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ASTM D5923-96(2010)

(Guide)

Standard Guide for Selection of Kriging Methods in Geostatistical Site Investigations

Standard Guide for Selection of Kriging Methods in Geostatistical Site Investigations

SIGNIFICANCE AND USE
This guide is intended to encourage consistency and thoroughness in the application of kriging methods to environmental, geotechnical, and hydrogeological site investigations.
This guide may be used to assist those performing a kriging study or as an explanation of procedures for qualified nonparticipants that may be reviewing or auditing the study.
This guide encourages the use of site-specific information for the selection of an appropriate kriging method; however, the quality of data, the sampling density, and site coverage cannot be improved or compensated by any choice of kriging method.
This guide describes conditions for which kriging or particular kriging methods are recommended. However, these methods are not necessarily inappropriate if the stated conditions are not encountered.
This guide should be used in conjunction with Guides D5549, D5922, and D5924.
SCOPE
1.1 This guide covers recommendations for selecting appropriate kriging methods based on study objectives, exploratory data analysis, and analysis of spatial variation.
1.2 This guide considers commonly used forms of kriging, including ordinary kriging, simple kriging, lognormal kriging, universal kriging, and indicator kriging. Multivariate, space-time, and other less-frequently used kriging methods are not discussed; however, this is not intended to reflect any judgement as to the validity of these methods.
1.3 This guide describes conditions for which kriging methods are not appropriate and for which geostatistical simulations approaches should be used.
1.4 This guide does not discuss non-geostatistical alternatives to kriging, such as splines or inverse-distance techniques.
1.5 This guide does not discuss the basic principles of kriging. Introductions to geostatistics and kriging may be found in numerous texts including Refs (1-3). A review of kriging methods is given in Ref. (4).
1.6 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.
1.7 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.

General Information

Status
Historical
Publication Date
30-Apr-2010
ICS
07.060 - Geology. Meteorology. Hydrology
Technical Committee
D18 - Soil and Rock
Drafting Committee
D18.01 - Surface and Subsurface Investigation
Current Stage
Ref Project

Relations

Replaces
ASTM D5923-96(2004) - Standard Guide for Selection of Kriging Methods in Geostatistical Site Investigations
Effective Date
01-May-2010
Replaced By
ASTM D5923-18 - Standard Guide for Selection of Kriging Methods in Geostatistical Site Investigations
Effective Date
15-Dec-2018
Referred By
ASTM D5922-18 - Standard Guide for Analysis, Interpretation, and Modeling of Spatial Variation in Geostatistical Site Investigations
Effective Date
01-May-2010
Referred By
ASTM D5924-18 - Standard Guide for Selection of Simulation Approaches in Geostatistical Site Investigations
Effective Date
01-May-2010
Referred By
ASTM D8215-21 - Standard Practice for Statistical Modeling of Uncertainty in Assessment of In-place Coal Resources
Effective Date
01-May-2010

