An elongated zone of the Earth's crust subjected to relatively great
structural deformation. CF:geosyncline
A hand-loaded, hoist-operated hauler used principally in certain central
Pennsylvania coal mines. It is essentially a chain-and-flight conveyor of
exceptional width, with high sideboards, mounted on wheels for operation
on mine track, with motive power supplied by a hoist mounted on the
chassis of the machine. The conveyor chain and flights can be moved in the
bed of the machine to assist in loading or unloading. The hoist rope can
be attached to props at the face and near the dumping point to provide
anchorage when the conveyor is moved. Jones, 1
A crane driven by gasoline, diesel, or electric motor, traveling on
crawler tracks, pneumatic tires or solid rubber tires, and capable of
moving in any direction under its own power. Hammond
A drill unit mounted on wheels or crawl-type tracks to facilitate moving.
Long
Applied to all equipment that is self-propelled or that can be towed on
its own wheels, tracks, or skids.See also:transportable equipment
Nelson
A platform hoist which is mounted on a pair of pneumatic-tired road
wheels, so that it can be towed from one site to another. This type of
hoist has been developed for use in house and flat construction.
See also:platform hoist
A self-propelling machine capable of lifting material off the bottom and
placing it in a mine car, conveyor, or other means of transportation.
Jones, 1
Syn:moss agate
A Cornish term for zinc blende; also called wild lead. See:sphalerite
Fay
See:sphalerite
A basic chromate of lead.
a. The mineral composition of a rock, usually expressed in weight or
volume percentages. Adj: modal. CF:norm
b. The value or group of values that occurs with the greatest frequency in
a set of data; the most typical observation. CF:mean
a. A facsimile in three dimensions--a reproduction in miniature of the
surface and underground workings of a mine, showing the shafts, tunnels,
crosscuts, etc., in all their details. From its very nature, it does not
fall within any definition of the word map and it is a misapplication of
the term to call it a map, though it may far better serve the purpose in
hand. Ricketts
b. A unifying concept that explains or describes a complex phenomenon.
See also:mineral deposit model
The comprehensive testing of scale models of various structures, including
harbors and rivers to determine the behavior of the actual structure under
consideration. See also:photoelasticity
a. Person who shapes plaster of Paris, clay, etc., to form original models
used to make molds for producing ceramic ware.
b. Person who builds models used in model analysis.
Fine, plastic clay, esp. prepared for artists in modeling by kneading with
glycerin, or by other methods. Fay
A field term that, in accordance with an arbitrary scale established for
use in describing banded coal, denotes a frequency of occurrence of
vitrain bands comprising from 13% to 30% of the total coal layer.
CF:sparse vitrain; abundant vitrain; dominant vitrain. AGI
A method used in room-and-pillar mining where the lease requires at least
80% of recovery. Basically it consists of turning the rooms on 70-ft
(21.3-m) centers then working the room up 30 ft (9.1 m) wide and butting
it off at its completion, then withdrawing the remaining 40 ft (12.2 m) of
pillar immediately. Kentucky
modified room-and-pillar working
In froth flotation, reagent used to control alkalinity and to eliminate
harmful effects of colloidal material and soluble salts.
See also:modifying agent