhibit significant differences relative to predicted future performance. Based on limited historic production data, Berea oil producers out-perform typical Kentucky wells. The Berea in Greenup and Lawrence counties is oil-prone while Pike County exhibits a significant wet gas-prone area with some wells reporting varying amounts of oil production.
References Cited Fetkovich, M.J., E.J. Fetkovich, and M.D. Fetkovich, 1996, Useful Concepts for Decline-Curve Forecasting, Reserve Estimation, and Analysis: Society of Petroleum Engineers, Reservoir Engineering, SPE-28628-PA, February 1996, p. 13-22. Nuttall, B.C., 2014, Review of Kentucky Oil and Gas Production, 2010: Lexington, Kentucky, Kentucky Geological Survey, Series XII, Information Circular 30, 16 p., http://kgs.uky.edu/kgsweb/olops/pub/kgs/ic30_12.pdf, Website accessed December 2016. Nuttall, B.C., 2007, Decline Object: A Python Script to Find the Best Fit Hyperbolic or Exponential Decline Parameters: Lexington, Kentucky, Kentucky Geological Survey, http://www.uky.edu/kgs/emsweb/devsh/production/decline_obj.py, Website accessed December 2016. Pilgrim, M., 2004, Dive into Python: New York, Apress Publishing Company, 413 p., http://www.diveintopython.net, Website accessed December 2016.
Summary of Publicly Available Production Data for the Devonian Berea Sandstone Play, Eastern Kentucky Brandon C. Nuttall Eastern Section AAPG, Lexington, Kentucky, 26-Sep-2016
ray General Stratigraphy East Kentucky Berea c.. c 0 c: 0 rg.- 0- c: 0- > CII 0 '" CII 111..t:: III IV.s=.. <II IV 0.- g..t:: c 0 IV iii 15 Cleveland Upper ~ Huron iii '".s= <II c ill'.s= u Lower Huron 0 " Olentangy Shale Rh inestreet Shale
Heterogeneity and Soft Sediment KY 10, near Garrison, Lewis County, Kentucky
Horizontal Wells by Year Horizontal Wells 350 300 250 200 150 100 50 1,640 permitted 40 Total Berea oil wells 3000 2500 2000 1500 1000 500 Total Permits Issued 0 1979 1990 1991 1992 1993 1995 1999 2000 2001 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 OIL O&G GAS D&A Other LOC Permits 0
2015 Oil Production: 2.8 MMbo Million Barrels 9 8 7 6 5 4 3 2 1 0 75% increase 2011 to 2014 1980 1985 1990 1995 2000 2005 2010 2015 63 Kentucky counties, 58 percent from eastern Kentucky
Significant Increase in Berea Oil production (barrels) x 100000 8 7 6 5 4 3 2 1 Production 0 2000 2005 2010 2015 Greenup Lawrence Henderson Union
Daily Average vs 2010 Study 100% 75% 50% 25% 0% 0.9 0.01 0.1 1 10 100 1000 Bo/d Nuttall, 2014, KGS Ser 12, IC 30 All oil wells in 2010 public data set 26 Greenup & Lawrence Horizontal wells At least 1 year of data
Kentucky Wells with Devonian Berea Completion Earliest wells: 1879 to 1890 s in Johnson Co., and Blaine area of Lawrence Co.
Lawrence County Development History Annual oil production (barrels) Thousands 750 625 500 375 250 125 1 st major fields Waterfloods Tight sands Horizontal wells slickwater fracks 120 100 80 60 40 20 Annual number of wells completed 0 0 1920 1940 1960 1980 2000 2020 Oil (bbl) Wells Completed
GREEN CARTER - 0 Devonian Berea Activity Status Historic fields.. Oil Consolidated BOY Oil and gas Oil field - - @ Gas Gas field - - Dry Waterflood Permitted 0 Horizontal well, ~ I OTT 0 0 LAW,, @ C@ C& @ @ 024 8 12 16 N A -=-=.. _~==.. _ Miles ~NSON ~ o~ 0 - -
Public Data Selection Criteria Oilandgas.ky.gov 805 KAR 1:180 Well was completed Berea only (no commingling) After 1997 (early-time data available) Oil or gas production values >0 for at least 1 month (no shut-in)
Well Types Number of wells 25 20 15 10 5 Horizontal Vertical 0 Jan-99 Jan-00 Jan-01 Jan-02 Jan-03 Jan-04 Jan-05 Jan-06 Jan-07 Jan-08 Jan-09 Jan-10 Jan-11 Jan-12 Jan-13 Wells with production data
Decline Models Begin at period of maximum reported monthly production At least 11 months of data following Correlation coefficient, r 2, at least 0.47 Exponential qq tt = qq ii ee DD iitt qq tt = Hyperbolic qq ii 11 bbdd ii tt 11 bb www.uky.edu/kgs/emsweb/devsh/production/decline_obj.py
Maximum reported monthly production rate Sample data At least 12 periods
GGGGGG = GGGGGG MMMMMM OOOOOO bbbbbb No oil then what? GOR & GPI Gas Production Index GGGGGG = 00. 11111111 GGGGGG MMMMMM OOOOOO bbbbbb + 00. 11111111 GGGGGG MMMMMM Ratios on boeq basis Compare cumulative production data 0 to < 0.25 oil well <= 2Mcf/bbl (stripper gas) 0.945 to 1 gas well >= 100 Mcf/bbl
