Geoscience Reference
In-Depth Information
Fig. 3.6
Gasoline-powered
drill rig with a SIPRE core
barrel for sampling
permafrost in arctic Alaska.
The drill rig is carried on a
sledge that is pulled by a
snow machine (Photo by
J. Kimble)
3.3
Laboratory Characterization of Cryosols
Cryosols, as with all soils, often require laboratory characterization, including
physical, chemical, mineralogical, and micromorphological analyses. These methods
are described in Burt (
2004
) and similar manuals.
3.3.1
Physical Analyses
Key physical properties that are analyzed include particle-size distribution (includ-
ing further fractionation of clay, silt, or sand for mineralogical analysis) and bulk
density. Water retention at 1,500 kPa may be measured and, when divided by the
clay content, yields a rough measure of the potential water-holding capacity of the
soil. The coeffi cient of linear extensibility (COLE) is a measure of shrink-swell
capacity and is calculated from bulk density measured moist (at 33 kPa) and oven
dry. Reynolds' dilatancy is an engineering test that measures the tendency of a com-
pacted material to dilate (expand in volume) as it is sheared.