ASTM D7099-04

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D7099–04
Standard Terminology Relating to
Frozen Soil and Rock
This standard is issued under the fixed designation D7099; 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 lated Ground-Ice Terms, National Snow and Ice Data
Center/World Data Center for Glaciology, Boulder, Colo-
1.1 This terminology includes all of those terms which
rado
relate to frozen soils and rocks.
National Snow and Ice Data Center, 2003, English Lan-
1.2 It is based on: a list of definitions drawn up by ASTM
guage Glossary of Permafrost and Related Ground-Ice
Sub-Committee D18.19 (ASTM Z6948 Z, WK 3613); ASTM
Terms, Boulder, Colorado, http://nsdic.org/fgdc/glossary/
Standards; a list of definitions drawn up by the Canadian
english.html
Geomorphology Research Group (CGRG); the Glossary of
Natural Resources Conservation Service, United States De-
Permafrost and Related Ground-Ice Terms developed by the
partment of Agriculture, Keys to Soil Taxonomy, Ninth
NationalSnowandIceDataCenter(NSIDC),attheUniversity
Edition, 2003, 331 pp., http://soils.usda.gov/technical/
of Colorado, at Boulder; the Keys to Soil Taxonomy of the
classication/tax_keys
United States Department ofAgriculture (USDA); and contri-
Permafrost Map of the USSR (1:2,500,000), 1996, Depart-
butions by a number of individuals.
mentofGeocryology,MoscowStateUniversity,16sheets
1.3 For all of the terms included, the source is included in
parentheses after the definition.
3. Significance and Use
1.4 This standard does not purport to address all of the
3.1 This terminology can be used to find the definitions of
safety concerns, if any, associated with its use. It is the
all of those terms which are used in association with frozen
responsibility of the user of this standard to establish appro-
materials, including rocks, soils, and water.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
4. Terminology
2. Referenced Documents 4.1 All of the definitions are consistent with those listed in
2 Terminology D653.
2.1 ASTM Standards:
D653 Terminology Relating to Soil, Rock, and Contained
active layer—the top layer of ground that is subject to annual
Fluids
freezing and thawing. (In the zone of discontinuous perma-
D4083 Practice for Description of Frozen Soils (Visual-
frost,theactivelayerisoftenunderlainbyunfrozenground.)
Manual Procedure)
active layer failure—any of several possible forms of slope
2.2 Other References:
failure in the active layer. NSIDC
Harris, S. A., French, H. M., Heginbottom, J. A., Johnston,
active layer thickness—the thickness of the top layer of
G. H., Ladanyi, B., Sego, D. C., and van Everdingen, R.
ground that is subject to annual freezing and thawing.
O.,1988, GlossaryofPermafrostandRelatedGround-Ice
NSIDC
Terms, Technical Memorandum,Associate Committee on
active rock glacier—a mass of rock fragments and finer
Geotechnical Research, Ottawa, Canada
material, on a slope, that contains an ice core or interstitial
Everdingen, Robert van, ed., 1998, revised January,
ice, and which shows evidence of recent movement.
2002, Multi-Language Glossary of Permafrost and Re-
NSIDC
adfreeze shear strength—theshearstressrequiredtoseparate
1 two objects that are bonded together by ice.
This terminology is under the jurisdiction of ASTM Committee D18 on Soil
adfreeze tensile strength—the tensile stress required to sepa-
and Rock and is the direct responsibility of Subcommittee D18.19 on Frozen Soils
and Rock.
rate two objects that are bonded together by ice. ASTM
Current edition approved Nov. 1, 2004. Published December 2004 DOI:
Z6948Z, NSIDC
10.1520/D7099-04.
adfreezing—theprocessbywhichobjectsarebondedtogether
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM by the ice formed between them. NSIDC
Standards volume information, refer to the standard’s Document Summary page on
aggradation of permafrost—see permafrost aggradation.
