ASTM D4630-96(2008)
(Test Method)Standard Test Method for Determining Transmissivity and Storage Coefficient of Low-Permeability Rocks by In Situ Measurements Using the Constant Head Injection Test (Withdrawn 2017)
Standard Test Method for Determining Transmissivity and Storage Coefficient of Low-Permeability Rocks by In Situ Measurements Using the Constant Head Injection Test (Withdrawn 2017)
SIGNIFICANCE AND USE
Test Method—The constant pressure injection test method is used to determine the transmissivity and storativity of low-permeability formations surrounding packed-off intervals. Advantages of the method are: (1) it avoids the effect of well-bore storage, (2) it may be employed over a wide range of rock mass permeabilities, and (3) it is considerably shorter in duration than the conventional pump and slug tests used in more permeable rocks.
Analysis—The transient water flow rate data obtained using the suggested test method are evaluated by the curve-matching technique described by Jacob and Lohman (1) and extended to analysis of single fractures by Doe et al. (2). If the water flow rate attains steady state, it may be used to calculate the transmissivity of the test interval (3).
Units:
Conversions—The permeability of a formation is often expressed in terms of the unit darcy. A porous medium has a permeability of 1 darcy when a fluid of viscosity 1 cp (1 mPa·s) flows through it at a rate of 1 cm3/s (10−6 m3/s)/1 cm2 (10−4 m2) cross-sectional area at a pressure differential of 1 atm (101.4 kPa)/1 cm (10 mm) of length. One darcy corresponds to 0.987 μm2. For water as the flowing fluid at 20°C, a hydraulic conductivity of 9.66 μm/s corresponds to a permeability of 1 darcy.
SCOPE
1.1 This test method covers a field procedure for determining the transmissivity and storativity of geological formations having permeabilities lower than 10−3 μm2 (1 millidarcy) using constant head injection.
1.2 The transmissivity and storativity values determined by this test method provide a good approximation of the capacity of the zone of interest to transmit water, if the test intervals are representative of the entire zone and the surrounding rock is fully water-saturated.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
WITHDRAWN RATIONALE
This test method covers a field procedure for determining the transmissivity and storativity of geological formations having permeabilities lower than 10−3 μm2 (1 millidarcy) using constant head injection.
Formerly under the jurisdiction of Committee D18 on Soil and Rock, this test method was withdrawn in March 2017 in accordance with section 10.6.3 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.
General Information
Relations
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D4630 − 96 (Reapproved 2008)
Standard Test Method for
Determining Transmissivity and Storage Coefficient of Low-
Permeability Rocks by In Situ Measurements Using the
Constant Head Injection Test
This standard is issued under the fixed designation D4630; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
µ = fluid viscosity, and
g = acceleration due to gravity.
1.1 This test method covers a field procedure for determin-
ing the transmissivity and storativity of geological formations
2.1.2 storage coeffıcient, S—the storage coefficient of a
−3 2
havingpermeabilitieslowerthan10 µm (1millidarcy)using
formation of thickness, b, is defined as follows:
constant head injection.
S 5 S ·b (3)
s
1.2 The transmissivity and storativity values determined by
where:
this test method provide a good approximation of the capacity
S = specific storage.
s
of the zone of interest to transmit water, if the test intervals are
The ebrss is the specific storage of a material if it were
representative of the entire zone and the surrounding rock is
fully water-saturated. homogeneous and porous over the entire interval. The specific
storage is given as follows:
1.3 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this S 5 ρg ~C 1nC ! (4)
s b w
standard.
where:
1.4 This standard does not purport to address all of the
C = bulk rock compressibility,
b
safety concerns, if any, associated with its use. It is the
C = fluid compressibility, and
w
responsibility of the user of this standard to establish appro-
n = formation porosity.
priate safety and health practices and determine the applica-
2.2 Symbols:
bility of regulatory limitations prior to use.
