a. The mechanical wearing away of rock surfaces by friction and impact of
rock particles transported by wind, ice, waves, running water, or gravity.
Syn:corrasion
b. The wearing away of diamonds, drill-bit matrices, and drill-stem
equipment by frictional contact with the rock material penetrated or by
contact with the cuttings produced by the action of the drill bit in
drilling a borehole. Long
Hardness expressed in quantitative terms or numbers indicating the degree
to which a substance resists being worn away by frictional contact with an
abrasive material, such as silica or carborundum grits. Also called
abrasion resistance; wear resistance. Long
The percentage of a specially prepared 3-in by 2-in (76-mm by 51-mm)
sample of coke remaining on a 1/8-in (3.2-mm) mesh British Standards test
sieve after the sample of coke has been subjected to a standardized
abrasion procedure in a rotating drum. BS, 1
a. Any natural or artificial substance suitable for grinding, polishing,
cutting, or scouring. Natural abrasives include diamond, emery, garnet,
silica sand, diatomite, and pumice; manufactured abrasives include esp.,
silicon carbide, fused alumina, and boron nitride. AGI
b. Tending to abrade or wear away. AGI
A respirator designed to protect the wearer from inhalation or impact of,
and abrasion by, materials used or generated in abrasive blasting.
ANSI
A rock consisting of small, hard, sharp-cornered, angular fragments, or a
rock, the cuttings from which, produced by the action of a drill bit, are
hard, sharp-cornered, angular grains, which grind away or abrade the metal
on bits and drill-stem equipment at a rapid rate. Syn:abrasive ground
Long
Test employing a rotating abrasive wheel or plate against which specimens
are held. The specimens are abraded for a given number of revolutions, and
the weight of material lost is a measure of the abrasive hardness.
Lewis
See:abraumsalze
Ger. Mixed sulfates and chlorides of potassium, sodium, and magnesium
overlying the rock salt in the Stassfurt salt deposits.
Syn:abraum salts; stripping salt. Holmes, 2
An earthy, amorphous variety of crocidolite asbestos. Dana, 1
a. In chemistry, free from impurity or admixture. Hess
b. In physics, not dependent on any arbitrary standard. Hess
c. Frequently used in the trades to indicate a thing as being perfect or
exact. Abbrev. abs. Crispin
The geologic age of a fossil organism, rock, or geologic feature or event
given in units of time, usually years. Commonly used as a syn. of isotopic
age or radiometric age, but may also refer to ages obtained from tree
rings, varves, etc. Term is now in disfavor as it implies a certainty or
exactness that may not be possible by present dating methods; i.e., two
absolute ages for the same pluton may disagree by hundreds of millions of
years. CF:relative age
An absolute unit of pressure equal to 1 million times the pressure
produced on 1 cm2 by the force of 1 dyn. Fay
A measure of available energy per unit volume of explosive.
Syn:bulk strength
Geochronology in which the time-order is based on absolute age, usually
measured in years by radiometric dating, rather than on superposition
and/or fossil content as in relative chronology. AGI
During the 24 h of the day the difference between the maximum easterly and
maximum westerly values of the magnetic declination at any point.
Mason
The content of water vapor in air, expressed as the mass of water per unit
volume of air. CF:relative humidity
A line that has the properties of both constant pressure and constant
height above mean sea level. Therefore, it can be any contour line on a
constant-pressure chart, or any isobar on a constant-height chart.
Hunt
In law, an unqualified title to property and the unquestioned right to
immediate and unconditional possession thereof. Applies to mining claims
and properties. Standard, 2; Hess
A measure of possible flow of a standard liquid under fixed conditions
through a porous medium when there is no reaction between the liquid and
the solids. This measure is arbitrarily taken for isothermal viscous flow.
It can be duplicated with gases if tests are so conducted that
extrapolation to infinite pressure can be made; specific permeability.
Hess