Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Orientation : DaPrat, et al, paper SPE 13054 Discussion : This homework concerns the analysis of pressure drawdown and buildup test data for a well in western Venezuela (Well Mach 3X — 2 tests total, see attached paper by DaPrat, et al). The associated plots (Cartesian, semilog, and log-log data plots) are attached, as well as the appropriate type curves for dual porosity systems. As noted in the paper, these well tests are NOT contemporary — i.e., do not "tie" the pressure drawdown and pressure buildup tests to each other, use the production history as specified for the pressure buildup test. In short — ANALYZE THESE DATA SEPARATELY! References : 1. DaPrat, G., Mannucci, J., Prado, L., and Millan, E.: "Use of Pressure Transient Testing to Evaluate Fractured Reservoirs in Western Venezuela," paper SPE 13054 presented at the 1984 SPE Annual Conference and Technical Exhibition, Houston, TX, 16-19 September, 1984. Type Curve Analysis Relations : Naturally Fractured Reservoir : (p wD ' vs. t D λ/(1-ω) format, "Onur, et al " type curves) Formation Permeability : ] or [ ] or [ 2 141 MP MP ' wD wD ' p ' p p p h qB . k Δ Δ = μ Dimensionless Fracture Storativity : ω is taken from the type curve match Dimensionless Interporosity Flow Parameter : )] 1 /( [ ] [ 0002637 0 ) 1 /( 1 2 MP D MP w t t t r c k . ω λ φμ ω λ − = − Note: The Cartesian and semilog data analysis techniques are used in exactly the same manner for natural-ly fractured (i.e., dual porosity) reservoirs as for homogeneous reservoir systems. There are other interpretation techniques for the semilog analysis of pressure data from naturally fractured reser-voirs (e.g., those techniques discussed in the second edition of the Lee, et al text), but for the purpose of this homework, you should only use "conventional" semilog (and Cartesian) data analy- sis methods. Required : 1. You are to analyze the well test data in the paper by DaPrat, et al. in as complete detail as possible. The required data, plots, and instructions are attached. Notes : a. Various type curves are provided in a 1 inch-by-1 inch format in this handout — these type curves should be sufficient for your analysis. b. You are to provide a comprehensive HAND ANALYSIS of these test data — type curves are provided for hand analysis..
31
Embed
Naturally Fractured Reservoirs (DaPrat, et al Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Orientation: DaPrat, et al, paper SPE 13054 Discussion: This homework concerns the
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054)
Orientation: DaPrat, et al, paper SPE 13054
Discussion:
This homework concerns the analysis of pressure drawdown and buildup test data for a well in western Venezuela (Well Mach 3X — 2 tests total, see attached paper by DaPrat, et al). The associated plots (Cartesian, semilog, and log-log data plots) are attached, as well as the appropriate type curves for dual porosity systems. As noted in the paper, these well tests are NOT contemporary — i.e., do not "tie" the pressure drawdown and pressure buildup tests to each other, use the production history as specified for the pressure buildup test. In short — ANALYZE THESE DATA SEPARATELY!
References:
1. DaPrat, G., Mannucci, J., Prado, L., and Millan, E.: "Use of Pressure Transient Testing to Evaluate Fractured Reservoirs in Western Venezuela," paper SPE 13054 presented at the 1984 SPE Annual Conference and Technical Exhibition, Houston, TX, 16-19 September, 1984.
Type Curve Analysis Relations:
Naturally Fractured Reservoir: (pwD' vs. tDλ/(1-ω) format, "Onur, et al " type curves)
Formation Permeability:
]or [
]or [ 2141MP
MP'wDwD'p'p
pph
qB.kΔΔ
=μ
Dimensionless Fracture Storativity:
ω is taken from the type curve match
Dimensionless Interporosity Flow Parameter:
)]1/([
][ 00026370)1/(
12 MPD
MP
wt tt
rc
k.ωλφμωλ −
=−
Note: The Cartesian and semilog data analysis techniques are used in exactly the same manner for natural-ly fractured (i.e., dual porosity) reservoirs as for homogeneous reservoir systems. There are other interpretation techniques for the semilog analysis of pressure data from naturally fractured reser-voirs (e.g., those techniques discussed in the second edition of the Lee, et al text), but for the purpose of this homework, you should only use "conventional" semilog (and Cartesian) data analy-sis methods.
Required:
1. You are to analyze the well test data in the paper by DaPrat, et al. in as complete detail as possible. The required data, plots, and instructions are attached.
Notes:
a. Various type curves are provided in a 1 inch-by-1 inch format in this handout — these type curves should be sufficient for your analysis.
b. You are to provide a comprehensive HAND ANALYSIS of these test data — type curves are provided for hand analysis..