−1 2
2.2.1 C —bulk rock compressibility (M LT ).
b
−1 2
2. Terminology
2.2.2 C —compressibility of water (M LT ).
w
2.1 Definitions of Terms Specific to This Standard: 2.2.3 G—dimensionless function.
2.1.1 transmissivity, T—the transmissivity of a formation of −1
2.2.4 K—hydraulic conductivity (LT ).
thickness, b, is defined as follows:
2.2.4.1 Discussion—The use of symbol K for the term
T 5 K·b (1) hydraulic conductivity is the predominant usage in groundwa-
ter literature by hydrogeologists, whereas the symbol k is
where:
commonly used for this term in the rock and soil mechanics
K = hydraulic conductivity.
and soil science literature.
The hydraulic conductivity, K, is related to the permeability, −1 −2
2.2.5 P—excess test hole pressure (ML T ).
k , as follows:
3 −1
2.2.6 Q—excess water flow rate (L T ).
K 5 kρg/µ (2)
3 −1
2.2.7 Q —maximum excess water flow rate (L T ).
o
where:
2.2.8 S—storativity (or storage coefficient) (dimensionless).
ρ = fluid density,
−1
2.2.9 S —specific storage (L ).
s
2 −1
2.2.10 T—transmissivity (L T ).
ThistestmethodisunderthejurisdictionofASTMCommitteeD18onSoiland
2.2.11 b—formation thickness (L).
Rock and is the direct responsibility of Subcommittee D18.21 on Groundwater and
2.2.12 e—fracture aperture (L).
Vadose Zone Investigations.
−2
Current edition approved Sept. 15, 2008. Published October 2008. Originally
2.2.13 g—acceleration due to gravity (LT ).
approved in 1986. Last previous edition approved in 2002 as D4630–96 (2002).
DOI: 10.1520/D4630-96R08. 2.2.14 k—permeability (L ).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4630 − 96 (2008)
2.2.15 n—porosity (dimensionless).
2.2.16 r —radius of test hole (L).
w
2.2.17 t—time elapsed from start of test (T).
2.2.18 α—dimensionless parameter.
−1 −1
2.2.19 µ—viscosity of water (ML T ).
−3
2.2.20 ρ—density of water (ML ).
3. Summary of Test Method
3.1 Aboreholeisfirstdrilledintotherockmass,intersecting
the geological formations for which the transmissivity and
storativity are desired. The borehole is cored through potential
zonesofinterest,andislatersubjectedtogeophysicalborehole
logging over these intervals. During the test, each interval of
interest is packed off at top and bottom with inflatable rubber
packers attached to high-pressure steel tubing.
3.2 The test itself involves rapidly applying a constant
pressure to the water in the packed-off interval and tubing
string, and recording the resulting changes in water flow rate.
The water flow rate is measured by one of a series of flow
meters of different sensitivities located at the surface. The
initial transient water flow rate is dependent on the transmis-
sivity and storativity of the rock surrounding the test interval
andonthevolumeofwatercontainedinthepacked-offinterval
and tubing string.
4. Significance and Use
4.1 Test Method—The constant pressure injection test
method is used to determine the transmissivity and storativity
of low-permeability formations surrounding packed-off inter-
FIG. 1 Equipment Schematic
vals. Advantages of the method are: (1) it avoids the effect of
well-borestorage,(2)itmaybeemployedoverawiderangeof
rock mass permeabilities, and (3) it is considerably shorter in
5.1 Source of Constant Pressure—A pump or pressure
duration than the conventional pump and slug tests used in
intensifier shall be capable of providing an additional amount
more permeable rocks.
of water to the water-filled tubing string and packed-off test
interval to produce a constant pressure of up to 1 MPa in
4.2 Analysis—The transient water flow rate data obtained
magnitude, preferably with a rise time of less than 1% of one
using the suggested test method are evaluated by the curve-
half of the flow rate decay (Q/Q =0.5).
o
matching technique described by Jacob and Lohman (1) and
extended to analysis of single fractures by Doe et al. (2). If the
5.2 Packers—Hydraulically actuated packers are recom-
water flow rate attains steady state, it may be used to calculate
mended because they produce a positive seal on the borehole
the transmissivity of the test interval (3).
