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Petroleum Engineering 324 — Well Performance

Final Project — Analysis of Water Well Test Data (Texas A&M University)

24 April 2001 — Due: Tuesday 8 May 2001

Orientation:

This final project involves the analysis of the water well test data that were taken as part of a class project on 21 March 2001. You are required to provided detailed reviews of four (4) classic papers on well test analy-sis.

All of the pertinent project data are located at:

The following files are included:

MS Word File:

P324_01A_FinPrj_WtrWellTst.doc

MS Excel File: (all pump test data and data functions)

010321_P324_Pump_Test_Stdt.xls

Adobe .pdf Files: (for paper reviews)

SPE_05878_Ramey_Practl_WTA.pdf

SPE_10041_Ramey_DstAth_WTA.pdf

SPE_20592_Ramey_AdvPrc_WTA.pdf

SPE_28008_Kamal_ResMgt_WTA.pdf

You are responsible for all data plots, analyses, interpretations, and reporting. You are not to share work of any type — this is an exercise to demonstrate your expertise and diligence in creating a comprehensive engi-neering report.

Grading Rationale:

You are strongly encouraged to work in groups, but you must provide your own work and you must write your own report. "Sharing" various sections of work will be considered scholastic dishonesty and will be rewarded with an "F" grade — as provided for in the University Regulations (now titled Student Rules).

The concept of grading for this project is that an "average" effort should yield a "C" grade—hence, the grad-ing scheme is quite demanding and somewhat subjective — but it is consistent, and you should be able to predict your performance by your level of effort. In short, this project is an "attitude" test — you must give your very best effort. The overall objective is for you to demonstrate your mastery of the subject matter in a problem typical (at least in scope) of what you will encounter in industry.

Table 1 — Grading Policy

Score / Description / Criteria
A / Outstanding / Perfection.
B+ / Very Good / No major technical errors.
Near perfect work.
B / Good / No major technical errors.
Much more effort than required.
C+ / Above Average / Minor technical errors.
More effort than required.
C / Average / Minor technical errors.
Effort exactly what was required.
D+ / Below Average (Fair) / Minor technical errors.
Effort less than required.
D / Below Average (Poor) / Significant technical errors.
Effort less than required/poor effort.
F / Unacceptable / Significant technical errors
Poor/unacceptable effort.

Petroleum Engineering 324 — Well Performance

Final Project — Analysis of Water Well Test Data (Texas A&M University)

24 April 2001 — Due: Tuesday 8 May 2001

Field Project: Analysis of Water Well Test Data (Texas A&M University)

This problem consists of a pressure drawdown/buildup test sequence performed on a pumping WATER well (our campus water well). There are no "tricks" involved — this should be a straightforward analysis/inter-pretation sequence. Be sure to perform all analyses—and cross-check/double-check your work whenever possible (i.e., using different techniques, as well as comparing results from the drawdown and buildup analyses).

Given Data:

The attached data were taken from a pressure drawdown/buildup test sequence performed on our campus water well. The reservoir interval is a water sand at about 450 ft — the well is not stimulated and should not be damaged. The reservoir should be assumed to be homogeneous and infinite-acting.

Reservoir properties:

=0.25rw=0.36 ftct=6.5x10-6 psia-1h=23 ft

Water properties:

Bw=1.0 RB/STBw=1.0 cp

Production parameters:

Event / Duration
of Event
(hr) / Pressure at start
of Event
(psia) / Water
Flowrate
(STB/D)
1.Drawdown Test / 1.9389 / pi=147.29 / 60
2.Buildup Test / 2.8792 / pwf(t=0)=139.32 / 0

Pressure Test Data:

All of the pressure drawdown/pressure buildup test data and associated data functions are provided in an MS Excel file (010321_P324_Pump_Test_Stdt.xls) which can be obtained from the following web location:

Summary Plots: (Drawdown/Buildup Test Sequences — for orientation only (do not use for analysis))

Petroleum Engineering 324 — Well Performance

Final Project — Analysis of Water Well Test Data (Texas A&M University)

24 April 2001 — Due: Tuesday 8 May 2001

Required:

You are required to provide a complete and comprehensive analysis/interpretation of all of the well test data that are provided. You must provide your own plots, calculations, commentary, descriptions, etc. It is acceptable to use a graphics product such as MS Excel for most of the plots, BUT you must plot the pressure test data functions by hand on the log-log grid paper provided — this is required to achieve the proper scaling for type curve matching.

Drawdown Case:

Given the pressure drawdown data provided, you are to estimate the following:

Preliminary log-log analysis:

a.The wellbore storage coefficient, Cs.

b.The formation permeability, k.

Cartesian analysis of "early" time (wellbore storage dominated) data:

a.The pressure at the start of the test, pi.

b.The wellbore storage coefficient, Cs.

Semilog analysis of "middle" time (radial flow) data:

a.The formation permeability, k.

b.The near-well skin factor, s.

c.The radius of investigation, rinv, at the end of radial flow.

Type curve analysis:

a.The formation permeability, k.

b.The near-well skin factor, s.

c.The wellbore storage coefficient, Cs.

