An instrument for measuring the elevation above sea level by determining
the atmospheric pressure through observing the boiling point of water.
Standard, 2
Any map showing relief by means of contours, hachures, shading, tinting,
or any other convention. AGI
The science of determining, by any method, elevations on the Earth's
surface with reference to sea level; e.g., barometric hypsometry in which
elevations are determined by means of mercurial or aneroid barometers.
AGI
a. A lag in the return of an elastically deformed body to its original
shape after the load has been removed. AGI
b. The property that a rock is said to exhibit when its magnetization is
nonreversible. Syn:magnetic hysteresis
c. A phase lag of dielectric displacement behind electric-field intensity,
due to energy dissipation in polarization processes. AGI
Entire pattern of magnetization showing how a body with magnetic
susceptibility can remain polarized after the disappearance of the
original magnetizing force.
Separation by alternating current that depends on magnetic properties of
coercive force and remanence.
An orthorhombic mineral, (UO2 )6 O2 (OH)8 .6H
2 O ; acicular with perfect basal cleavage; in cavities, as an
alteration product of uraninite at Kasolo, Congo, and Wolsendorf, Bavaria.
Water in the solid state; specif. the dense substance formed in nature by
the freezing of liquid water, by the condensation of water vapor directly
into ice crystals, or by the recrystallization or compaction of fallen
snow. It is colorless to pale blue or greenish blue, usually white from
included gas bubbles. At standard atmospheric pressure, it is formed at
and has a melting point of 0 degrees C; in freezing it expands about one
eleventh in volume. Ice commonly occurs in hexagonal crystals, and in
large masses is classed as a rock. AGI
A large, massive piece of floating or stranded glacier ice of any shape,
detached (calved) from the front of a glacier into a body of water. An
iceberg extends more than 5 m above sea level and has the greater part of
its mass (four-fifths to eight-ninths) below sea level. It may reach a
length of more than 80 km. AGI
A dense frozen mixture of sand, rock fragments, and ice. AGI
See:till
See:obsidian
See:Iceland spar
A transparent, pure, optically clear variety of calcite principally in
Iceland in vugs and cavities in basalt; formerly used in optical
instruments such as nicol prisms, but has been replaced by artificial
materials such as polaroid plates. Syn:Iceland crystal;
optical calcite.
The period of time from freezeup to breakup of ice. AGI
An ice obstruction formed by a circulation medium freezing inside the
drill-rod couplings while the rods are racked up or standing in the drill
derrick or tripod in extremely cold weather. Such plugs may loosen when
rods are lowered into the borehole and may be ejected from the open end of
the rod with enough force to injure drill crewmembers severely.
Long
See:debacle
A glacier of considerable thickness and more than 50,000 km2 in
area, forming a continuous cover of ice and snow over a land surface,
spreading outward in all directions and not confined by the underlying
topography; a continental glacier. Ice sheets are now confined to polar
regions (as on Greenland and Antarctica), but during the Pleistocene Epoch
they covered large parts of North America and northern Europe. AGI
A white transparent variety of orthoclase. Syn:sanidine
See:cryolite
See:trapezohedron