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ASTM D5923-96(2010) - Standard Guide for Selection of Kriging Methods in Geostatistical Site InvestigationsASTM D5923-96(2010) - Standard Guide for Selection of Kriging Methods in Geostatistical Site Investigations
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ASTM D5923-96(2010) - Standard Guide for Selection of Kriging Methods in Geostatistical Site Investigations
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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: D5923 − 96 (Reapproved 2010)
Standard Guide for
Selection of Kriging Methods in Geostatistical Site
Investigations
This standard is issued under the fixed designation D5923; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
Geostatistics is a framework for data analysis, estimation, and simulation in media whose
measurable attributes show erratic spatial variability yet also possess a degree of spatial continuity
imparted by the natural and anthropogenic processes operating therein. The soil, rock, and contained
fluids encountered in environmental or geotechnical site investigations present such features, and their
sampled attributes are therefore amenable to geostatistical treatment. Kriging methods are geostatis-
tical techniques for spatial estimation belonging to the class of least-squares estimators. This guide
reviews criteria for selecting a kriging method, offering direction based on a consensus of views
without recommending a standard practice to follow in all cases.
1. Scope priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
1.1 This guide covers recommendations for selecting appro-
1.7 This guide offers an organized collection of information
priate kriging methods based on study objectives, exploratory
or a series of options and does not recommend a specific
data analysis, and analysis of spatial variation.
course of action. This document cannot replace education or
1.2 This guide considers commonly used forms of kriging,
experienceandshouldbeusedinconjunctionwithprofessional
including ordinary kriging, simple kriging, lognormal kriging,
judgment. Not all aspects of this guide may be applicable in all
universal kriging, and indicator kriging. Multivariate, space-
circumstances. This ASTM standard is not intended to repre-
time, and other less-frequently used kriging methods are not
sent or replace the standard of care by which the adequacy of
discussed; however, this is not intended to reflect any judge-
a given professional service must be judged, nor should this
ment as to the validity of these methods.
document be applied without consideration of a project’s many
1.3 This guide describes conditions for which kriging meth- unique aspects. The word “Standard” in the title of this
document means only that the document has been approved
odsarenotappropriateandforwhichgeostatisticalsimulations
approaches should be used. through the ASTM consensus process.
1.4 This guide does not discuss non-geostatistical alterna-
2. Referenced Documents
tives to kriging, such as splines or inverse-distance techniques.
2.1 ASTM Standards:
1.5 This guide does not discuss the basic principles of
D653 Terminology Relating to Soil, Rock, and Contained
kriging. Introductions to geostatistics and kriging may be
Fluids
found in numerous texts including Refs (1-3). A review of
D5549 Guide for The Contents of Geostatistical Site Inves-
kriging methods is given in Ref. (4).
tigation Report (Withdrawn 2002)
1.6 This standard does not purport to address all of the
D5922 Guide for Analysis of Spatial Variation in Geostatis-
safety concerns, if any, associated with its use. It is the
tical Site Investigations
responsibility of the user of this standard to establish appro-
D5924 Guide for Selection of Simulation Approaches in
Geostatistical Site Investigations
This guide is under the jurisdiction ofASTM Committee D18 on Soil and Rock
and is the direct responsibility of Subcommittee D18.01 on Surface and Subsurface
Characterization. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2010. Published September 2010. Originally contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
approved in 1996. Last previous edition approved in 2004 as D5923 – 96 (2004). Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/D5923-96R10. the ASTM website.
2 4
The boldface numbers in parentheses refer to a list of references at the end of The last approved version of this historical standard is referenced on
the text. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5923 − 96 (2010)
3. Terminology 3.1.17 simple kriging, n—a form of kriging for which the
meanoftheestimatedvariableisaknownconstantandthesum
3.1 Definitions of Terms Specific to This Standard:
of sample weights is unconstrained.
3.1.1 additivity, n—a mathematical property of a regional-
3.1.18 simulation, n—in geostatistics, a Monte-Carlo proce-
izedvariablestatingthatitcanbecombinedlinearlyinorderto
dure for generating realizations of fields based on the random
define a similar variable on a larger support.
function model chosen to represent a regionalized variable. In
3.1.2 block kriging, n—a form of kriging in which the
addition to honoring a random function model, the realizations
variable to be estimated has a rectangular or possibly irregular
may also be constrained to honor data values observed at
one-, two-, or three-dimensional support.
sampled locations.
3.1.3 drift, n—in geostatistics, a systematic spatial variation
3.1.19 smoothing effect, n—in geostatistics, the reduction in
of the local mean of a variable, usually expressed as a
spatial variance of estimated values compared to true values.
polynomial function of location coordinates.
3.1.20 spatial average, n—a quantity obtained by averaging
3.1.4 estimation, n—a procedure by which the value of a
a regionalized variable over a finite region of space.
variableatanunsampledlocationispredictedusingaweighted
3.1.21 support, n—in geostatistics, the spatial averaging
average of sample values from the neighborhood of that
region over which a regionalized variable is defined, often
location.
approximated by a point for sample-scale variables.
3.1.5 field, n—in geostatistics, the region of one-, two- or
3.1.22 universal kriging, n—a form of kriging in which
three-dimensional space within which a regionalized variable
additional weighting constraints are introduced in order to
is defined.
account for a drift in the estimated variable.
3.1.6 indicator kriging, n—a form of kriging in which all
3.1.23 variogram, n—a measure of spatial variation defined
data are indicator variables.
asonehalfthevarianceofthedifferencebetweentwovariables
and expressed as a function of the lag; it is also sometimes
3.1.7 indicator variable, n—a regionalized variable that can
referred to as the semi-variogram.
have only two possible values, 0 or 1.
3.2 For definitions of other terms used in this guide, refer to
3.1.8 kriging, n—an estimation method where sample
Terminology D653 and Guides D5549, D5922, and D5924.A
weights are obtained using a linear least-squares optimization
complete glossary of geostatistical terminology is given in Ref
procedure based on a mathematical model of spatial variability
(7).
and where the unknown variable and the available sample
values may have a point or block support.
4. Significance and Use
3.1.9 kriging variance, n—theexpectedvalueofthesquared
4.1 This guide is intended to encourage consistency and
difference between the true value of an unknown variable and
thoroughness in the application of kriging methods to
its kriging estimate, sometimes used as a measure of kriging
environmental, geotechnical, and hydrogeological site investi-
precision.
gations.
3.1.10 lognormal kriging, n—thekrigingoflog-transformed
4.2 This guide may be used to assist those performing a
variables followed by a back-transformation procedure based
kriging study or as an explanation of procedures for qualified
on a lognormal distribution model.
nonparticipants that may be reviewing or auditing the study.
3.1.11 nugget effect, n—the component of spatial variance
4.3 This guide encourages the use of site-specific informa-
unresolved by the sample spacing, including the variance due
tion for the selection of an appropriate kriging method;
to measurement error.
however, the quality of data, the sampling density, and site
3.1.12 ordinary kriging, n—a form of kriging for which the
coverage cannot be improved or compensated by any choice of
mean of the estimated variable is an unknown constant and the
kriging method.
sample weights sum to one.
4.4 This guide describes conditions for which kriging or
3.1.13 point, n—in geostatistics, the location in the field at
particular kriging methods are recommended. However, these
which a regionalized variable is defined. It also commonly
methods are not necessarily inappropriate if the stated condi-
refers to the support of sample-scale variables.
tions are not encountered.
3.1.14 point kriging, n—a form of kriging in which the
4.5 This guide should be used in conjunction with Guides
variable to be estimated has the
...

