Estimated Ultimate Recovery (EUR) Study of 5,000 Marcellus Shale Wells in Pennsylvania. February 2018 Update Gary S. Swindell, P.E., Consulting Petroleum Engineer, Dallas, Texas http://gswindell.com Copyright 2018, Gary S. Swindell. Summary This study summarizes the results of an updated and expanded evaluation of the estimated ultimate recovery (EUR) for all horizontal Marcellus Shale completions from 2008 through 2014 in Pennsylvania. Individual well rate vs. time plots using publically available production data through June 2017 were used to forecast the EUR of 4,936 wells. The primary objective was to determine the distribution of EUR. Although data is also available for the 2015-2017 well completions, the decline behavior is not believed to be sufficiently established for reliable projections. For 4,936 horizontal wells with enough history to forecast a decline profile, the estimated ultimate recovery across the whole state averages 6.2 billion cubic feet equivalent (Bcfe) per well with a median of 5.0 Bcfe. The results vary considerably by region in six counties in the Northeast part of Pennsylvania, the average is 7.2 Bcfe per well and in Wyoming County the mean EUR is 12 Bcfe. In that Northeast region there are a number of wells exceeding 20 Bcfe EUR. (Lease condensate was converted to an equivalent gas volume using a price ratio of 20 thousand cubic feet (Mcf) per barrel). The data shows that apparent operational changes across the area, primarily added take-away capacity and compression, have significantly improved well performance since the last study in early 2016. Furthermore, many wells have shown more hyperbolic behavior than forecast in the earlier studies. A regional breakdown, dividing the state into six areas, Northeast, Northwest, West Central, Mountain, Green-Fayette, and Washington, was made to analyze well performance in a more local way. (Fig. 3 in the appendix shows the location of the wells in the study and the regional divisions.) Charts and tables are used to show the results rather than a paragraph format.
2 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018 Fig. 1 Total Pennsylvania Marcellus gas production vintaged by year. 7000 Pennsylvania Marcellus Producing Wells Vintaged by year of first production 6000 Producing Wells 5000 4000 3000 2000 1000 0 08 09 10 11 12 13 14 15 16 17 By comparison, Texas active gas well count is 70,000 Fig 2. Pennsylvania Marcellus Horizontal Well Count.
Gary S. Swindell, Petroleum Engineering Marcellus Study 2018 3 Summary of Projected EUR by County Number of Study wells County Average EUR - BCFe per Well Avg Gas Cum Prod ~8/2017 - MCF 35 ALLEGHENY 4.98 3,137,435 42 ARMSTRONG 4.49 2,144,871 2 BEAVER 3.76 2,331,868 6 BLAIR 1.15 598,714 753 BRADFORD 7.71 4,169,130 180 BUTLER 4.96 1,859,820 10 CAMERON 1.61 938,401 8 CENTRE 2.26 1,333,290 9 CLARION 2.58 1,156,238 74 CLEARFIELD 1.95 1,145,644 44 CLINTON 3.37 2,014,928 30 ELK 3.12 1,583,605 114 FAYETTE 3.50 1,873,406 4 FOREST 0.92 414,056 452 GREENE 6.30 3,623,124 1 HUNTINGDON 0.62 435,314 21 INDIANA 2.66 1,620,088 22 JEFFERSON 3.33 1,406,866 4 LAWRENCE 2.25 1,164,369 651 LYCOMING 5.55 3,238,274 35 MC KEAN 2.63 1,468,163 1 MERCER 1.44 760,990 29 POTTER 2.79 1,515,148 10 SOMERSET 1.86 1,213,625 47 SULLIVAN 11.52 5,587,276 712 SUSQUEHANNA 9.20 5,378,011 500 TIOGA 4.04 2,323,474 1 VENANGO 1.22 668,327 824 WASHINGTON 5.28 2,374,948 170 WESTMORELAND 4.02 2,303,156 145 WYOMING 11.70 6,299,625
4 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018 Fig. 3 The wells and the regions used in the study.
Gary S. Swindell, Petroleum Engineering Marcellus Study 2018 5 NORTHEAST REGION Bradford, Lycoming, Sullivan, Susquehanna, Tioga, Wyoming counties NORTHWEST REGION Cameron, Elk, Forest, McKean and Potter counties
6 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018 WEST CENTRAL REGION Allegheny, Armstrong, Beaver, Butler, Clarion, Indiana, Jefferson, Westmoreland GREEN-FAYETTE REGION Greene and Fayette counties
Gary S. Swindell, Petroleum Engineering Marcellus Study 2018 7 WASHINGTON COUNTY MOUNTAIN REGION Blair, Centre, Clearfield, Clinton, Somerset counties
8 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018
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10 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018
Gary S. Swindell, Petroleum Engineering Marcellus Study 2018 11 For about 2,200 wells of the almost 5,000 wells in the study there was readily available perforation information. The perforated interval was used as a proxy for horizontal length. Correlations of EUR to this horizontal length proxy are below by region.
12 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018 For about 2,200 wells of the almost 5,000 wells in the study there was readily available perforation information. The perforated interval was used as a proxy for horizontal length. Correlations of EUR to this horizontal length proxy are below by region.
Gary S. Swindell, Petroleum Engineering Marcellus Study 2018 13 For about 2,200 wells of the almost 5,000 wells in the study there was readily available perforation information. The perforated interval was used as a proxy for horizontal length. Correlations of EUR to this horizontal length proxy are below by region.
14 Gary S. Swindell, Petroleum Engineering Marcellus EUR Study 2018 For about 2,200 wells of the almost 5,000 wells in the study there was readily available perforation information. The perforated interval was used as a proxy for horizontal length. Correlations of EUR to this horizontal length proxy are below by region.