wall and because of the low compressibility of water they are
alsocomparativelyrigid.Eachpackershallsealaportionofthe
4.3 Units:
borehole wall at least 0.5 m in length, with an applied pressure
4.3.1 Conversions—The permeability of a formation is of-
at least equal to the excess constant pressure to be applied to
ten expressed in terms of the unit darcy.Aporous medium has
the packed-off interval and less than the formation fracture
a permeability of 1 darcy when a fluid of viscosity 1 cp (1
3 3 2
pressure at that depth.
mPa·s) flows through it at a rate of 1 cm /s (10−6 m /s)/1 cm
(10−4 m ) cross-sectional area at a pressure differential of 1
5.3 Pressure Transducers—The pressure shall be measured
atm (101.4 kPa)/1 cm (10 mm) of length. One darcy corre-
as a function of time, with the transducer located in the
sponds to 0.987 µm . For water as the flowing fluid at 20°C, a
packed-off test interval. The pressure transducer shall have an
hydraulic conductivity of 9.66 µm/s corresponds to a perme-
accuracyofatleast 63kPa,includingerrorsintroducedbythe
ability of 1 darcy.
recording system, and a resolution of at least 1 kPa.
5.4 Flow Meters—Suitable flow meters shall be provided
5. Apparatus
3 3
for measuring water flow rates in the range from 10 cm /s to
NOTE 1—A schematic of the test equipment is shown in Fig. 1.
−3 3
10 cm /s.Commerciallyavailableflowmetersarecapableof
2 3
measuring flow rates as low as 10 cm /s with an accuracy of
−5 3
61% and with a resolution of 10 cm /s; these can test
Theboldfacenumbersinparenthesesrefertothelistofreferencesattheendof
−3
this standard. permeabilities to 10 md based on a 10-m packer spacing.
D4630 − 96 (2008)
Positive displacement flow meters of either the tank type 6.3.1 Quality—Water used for pressure pulse tests shall be
(Haimson and Doe (4) or bubble-type (Wilson, et al (3) are clean, and compatible with the formation. Even small amounts
−3 3
capableofmeasuringflowratesaslowas10 cm /s;thesecan of dispersed solids in the injection water could plug the rock
−4
testpermeabilitiesto10 mdbasedona10-mpackerspacing. face of the test interval and result in a measured transmissivity
value that is erroneously low.
5.5 Hydraulic Systems—The inflatable rubber packers shall
6.3.2 Temperature—The lower limit of the test water tem-
be attached to high-pressure steel tubing reaching to the
perature shall be 5°C below that of the rock mass to be tested.
surface. The packers themselves shall be inflated with water
Cold water injected into a warm rock mass causes air to come
using a separate hydraulic system. The pump or pressure
out of solution, and the resulting bubbles will radically modify
intensifier providing the constant pressure shall be attached to
the pressure transient characteristics.
thesteeltubingatthesurface.Aremotelycontrolleddown-hole
valve, located in the steel tubing immediately above the upper
6.4 Testing:
packer, shall be used for shutting in the test interval and for
6.4.1 Filling and Purging System—Once the packers have
instantaneous starting of tests.
been set, slowly fill the tubing string and packed-off interval
with water to ensure that no air bubbles will be trapped in the
6. Procedure
testintervalandtubing.Closethedownholevalvetoshutinthe
6.1 Drilling Test Holes: testinterval,andallowthetestsectionpressures(asdetermined
6.1.1 Number and Orientation—The number of test holes from downhole pressure transducer reading) to dissipate.
shall be sufficient to supply the detail required by the scope of
6.4.2 Constant Pressure Test—Pressurize the tubing, typi-
the project. The test holes shall be directed to intersect major
cally to between 300 and 600 kPa above the shut-in pressure.
fracture sets, preferably at right angles.
This range of pressures is in most cases sufficiently low to
6.1.2 Test Hole Quality—The drilling procedure shall pro-
minimizedistortionoffracturesadjacentatthetesthole,butin
vide a borehole sufficiently smooth for packer seating, shall
no case should the pressure exceed the minimum principal
contain no rapid changes in direction, and shall minimize
ground stress. It is necessary to provide sufficient volume of
formation damage.
pressurized water to maintain constant pressure during testing.