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D7099–04
aggradational ice—newly formed ice lenses, especially in the buried ice—ice formed on the ground surface and later
lower part of the active layer, which become incorporated covered by sediments.
intothepermafrostduetoaraisingofthepermafrosttableor candled ice—ice that has rotted or otherwise formed, by
a lowering of the permafrost base. meltingduringthespring,intolongcolumnarcrystalswhich
air freezing index—see freezing index. are very loosely bonded together. A distinctive “chiming”
air thawing index—see thawing index. sound accompanies movement during “ice-out.”
albedo—the fraction of the total solar radiation incident on a cave ice—ice formed in an open or closed cave. NSIDC
body that is reflected by it. clear ice—ice that is transparent and contains only a moderate
alpine permafrost—permafrost developed in temperate cli- number of air bubbles. ASTM Z6948Z
mate mountainous areas. ASTM Z6948Z closed-cavity ice—ice formed in a closed space, cavity, or
altitudinal permafrost limit—the lowest altitude at which cave, in permafrost. NSIDC
mountainpermafrostoccursinahighlandareaoutsideofthe closed-systemfreezing—freezingthatoccursunderconditions
general permafrost region. NSIDC that preclude the gain or loss of water by the system.
altitudinal permafrost zonation—the vertical subdivision of NSIDC
mountain permafrost into zones based on mean annual closed-system pingo—a pingo formed by the doming of
temperatures. NSIDC frozen ground due to the freezing of injected water. The
apparent heat capacity—the amount of heat required to raise water is provided by the expulsion of pore water during the
the temperature of a unit mass of frozen ground by one growth of permafrost. Closed-system pingos are found in
degree. It is expressed in Joules per kg per degree K. poorly-drained terrain in the continuous permafrost zone.
NSIDC NSIDC
approximate freezing index—the cumulative number of closed talik—a body of unfrozen ground occupying a depres-
degree-days below 0°C for a given period, calculated from sion in the permafrost table below a lake or river. NSIDC
the mean monthly temperatures for a given station without cloudy ice—ice that is translucent or relatively opaque due to
making corrections for positive degree-days in the spring the content of air or for other reasons, but which is
and fall. NSIDC essentially sound and nonpervious. ASTM Z6948Z
approximate thawing index—the cumulative number of coefficient of compressibility—the change in volume per unit
degree-days above 0°C for a given period, calculated from volume of a substance per unit increase in effective com-
the mean monthly temperatures for a given station without pressive stress, under isothermal conditions. NSIDC
making corrections for negative degree-days in the spring collapsescar—thatpartofapeatlandwherethewhole,orpart,
and fall. ofapeatplateauhasthawedandcollapsedtothelevelofthe
artificial ground freezing—the process of freezing earth surroundingland.Collapsesscarsarenotdepressionsbutare
materials by artificial means. marked by vegetation different from the peatland that was
banded cryogenic fabric—a distinct soil morphology in not underlain by permafrost. NSIDC
whichsoilparticlesformsubhorizontallayersastheresultof composite wedge—a wedge, containing both soil and ice, that
freezing and thawing. NSIDC shows evidence of both primary and secondary filling.
barrens—areas of discontinuous vegetation cover in the polar NSIDC
semi-desert of the High Arctic. NSIDC compressive strength—the load per unit area at which an
basal cryopeg—a layer of unfrozen ground, forming the basal unconfined cylindrical specimen of soil or rock will fail in a
portion of permafrost, in which the temperature is perenni- simple compression test. Commonly the failure load is the
ally below 0°C (32°F). NSIDC maximum that the specimen can withstand in the test.
basal cryostructure—the structural characteristics of a frozen D653
deposit of boulders that is saturated with ice. NSIDC conglomeric cryogenic fabric—a distinct soil micromorphol-
basal-layered cryostructure—the structural characteristics of ogy resulting from the effects of freezing and thawing, in
a frozen layered deposit of gravel and boulders that is which coarser soil particles form compound arrangements.
saturated with ice. NSIDC NSIDC
beaded stream—a characteristic pattern of small streams construction methods in permafrost—special procedures of
underlain by ice wedges. “Beads,” or pools, occur at design and construction that are required when engineering
junctions of wedges. The pools are linked by narrow works are undertaken in areas of permafrost.