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5.1 Assumptions of Solution:  
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Note 7: Short term refers to the duration of the slug test.
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5.1 Assumptions:  
5.1.1 The control well discharges at a constant rate, Q.  
5.1.2 The control well, observation wells, and piezometers are of infinitesimal diameter.  
5.1.3 The unconfined aquifer is homogeneous and really extensive.  
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5.1.5 The geometry of the aquifer, control well, observation wells, and piezometers is shown in Fig. 2. The geometry of the test wells should be adjusted depending on the parameters of interest.
FIG. 2 Cross Section Through a Discharging Well Screened in Part of an Unconfined Aquifer  
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5.2.1 Use of the Neuman (1) method assumes the control well is of infinitesimal diameter. The storage in the control well may adversely affect drawdown measurements obtained in the early part of the test. See 5.2.2 of Practice D4106 for assistance in determining the duration of the effects of well-bore storage on drawdown.  
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1.4 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard. Reporting of test result in units other than SI shall not be regarded as nonconformance with this standard.  
1.5 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.5.1 The procedures used to specify how data are collected/recorded or calculated in the standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering data.  
1.6 This practice offers a set of in...

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ASTM
ASTM D6391-11(2020)(Test Method)
Standard Test Method for Field Measurement of Hydraulic Conductivity Using Borehole Infiltration

