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.
Fig 2. Pennsylvania Marcellus Horizontal Well Count.
0
1000
2000
3000
4000
5000
6000
7000
Jan
-0
8
Jan
-0
9
Jan
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0
Jan
-1
1
Jan
-1
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Pro
du
cin
g W
ell
s
Pennsylvania Marcellus Producing WellsVintaged by year of first production
By comparison, Texas active gas well
count is 70,000
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
Gary S. Swindell, Petroleum Engineering – Marcellus Study 2018 9
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.
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