2
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Cinco-Samaniego" Type Curve
"Cinco-Samaniego" Type Curve: pwD and pwD' vs. tDxf — Various CfD Values (NO WELLBORE STORAGE EFFECTS) (1"x1" format)
3
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Cinco-Samaniego" Skin Factor Correlation
"Cinco-Samaniego" Skin Factor Correlation: (used to relate the fractured well case to the Pseudoradial flow skin factor)
4
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Bourdet-Gringarten Type Curve (Unfractured Well)
Bourdet-Gringarten Type Curve: pwD and pwD' vs. tD/CD — Various CD Values (Radial Flow Case — Includes Wellbore Storage and Skin Effects) (1"x1" format)
5
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Economides" Type Curve (CfD =1, CDf =various)
"Economides" Type Curve: pwD and pwD' vs. tDxf/CDf — CfD =1 (Fractured Well Case — Includes Wellbore Storage Effects) (1"x1" format)
6
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Economides" Type Curve (CfD =2, CDf =various)
"Economides" Type Curve: pwD and pwD' vs. tDxf/CDf — CfD =2 (Fractured Well Case — Includes Wellbore Storage Effects) (1"x1" format)
7
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Economides" Type Curve (CfD =2, CDf =various)
"Economides" Type Curve: pwD and pwD' vs. tDxf/CDf — CfD =5 (Fractured Well Case — Includes Wellbore Storage Effects) (1"x1" format)
8
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Economides" Type Curve (CfD =10, CDf =various)
"Economides" Type Curve: pwD and pwD' vs. tDxf/CDf — CfD =10 (Fractured Well Case — Includes Wellbore Storage Effects) (1"x1" format)
9
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) "Economides" Type Curve (CfD =1x10-3, CDf =various)
"Economides" Type Curve: pwD and pwD' vs. tDxf/CDf — CfD =1x10-3 (Fractured Well Case — Includes Wellbore Storage Effects) (1"x1" format)
10
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Ansah Type Curve — Pressure Buildup in a Bounded (Closed) Reservoir System
Ansah Type Curve: Pressure Buildup in a Bounded (Closed) Reservoir System (1"x1" format)
11
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Stewart Type Curve — Well in an Infinite-Acting Reservoir System with a Single or Multiple Sealing Faults
Stewart Type Curve: Well in an Infinite-Acting Reservoir System with a Single or Multiple Sealing Faults. (1"x1" format)
12
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054)
Type Curves for Naturally Fractured Reservoir Systems (1"x1" Format) (No Wellbore Storage or Skin Effects)
"Stewart and Ascharsobbi" Type Curve: pwD' vs. tDλ/4 — Various λ and ω Values
"Onur, Satman, and Reynolds" Type Curve: pwD' vs. tDλ/4 — Various λ and ω Values
13
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-1, ω=1x10-1).
14
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-2, ω=1x10-1).
15
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-3, ω=1x10-1).
16
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-4, ω=1x10-1).
17
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-1, ω=1x10-2).
18
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-2, ω=1x10-2).
19
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-3, ω=1x10-2).
20
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Angel Type Curve — Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects
Angel Type Curve: Type Curves for Naturally Fractured Reservoir Systems — with Wellbore Storage and Skin Effects (1"x1" format) (αD=λCD=1x10-4, ω=1x10-2).
21
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Well Mach-3X (SPE 13054)
Field Case: Well Mach-3X (SPE 13054)
These data were obtained from a field in Western Venezuela and in this case the analysts claim that the well performance indicates pseudosteady-state interporosity flow character. You are to verify (or disprove) this conjecture using both the drawdown and buildup test data. As noted earlier, these drawdown and buildup tests were not performed at the same relative time in the life of the well.
Using the attached plots, you are to perform "type curve" analysis on these data and provide estimates of the following parameters (as appropriate):
a. The formation permeability, k. c. The dimensionless wellbore storage coefficient, CD. e. The near-well skin factor (compare to semilog analysis), s. f. The dimensionless fracture storativity ratio, ω.* g. The dimensionless interporosity flow coefficient, λ.*
* Assuming that naturally fractured reservoir behavior is exhibited.
Note:
You are also to verify/calculate properties using the specialized plots that are provided (pressure versus shut-in time and pressure versus logarithm of shut-in time, effective shut-in time, and Horner time—as well as the Muskat-Arps plot (pressure versus pressure derivative) for the analysis of late-time pressure buildup data). Be sure to perform all Cartesian and semilog analyses (which are relevant) and provide all results and calculations.
22
Naturally Fractured Reservoirs (DaPrat, et al, paper SPE 13054) Well Mach-3X (SPE 13054) — Pressure Drawdown Test Sequence
Field Case: Well Mach-3X (SPE 13054) — Pressure Drawdown Test Sequence