6.1.3 Test Holes Cored—Core the test holes through zones Open the downhole valve, maintain the constant pressure, and
of potential interest to provide information for locating test
record the water flow rate as a function of time.Then close the
intervals. downhole valve and repeat the test for a higher value of
6.1.4 Core Description—Describe the rock core from the
constant test pressure. A typical record is shown in Fig. 2.
testholeswithparticularemphasisonthelithologyandnatural
discontinuities.
7. Calculation and Interpretation of Test Data
6.1.5 Geophysical Borehole Logging—Log geophysically
7.1 The solution of the differential equation for unsteady
the zones of potential interest. In particular, run electrical-
state flow from a borehole under constant pressure located in
inductionandgamma-gammadensitylogs.Wheneverpossible,
an extensive aquifer is given by Jacob and Lohman (1) as:
also use sonic logs and the acoustic televiewer. Run other logs
Q 5 2πTP G~α!/ρg, (5)
as required.
6.1.6 Washing Test Holes—The test holes must not contain
where:
any material that could be washed into the permeable zones
Q = water flow rate,
during testing, thereby changing the transmissivity and stor-
T = transmissivity of the test interval,
ativity. Flush the test holes with clean water until the return is
P = excess test hole pressure,
free from cuttings and other dispersed solids.
ρ = water density,
g = acceleration due to gravity, and
6.2 Test Intervals:
G(α) = function of the dimensionless parameter α:
6.2.1 Selection of Test Intervals—Determine test intervals
from the core descriptions, geophysical borehole logs, and, if
α 5 Tt/Sr (6)
w
necessary, from visual inspection of the borehole with a
where:
borescope or TV camera.
t = time elapsed from start of test,
6.2.2 Changes in Lithology—Test each major change in
S = storativity, and
lithology that can be isolated between packers.
r = radius of the borehole over the test interval.
w
6.2.3 Sampling Discontinuities—Discontinuities are often
NOTE 2—For bounded aquifers, the reader is referred to Hantush (5).
the major permeable features in hard rock. Test jointed zones,
7.1.1 In Fig. 2, the flow rate in the shut-in, packed-off
fault zones, bedding planes, and the like, both by isolating
interval is considered constant. In those cases where the
individual features and by evaluating the combined effects of
response of the shut-in interval is time dependent, interpreta-
several features.
tion of the constant pressure test is unaffected, provided the
6.2.4 Redundancy of Tests—To evaluate variability in trans-
time dependency is linear.
missivity and storativity, conduct three or more tests in each
rocktype,ifhomogeneous.Iftherockisnothomogeneous,the
7.2 To determine the transmissivity, T, and storativity, S,
sets of tests should encompass similar types of discontinuities.
dataonthewaterflowrateatconstantpressureasafunctionof
6.3 Test Water: time are plotted in the following manner (1).
D4630 − 96 (2008)
FIG. 2 Typical Flow Rate Record
7.2.1 First, plot a type curve log of of the function G(α) 8.1.1 Introduction—The introductory section is intended to
versus α where values of G(α) are given in Table 1.
present the scope and purpose of the constant pressure test
7.2.2 Second, on transparent logarithmic paper to the same
program, and the characteristics of rock mass tested.
scale,plotvaluesofthelogofflowrate, Q,versusvaluesofthe
8.1.1.1 Scope of Testing Program:
log of time, t at the same scale as the type curve.
(1)Reportthelocationandorientationoftheboreholesand
7.2.3 Then, by placing the experimental data over the
test intervals. For tests in many boreholes or in a variety of
theoretical curve, the best fit of the data to the curve can be
rock types, present the matrix in tabular form.
made.
(2)Rationale for test location selection, including the
7.2.4 Determine the values of transmissivity, T, and
reasons for the number, location, and size of test intervals.
storativity, S, using Eq 5 and Eq 6 from the coordinates of any
(3)Discuss in general terms limitations of the testing
point in both coordinate systems.
program, stating the areas of interest which are not covered by
8. Report the testing program and the limitations of the data within the
areas of application.
8.1 The report shall include the following:
−4 12 A
TABLE 1 Value
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.