The document outlines the importance of diagnostic plots for reservoir analysis, focusing on time regions and flow regimes that impact pressure response. It details various flow scenarios including transient, pseudo-steady, and steady state, as well as factors influencing pressure behavior over time. Additionally, it emphasizes the significance of this information for Schlumberger's engineers in effectively utilizing reservoir modeling software and enhancing stimulation design.

1. 1
Reservoir and Geometric Flow
Regimes Diagnostic Plot
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2. 2
Outline
1. Importance to Schlumberger
2. Time regions.
3. Flow regimes.
4. Factors that affect pressure response
in early time.
5. Boundaries that affect pressure
response in late time.

3. 3
Objectives
1. Describe the diagnostic plot.
2. State the importance to Schlumberger
3. Identify the Time regions.
4. Identify the Flow regimes and their
characteristic slope.
5. List 3 factors that affect pressure
response in early time.
6. List 3 boundaries that affect pressure
response in late time.

4. 4
Importance to
Schlumberger Engineers
1. Allow us to use the proper Reservoir
Model in the WELLTESTTM software
2. Improve our stimulation design.

5. 5
Reservoir Flow
Regimes
1. Transient flow: Pressure disturbance has not
reached the reservoir boundary and the reservoir
seems infinite. Infinite-acting radial flow (IARF)
occurs during this time.
dP/dt = variable
2. Pseudo-steady state: Effects of the reservoir
boundary are felt. Pressure starts depleting,
however, rate remains same as long as the pressure
drawdown remains the same.
dP/dt = constant
3. Steady state: Pressure distribution uniform
throughout the reservoir and the average reservoir
pressure does not change with time.
dP/dt = 0

6. 6
The Log-Log Diagnostic Plot:
Pressure Change, Derivative vs. Δt
Elapsed time,
hrs
Pressure
change,
derivative,
psi

7. 7
Time Regions on the Diagnostic Plot
Elapsed time,
hrs
Early-time
region
Middle-
time
region
Late-time
region
Pressure
change,
derivative,
psi

8. 8
Geometric Flow Regimes
⮚ Common geometric shapes
⮚ Different flow patterns may appear at
different times in a single test
⮚ Flow regimes follow sequence within
model

9. 9
Volumetric Behavior

10. 10
Radial Flow

11. 11
Linear Flow

12. 12
Bilinear Flow

13. 13
Spherical Flow

14. 14
Flow Regimes on the
Diagnostic Plot
Wellbore
storage Spherical flow??
Radial
flow Recharg
e
PSS?

15. 15
Flow Regimes
and the
Diagnostic
Plot:
RSB

16. 16
Exercise 1: Flow Regimes and the Diagnostic
Plot
Type of well, geology…?

17. 17
Fracture Linear
Bilinear
Formation Linear
Elliptical
Pseudoradial
WBS
⮚ Unit slope in all wells.
⮚ ½ slope but normally hidden during
WBS
⮚ ¼ slope in finite cond. Fracs. wkf
estimated if k is known
⮚ ½ slope in infinite cond. fracs. xf
estimated if k is known.
⮚ Transitional period
⮚ 0 slope seen in infinite cond. fracs.
Estimate k and s. Skin factor used to
estimate xf

18. 18
Objectives
⮚ Describe the diagnostic plot.
⮚ State the importance to Schlumberger
⮚ Identify the Time regions.
⮚ Identify the Flow regimes and their
characteristic slope.
⮚ List 3 factors that affect pressure response in
early time.
⮚ List 3 boundaries that affect pressure response
in late time.
⮚ Questions and Comments!