channels. NSIDC contemporary permafrost—(1) newly formed permafrost in
bottom temperature of snow cover—temperature measured an area where surface temperatures have fallen below 0°C
at the base of the snow cover during mid- to late-winter (32°F); (2)permafrostthatisinthermalequilibriumwiththe
(February/March). The measurements are used in the BTS existing mean annual surface or sea-bottom temperature and
method to predict the presence or absence of permafrost. the geothermal heat flux. ASTM Z6948Z
NSIDC continuous permafrost—permafrost occurring everywhere
BTS method—a method to predict the presence or absence of beneath the exposed land surface throughout a geographic
permafrost in a mountainous area, using measurements of region, with the exception of widely scattered sites, such as
the bottom temperature of the snow in mid- to late-winter. newly-deposited unconsolidated sediments, where the cli-
NSIDC mate has just begun to impose its influence on the ground
D7099–04
thermal regime and will cause the formation of continuous cryosuction—a suction which develops in freezing or
permafrost. ASTM Z6948Z partially-frozen fine-grained materials due to temperature-
continuous permafrost zone—a major subdivision of a per- dependent differences in unfrozen water content. NSIDC
mafrost region, in which permafrost occurs everywhere cryotexture—the textural characteristics of frozen earth ma-
beneath the land surface, with the possible exception of terials cemented together with ice. NSIDC
widely scattered sites; both in North American (GPRGIT) cryotic ground—soil or rock in which the temperatures are
andinRussian(PermafrostMapoftheUSSR)usage:>80% 0°C, or below. NSIDC
of area underlain by permafrost. cryoturbate—a body of earth material moved or disturbed by
convection tube—a closed single-phase heat transfer device the action of frost. NSIDC
that removes heat from the ground whenever conditions are cryoturbation—(1) a collective term to describe all soil
appropriate to drive the internal convection cell. ASTM movements due to frost action; (2) irregular structures
Z6948Z formed in earth materials by deep frost penetration and frost
creep of frozen ground—the slow deformation that results action processes. ASTM Z6948Z, NSIDC
from long-term application of a stress too small to produce debris flow—a sudden and destructive form of landslide, in
failure in the frozen material. ASTM Z6948Z which loose materials on a slope, with at least half of the
creep strength—the failure strength of a material at a given particles being larger than sand, are mobilized by saturation
rate of strain or after a given period under deviatoric stress. and flow downwards. NSIDC
NSIDC deformability—the ability of a material to change its shape or
crust-like cryostructure—thestructuralpropertiesofafrozen size under the influence of an external or internal agency.
deposit of angular blocks that are coated with ice, while NSIDC
large spaces between the blocks are not filled with ice. degree-day—a unit of heat measurement equal to one degree
NSIDC of the variation of the mean temperature for a day from a
cryofront—the boundary between frozen and unfrozen given reference (or, base) temperature.
ground, as indicated by the position of the 0°C isotherm in degree of saturation—(1) the total degree of saturation of
the ground. NSIDC frozen soil is the ratio, expressed as a percentage, of the
cryogenesis—the combination of thermophysical, physico- volume of ice and unfrozen water in the soil pores to the
chemical, and physico-mechanical processes that occur in volume of the pores; (2) the degree of saturation of frozen
freezing, frozen, and thawing earth materials. NSIDC soil by ice, expressed as a percentage, is the ratio of the
cryogenic aquiclude—a frozen layer of ground with suffi- volume of ice in the soil pores to the volume of the pores.
ciently low permeability as to act as a confining bed for an NSIDC
aquifer. NSIDC density of frozen ground—the ratio of mass per unit of
cryogenic fabric—the distinct soil micromorphology which volume of frozen earth materials.
results from the effects of freezing and thawing processes. depth of seasonal frost penetration—themaximumthickness
NSIDC of the seasonally frozen layer. NSIDC
cryogenic temperature—the term can apply to temperatures depth of thaw—the distance from the ground surface down-
below−50°Cbutisusuallyusedforthosetemperaturesclose ward to frozen ground at any time during the thaw season.
to absolute zero (−273°C). NSIDC ASTM Z6948Z
cryolithology—the study of the genesis, structure, and lithol- depth of zero annual amplitude—the distance from the
ogy of frozen earth materials. NSIDC groundsurfacedownwardtothepointbeneathwhichthereis
cryopedology—the study of soils at temperatures below 0°C. virtually no annual fluctuation in the mean ground tempera-
cryopeg—alayerofunfrozengroundinwhichthetemperature ture. ASTM Z6948Z
is perennially below 0°C. In general, the freezing of such desiccation crack—a crack or fissure in fine-grained soil
layers is prevented due to the depression of the freezing material resulting from shrinkage during drying. NSIDC
point by solids dissolved in the pore water. desiccation polygon—a closed, multi-sided, pattern in the
cryoplanation—the process through which cryoplanation ter- ground formed by desiccation cracks in fine-grained soils.
races form. NSIDC NSIDC
cryoplanation terraces—hillside benches or table-like sum- design depth of frost penetration—(1) in North American
mitsurfaceswhicharethoughttohaveresultedfromintense usage: the mean of the three largest depths of seasonal frost
frost wedging associated with snowbanks.These are usually penetration measured during the
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