SIGNIFICANCE AND USE
5.1 This test method provides a means to measure the hydraulic conductivity of isotropic materials and the maximum vertical and minimum horizontal hydraulic conductivities of anisotropic materials, especially in the low ranges associated with fine-grained clayey soils, 1×10–7 m/s to 1×10–11 m/s.  
5.2 This test method is useful for measuring liquid flow through soil hydraulic barriers, such as compacted clay barriers used at waste containment facilities, for canal and reservoir liners, for seepage blankets, and for amended soil liners, such as those used for retention ponds or storage tanks. Due to the boundary condition assumptions used in deriving the equations for the limiting hydraulic conductivities, the thickness of the unit tested must be at least 600 mm. This requirement is increased to 800 mm if the material being tested is underlain by a material that is far less permeable.  
5.3 The soil layer being tested must have sufficient cohesion to stand open during excavation of the borehole.  
5.4 This test method provides a means to measure infiltration rate into a moderately large volume of soil. Tests on large volumes of soil can be more representative than tests on small volumes of soil. Multiple installations properly spaced provide a greater volume and an indication of spatial variability.  
5.5 The data obtained from this test method are most useful when the soil layer being tested has a uniform distribution of hydraulic conductivity and of pore space and when the upper and lower boundary conditions of the soil layer are well defined.  
5.6 Changes in water temperature can introduce errors in the flow measurements. Temperature changes cause fluctuations in the water levels that are not related to flow. This problem is most pronounced when a small diameter standpipe or Marriotte bottle is used in soils having hydraulic conductivities of 5×10–10 m/s or less.  
5.7 The effects of temperature changes and other environmental perturbations are taken into a...
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1.1 This test method covers field measurement of hydraulic conductivity (also referred to as coefficient of permeability) of porous materials using a cased borehole technique. When isotropic conditions can be assumed and a flush borehole is employed, the method yields the hydraulic conductivity of the porous material. When isotropic conditions cannot be assumed, the method yields limiting values of the hydraulic conductivity in the vertical direction (upper limit) if a single stage is conducted and the horizontal direction (lower limit) if a second stage is conducted. For anisotropic conditions, determination of the actual hydraulic conductivity requires further analysis by qualified personnel.  
1.2 This test method may be used for compacted fills or natural deposits, above or below the water table, that have a mean hydraulic conductivity less than or equal to 1×10–5 m/s (1×10–3 cm/s).  
1.3 Hydraulic conductivity greater than 1×10–5 m/s may be determined by ordinary borehole tests, for example, U.S. Bureau of Reclamation 7310 (1)2; however, the resulting value is an apparent conductivity.  
1.4 For this test method, a distinction must be made between “saturated” (Ks) and “field-saturated” (Kfs) hydraulic conductivity. True saturated conditions seldom occur in the vadose zone except where impermeable layers result in the presence of perched water tables. During infiltration events or in the event of a leak from a lined pond, a “field-saturated” condition develops. True saturation does not occur due to entrapped air (2). The entrapped air prevents water from moving in air-filled pores, which may reduce the hydraulic conductivity measured in the field by as much as a factor of two compared with conditions when trapped air is not present (3). This test method develops the “field-saturated” condition.  
1.5 Experience with this test method has been predominantly in materials having a degree of saturation of 70 % or more...

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ASTM D6432-19(Guide)
Standard Guide for Using the Surface Ground Penetrating Radar Method for Subsurface Investigation

