A pegmatite body characterized by pneumatolytic-hydrothermal replacement
and rare minerals. Schieferdecker
A condition superimposed on simple pneumoconiosis by the effect of
tuberculosis lesions. Nelson
Layers or bands that are petrographic entities, recognizable visually as
bands or layers of coal that have distinctive physical appearance and
characteristic microstructural features from coal to coal. IHCP
A dike formed by two or more intrusions of different compositions into the
same fissure.
Explosives that contain a mechanical mixture of substances that consume
and give off oxygen with one or several simple explosives. They can be
regarded as mixed explosives with an addition of one or more simple
explosives as sensitizers, which makes for easier initiation of the
mixture and gives greater assurance of complete transformation.
Fraenkel
See:compound fold
a. A banded rock resulting from intimate penetration of magma (usually
granite) into adjacent rocks. See also:injection gneiss; migmatite.
b. Gneiss that is constituted of materials of at least two different
phases. CF:venite; veined gneiss. AGI
Any igneous intrusion that is composed of two or more injections of
different chemical and mineralogical composition.
CF:multiple intrusion
A map on which several levels of a mine are shown on a single sheet.
Horizontal projection of data from different elevations. McKinstry
Structural materials of metal alloys or plastics with built-in
strengthening agents that may be in the form of filaments, foils, or
flakes of a strong material. Hunt
One in which different parts, or stages, of the sample are reached by
differing methods. Pryor, 3
A sill composed of two or more intrusions having different chemical and
mineralogical compositions.
See:assembled stone
A comprehensive term that includes doublets, triplets, etc., in which a
stone consists of two or more parts either of the same or of different
materials cemented or otherwise joined together. Anderson
A large fracture zone, up to many tens of feet in width, consisting of
parallel ore-filled fissures and converging diagonals, the walls and the
intervening country rock of which have undergone some replacement.
A mixture of RDX and TNT that, when cast, has a density of 1.65 g/cm
3 and a velocity of 25,000 ft/s (7.6 km/s). It is useful as a
primer for blasting agents. Meyer
If two or more forces acting on a body can be replaced by a single force
the forces are said to have been compounded. This is known as composition
of forces. Morris
A planar or irregular surface by which parts of a twin crystal are united,
not necessarily parallel to a crystal face.
In compound compression, the work of compression is divided into two or
more stages or cylinders. In two-stage compression, air is compressed in
the first or low-pressure cylinder to a certain point, then forced into an
intercooler where it is cooled to approx. its original temperature, then
passes into the second or high-pressure cylinder, in which it is
compressed to the final or delivery pressure. The ratio of compression in
each cylinder of a two-stage compressor is equal to the square root of the
overall ratio of compression, i.e., the square root of the final absolute
pressure divided by the absolute atmospheric pressure. In three-stage
work, the ratio of compression in each cylinder is the cube root of the
overall ratio of compression. Also called stage compression. Lewis
An apparatus comprising three tiers of blanket tables, a shaking table,
and a mercury riffle for catching gold. Fay
A type of dredger combining the suction or suction cutter apparatus with a
bucket ladder. CTD