Drawdown Case — Results:

Preliminary Log-Log Analysis:

Wellbore storage coefficient, Cs= ______RB/psia

Formation permeability, k= ______md

Cartesian Analysis: Early Time Data

Pressure at start of test, pi= ______psia

Wellbore storage coefficient, Cs= ______RB/psia

Semilog Analysis:

Formation permeability, k= ______md

Near-well skin factor, s= ______

Radius of Investigation, rinv(end of radial flow)= ______ft

Type Curve Analysis:

Formation permeability, k= ______md

Near-well skin factor, s= ______

Wellbore storage coefficient, Cs= ______RB/psia

Petroleum Engineering 324 — Well Performance

Final Project — Analysis of Water Well Test Data (Texas A&M University)

24 April 2001 — Due: Tuesday 8 May 2001

Required: (continued)

Buildup Case:

Given the pressure drawdown data provided, you are to estimate the following:

Preliminary log-log analysis:

a.The wellbore storage coefficient, Cs.

b.The formation permeability, k.

Cartesian analysis of "early" time (wellbore storage dominated) data:

a.The pressure at the start of the test, pwf(t=0).

b.The wellbore storage coefficient, Cs.

Semilog analysis of "middle" time (radial flow) data:

a.The formation permeability, k.

b.The near-well skin factor, s.

c.The radius of investigation, rinv, at the end of radial flow.

d.The extrapolated pressure, p*.

Cartesian analysis of "late" time (boundary-dominated) data: ("Muskat Plot")

a.Average reservoir pressure, pavg.

Type curve analysis:

a.The formation permeability, k.

b.The near-well skin factor, s.

c.The wellbore storage coefficient, Cs.

Buildup Case — Results:

Preliminary Log-Log Analysis:

Wellbore storage coefficient, Cs= ______RB/psia

Formation permeability, k= ______md

Cartesian Analysis: Early Time Data

Pressure at start of test, pwf(t=0)= ______psia

Wellbore storage coefficient, Cs= ______RB/psia

Semilog Analysis: (MDH and Horner analysis)

Formation permeability, k= ______md

Near-well skin factor, s= ______

Radius of Investigation, rinv (end of radial flow)= ______ft

Extrapolated pressure, p* (from Horner analysis)= ______psia

Cartesian Analysis: Late Time Data ("Muskat Plot")

Average reservoir pressure, pavg= ______psia

Type Curve Analysis:

Formation permeability, k= ______md

Near-well skin factor, s= ______

Wellbore storage coefficient, Cs= ______RB/psia

Petroleum Engineering 324 — Well Performance

Final Project — Analysis of Water Well Test Data (Texas A&M University)

24 April 2001 — Due: Tuesday 8 May 2001

Required: (continued)

Paper Reviews:

You are to provide a critical and detailed review (at least 1 page) for the following paper(s):

Ramey, H.J., Jr.: "Practical Use of Modern Well Test Analysis," Paper SPE 5878 presented at the 1976 SPE Improved Oil Recovery Symposium, Tulsa, OK, 22-24 March.

Ramey, H.J., Jr.: "Distinguished Transient Testing," JPT (1982), 1407-1415.

Ramey, H.J., Jr.: "Advances in Practical Well-Test Analysis," paper SPE 20592 presented at the 1992 SPE Annual Technical Conference and Exhibition held in New Orleans, LA, September, 23-26.

Kamal, M.M., Freyder, D.G., Murray, M.A.: "Use of Transient Testing in Reservoir Manage-ment," paper 28008 presented at the University of Tulsa Centennial Petroleum Engineering Symposium held in Tulsa, OK, 29-31 August 1994.

These papers can be obtained from the following web location:

The papers are provided as Adobe Acrobat .pdf files.

SPE_05878_Ramey_Practl_WTA.pdf

SPE_10041_Ramey_DstAth_WTA.pdf

SPE_20592_Ramey_AdvPrc_WTA.pdf

SPE_28008_Kamal_ResMgt_WTA.pdf

For each paper you are to address the following questions: (Type or write neatly)

Problem:

—What is/are the problem(s) solved?

—What are the underlying physical principles used in the solution(s)?

Assumptions and Limitations:

—What are the assumptions and limitations of the solutions/results?

—How serious are these assumptions and limitations?

Practical Applications:

—What are the practical applications of the solutions/results?

—If there are no obvious "practical" applications, then how could the solutions/results be used in practice?

Discussion:

—Discuss the author(s)'s view of the solutions/results.

—Discuss your own view of the solutions/results.

Recommendations/Extensions:

—How could the solutions/results be extended or improved?

—Are there applications other than those given by the author(s) where the solution(s) or the concepts used in the solution(s) could be applied?

Petroleum Engineering 324 — Well Performance

Final Project — Analysis of Water Well Test Data (Texas A&M University)

24 April 2001 — Due: Tuesday 8 May 2001

Required: (continued)

Reporting Guidelines:

a.You are to prepare a comprehensive report of your analyses — this report should be no less than 3 (three) pages of narrative discussion (not including plots, equations, etc.). You are to document your work com-pletely, as well as describe your analysis procedures and results in full detail.

b.You should prepare your results in a tabular format — this will make comparisons and referencing of different results much more straightforward.

c.You must provide your own plots. It is acceptable to use a graphics product such as MS Excel for most of the plots, BUT you must plot the pressure test data functions by hand on the log-log grid paper provided — this is required to achieve the proper scaling for type curve matching.

d.You are strongly encouraged to have someone proofread your report — in particular, it would be best if the reviewer knows nothing about the subject, but is reviewing the report as an editor, with a focus on style, content, and format — rather than technical details.

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