SIGNIFICANCE AND USE
5.1 Concepts—This guide summarizes the equipment, field procedures, and data processing methods used to interpret geologic conditions, and to identify and provide locations of geologic anomalies and man-made objects with the GPR method. The GPR uses high-frequency EM waves (from 10 to 3000 MHz) to acquire subsurface information. Energy is propagated downward into the ground from a transmitting antenna and is reflected back to a receiving antenna from subsurface boundaries between media possessing different EM properties. The reflected signals are recorded to produce a scan or trace of radar data. Typically, scans obtained as the antenna(s) are moved over the ground surface are placed side by side to produce a radar profile.  
5.1.1 The vertical scale of the radar profile is in units of two-way travel time, the time it takes for an EM wave to travel down to a reflector and back to the surface. The travel time may be converted to depth by relating it to on-site measurements or assumptions about the velocity of the radar waves in the subsurface materials.  
5.1.2 Vertical variations in propagation velocity due to changing EM properties of the subsurface can make it difficult to apply a linear time scale to the radar profile (Ulriksen (31)).  
5.2 Parameter Being Measured and Representative Values:  
5.2.1 Two-Way Travel Time and Velocity—A GPR trace is the record of the amplitude of EM energy that has been reflected from interfaces between materials possessing different EM properties and recorded as a function of two-way travel time. To convert two-way times to depths, it is necessary to estimate or determine the propagation velocity of the EM pulses or waves. The relative permittivity of the material (εr) through which the EM pulse or wave propagates mostly determines the propagation velocity of the EM wave. The propagation velocity through the material is approximated using the following relationship (see full formula in Balanis (32)):
    where:
  c  ...
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1.1 Purpose and Application:  
1.1.1 This guide covers the equipment, field procedures, and interpretation methods for the assessment of subsurface materials using the Ground Penetrating Radar (GPR) Method. GPR is most often employed as a technique that uses high-frequency electromagnetic (EM) waves (from 10 to 7000 MHz) to acquire subsurface information. GPR detects changes in EM properties (dielectric permittivity, conductivity, and magnetic permeability), that in a geologic setting, are a function of soil and rock material, water content, and bulk density. Data are normally acquired using antennas placed on the ground surface or in boreholes. The transmitting antenna radiates EM waves that propagate in the subsurface and reflect from boundaries at which there are EM property contrasts. The receiving GPR antenna records the reflected waves over a selectable time range. The depths to the reflecting interfaces are calculated from the arrival times in the GPR data if the EM propagation velocity in the subsurface can be estimated or measured.  
1.1.2 GPR measurements as described in this guide are used in geologic, engineering, hydrologic, and environmental applications. The GPR method is used to map geologic conditions that include depth to bedrock, depth to the water table (Wright et al (1)2), depth and thickness of soil strata on land and under fresh water bodies (Beres and Haeni (2)), and the location of subsurface cavities and fractures in bedrock (Ulriksen (3) and Imse and Levine (4)). Other applications include the location of objects such as pipes, drums, tanks, cables, and boulders, mapping landfill and trench boundaries (Benson et al (5)), mapping contaminants (Cosgrave et al (6); Brewster and Annan (7); Daniels et al (8)), conducting archaeological (Vaughan (9)) and forensic investigations (Davenport et al (10)), inspection of brick, masonry, and concrete structures, roads and railroad trackbed studies (Ulrik...

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ASTM
ASTM D5878-19(Guide)
Standard Guides for Using Rock-Mass Classification Systems for Engineering Purposes

SIGNIFICANCE AND USE
4.1 The classification systems included in this standard and their respective applications are as follows:  
4.1.1 Rock Mass Rating System (RMR) or Geomechanics Classification—This system has been applied to tunneling, hard-rock mining, coal mining, stability of rock slopes, rock foundations, borability, rippability, dredgability, weatherability, and rock bolting.  
4.1.2 Rock Structure Rating System (RSR)—This system has been used in tunnel support and excavation and in other ground support work in mining and construction.  
4.1.3 The Q System or Norwegian Geotechnical Institute System (NGI)—This system has been applied to work on tunnels and chambers, rippability, excavatability, hydraulic erodibility, and seismic stability of roof-rock.  
4.1.4 The Unified Rock Classification System (URCS)—This system has been applied to work on foundations, methods of excavation, slope stability, uses of earth materials, blasting characteristics of earth materials, and transmission of groundwater.  
4.1.5 The Rock Material Field Classification System (RMFCS)—This system has been used mainly for applications involving shallow excavation, particularly with regard to hydraulic erodibility in earth spillways, excavatability, construction quality of rock, fluid transmission, and rock-mass stability (2).  
4.1.6 The New Austrian Tunneling Method (NATM)—This system is used for both conventional (cyclical, such as drill-and-blast) and continuous (tunnel-boring machine or TBM) tunneling. This is a tunneling procedure in which design is extended into the construction phase by continued monitoring of rock displacement. Support requirements are revised to achieve stability (3).
Note 2: The Austrian standard (4) specifies methods of payment based on coding of excavation volume and means of support.  
4.1.7 The Coal Mine Roof Rating (CMRR)—This system applies to bedded coal-measure rocks, in particular with regard to their structural competence as influenced by discontinuities in the...
SCOPE
1.1 These guides offer the selection of a suitable system of classification of rock mass for specific engineering purposes, such as tunneling and shaft-sinking, excavation of rock chambers, ground support, modification and stabilization of rock slopes, and preparation of foundations and abutments. These classification systems may also be of use in work on rippability of rock, quality of construction materials, and erosion resistance. Although widely used classification systems are treated in this standard, systems not included here may be more appropriate in some situations, and may be added to subsequent editions of this standard.  
1.2 The valid, effective use of this standard is contingent upon the prior complete definition of the engineering purposes to be served and on the complete and competent definition of the geology and hydrology of the engineering site. Further, the person or persons using this standard shall have had field experience in studying rock-mass behavior. An appropriate reference for geotechnical mapping of large underground openings in rock is provided by Guide D4879.  
1.3 This standard identifies the essential characteristics of seven classification systems. It does not include detailed guidance for application to all engineering purposes for which a particular system might be validly used. Detailed descriptions of the first five systems are presented in STP 984 (1),2 with abundant references to source literature. Details of two other classification systems and a listing of seven Japanese systems are also presented.  
1.4 The range of applications of each of the systems has grown since its inception. This standard summarizes the major fields of application up to this time of each of the seven classification systems.  
1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are mathematical conversions to inch-pounds units that are provided for inf...