Gas Production Index Number of wells 80 60 40 20 Oil Gas 0 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 GREENUP JOHNSON LAWRENCE PIKE
Regional Distribution of Production Data
Production Data Set 139 wells PIKE 50% LAWRENCE 31% JOHNSON 2% Horizontal GREENUP 17% Vertical 0 50 100 Number of wells
Pike Co. r 2 =0.98 Greenup Co. r 2 =0.87 Lawrence Co. r 2 =0.03 Greenup Co. r 2 =0.002
Oil Production Production data 88 wells At least 12 months 32 wells (Cumulative graph) Decline significant (r 2 > 0.47) 10 wells (Type declines)
Short Term Oil Well Performance Cumulative barrels (1 st year) 32 wells 100,000 10,000 1,000 100 75th 25th Median 2,850 bo y = 6.1297x 0.9917 R² = 0.953 10 100 1,000 10,000 Maximum reported monthly rate (barrels) Horizontal 25th 331 Vertical 75th 1,786 5,750 1,290
Short Term Oil Well Performance Cumulative barrels (1 st year) 32 wells 100,000 10,000 1,000 100 75th 25th Type 3 Type 2 Type 1 y = 6.1297x 0.9917 R² = 0.953 10 100 1,000 10,000 Maximum reported monthly rate (barrels) Horizontal 25th 331 Vertical 75th 1,786 5,750 1,290
Typical Oil Declines Rate (barrels/mo) 3,000 2,500 2,000 1,500 1,000 500 0 Average 21 bo/d 3 11 bo/d 2 1 6 bo/d 0 6 12 18 24 30 Time (Month) Type 1 Type 2 Type 3 Median decline within each type class
Greenup County... Cumulative ~~... ~ Production Producti 10,902 11 12,805 3,506 4 7,456 7,709 7,471 CARTn Oil bbl mvd Production comparison BOEQ1yr e 10,000 _ AvgDa ilyo il D AvgDailyGas Horizontal well N A 8 12 16 oo::=-c=--== Miles 7,826 7,826 3,686 8,320 LAWR NCI MORGAN Gas boeq JOI NSON 1 st year oil and gas total (boeq)
Lawrence County Cumulative Production 1 st year oil and gas total (boeq) Oil bbl Gas boeq
Gas Production Production data 128 wells At least 12 months 98 wells (Cumulative graph) Decline significant (r 2 > 0.47) 74 wells (Type declines)
Short Term Gas Well Performance Cumulative Mcf (1st Year) 98 wells 1,000,000 100,000 10,000 75% 25% Median 50.2 MMcf 25% 1,501 y = 7.823x 0.9743 R² = 0.9591 1,000 100 1,000 10,000 100,000 Maximum reported monthly rate (Mcf) Horizontal Vertical 75% 9,482 82,706 13,345
Short Term Gas Well Performance Cumulative Mcf (1st Year) 98 wells 1,000,000 100,000 10,000 75% 25% Type 1 Type 3 Type 2 25% 1,501 y = 7.823x 0.9743 R² = 0.9591 1,000 100 1,000 10,000 100,000 Maximum reported monthly rate (Mcf) Horizontal Vertical 75% 9,482 82,706 13,345
Typical Gas Declines Rate (MMcf/mo) 18 16 14 12 10 8 6 4 2 0 1 2 3 0 6 12 18 24 30 Type 1 Type 2 Type 3 Average 5.7 MMcf/mo 2.9 MMcf/mo 0.6 MMcf/mo Median decline within each type class
Pike County Cumulative oil production by well ranges from 1 to 2,394 barrels Oil bbl Gas boeq
GPI 0.25 Oil prone Greenup Lawrence Martin? Gas prone Pike
Synthesis Limited historic production data Most recent public data are 2 years old Few oil wells with >12 months of data Berea oil producers out-perform typical Kentucky well Horizontal, Greenup and Lawrence Counties Oil-prone areas: Greenup and Lawrence Gas-prone area: Pike County Wet gas includes reported oil production
Implication There may be additional areas with old, relatively shallow producing wells where horizontal drilling and modern completions could revive that production. If the price is right
Thanks Bnuttall@uky.edu www.uky.edu/kgs
References Fetkovich, M.J., Fetkovich, E.J., and Fetkovich, M.D., 1996, Useful concepts for decline-curve forecasting, reserve estimation, and analysis: Society of Petroleum Engineers, Reservoir Engineering, SPE-28628-PA, February 1996, p. 13-22. Nuttall, B.C., 2007, Decline object: a Python script to find the best fit hyperbolic or exponential decline parameters: Lexington, Kentucky, Kentucky Geological Survey, URL http://www.uky.edu/kgs/emsweb/devsh/production/decline_obj.py. Nuttall, B.C., 2014, Review of Kentucky oil and gas production, 2010: Lexington, Kentucky, Kentucky Geological Survey, Series XII, Information Circular 30, 16 p., URL http://kgs.uky.edu/kgsweb/olops/pub/kgs/ic30_12.pdf. Pilgrim, M., 2004, Dive into Python: New York, Apress Publishing Company, 413 p., URL http://www.diveintopython.net.