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ASTM D3213-19(Practice)
Standard Practices for Handling, Storing, and Preparing Soft Intact Marine Soil

SIGNIFICANCE AND USE
5.1 Disturbance imparted to sediments after sampling can significantly affect some geotechnical properties. Careful practices need to be followed to minimize soil fabric changes caused from handling, transporting, storing, and preparing sediment specimens for testing.
Note 1: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection, etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on may factors; Practice D3740 provides a means of evaluating some of those factors.  
5.2 The practices presented in this document should be used with soil that has a very soft or soft shear strength (undrained shear strength less than 25 kPa (3.6 psi)) consistency.
Note 2: Some soils that are obtained at or just below the seafloor quickly deform under their own weight if left unsupported. This type of behavior presents special problems for some types of testing. Special handling and preparation procedures are required under those circumstances. Tests, such as the handheld vane (D4648/D4648M) or miniature vane (D8121/D8121M), are sometimes performed at sea to minimize the effect of storage time and handling on soil properties. An undrained shear strength of less than 25 kPa was selected based on Terzaghi and Peck.3 They defined a soft saturated clay as having an undrained shear strength less than 25 kPa.  
5.3 These practices shall apply to specimens of naturally formed marine soil (that may or may not be fragile or highly sensitive) that will be used for density determination, consolidation, permeability testing or shear strength testing with or without stress-strain properties and volume change measurements (see Note 3). In addition, dy...
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1.1 These practices cover methods for project/cruise reporting, and handling, transporting and storing soft cohesive intact marine soil. Procedures for preparing soil specimens for triaxial strength, and consolidation testing are also presented.  
1.2 These practices may include the handling and transporting of sediment specimens contaminated with hazardous materials and samples subject to quarantine regulations.  
1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information only and are not considered standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.  
1.4 These practices offer a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of these practices may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project’s many unique aspects. The word “Standard” in the title means only that the document has been approved through the ASTM consensus process.  
1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Sections 1, 2 and 7.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendat...

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ASTM
ASTM D4630-19(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

SIGNIFICANCE AND USE
5.1 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.  
5.2 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)4 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).  
Note 2: The quality of the result produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors.
Note 3: The function of wells in any unconfined setting in a fractured terrain might make the determination of k problematic because the wells might only intersect tributary or subsidiary channels or conduits. The problems determining the k of a channel or conduit notwithstanding, the partial penetration of tributary channels may make determination of a meaningful number difficult. If plots of k in carbonates and other fractured settings are made and compared, they may show no indication that there are conduits or channels present, except when with the lowest probability one maybe intersected by a borehole and can be verified, such pr...
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 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. Reporting of test results in units other than SI shall not be regarded as nonconformance with this standard.  
Note 1: Unit Conversions—The permeability of a formation is often expressed in terms of the unit darcy (non-SI). 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. Permeabilities may also be expressed as millidarcy (md), which is not an SI unit.  
1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026.  
1.4.1 The procedures used to specify how data are collected/recorded or calculated, in this standard are regarded as the industry standard. In addition, they are representative of the significant digits that generally should be retained. The procedures used do not consider material variation, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of repor...

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