a. To conduct the ventilation backward and forward through the workings,
by means of properly arranged stoppings and regulators. Fay
b. A seam of coal. Fay
c. To ventilate a number of faces in series. BS, 8
d. An unproductive vein as opposed to a lode.
e. The horizontal direction of a geologic structure. Syn:course of ore;
strike. Webster 3rd
Mine ventilation by the same air current, i.e., without splitting of air.
Nelson
a. A horizontal shoot. An older term. Nelson
b. See:chute; course.
The strike of a vein; direction of the horizontal line on which it cuts
the country rock.
The method of shovel operation in which no ground is hauled away. The
shovel simply stacks the ground on the opposite side from the working cut,
or it may turn entirely around, dumping the spoil on a bank behind.
Lewis
The control of ventilation in mines, as by doors, brattices, and
stoppings. Standard, 2
One rising freely through the cell during froth flotation.
Pryor, 4
A method used by companies for checking the amount of refuse in coal. The
refuse is picked daily from a few cars of run-of-mine coal, and when the
amount of refuse is considered unreasonable, it is shown to the miner and
the laborers. They may be suspended from work if the amount and size of
refuse is too high. Mitchell
In bituminous coal mining, one who examines mine cars of coal for
impurities, such as slate, rock, and dirt, by the courthouse system
(selecting cars at random for examination). Rejects, on basis of
inspection, any group or lot of cars containing too much impurity.
DOT
A form of asphaltum allied to gilsonite. Fay
Cornish miner, usually far from home, important to U.S. mining.
Pryor, 3
A statistical measure of the correlation between two variables. In
geostatistics, covariance is usually treated as the simple inverse of the
variogram, computed as the overall sample variance minus the variogram
value. These covariance values, rather than variogram values, are actually
used in kriging matrix equations for greater computational efficiency.
See:covellite
A hexagonal mineral, CuS ; metallic indigo blue with iridescent tarnish;
soft; a supergene mineral in copper deposits; a source of copper.
Syn:blue copper; covelline; indigo copper. See also:copper sulfide
a. The sedimentary accumulation over the crystalline basement.
See also:cover mass
b. The vertical distance between any position in strata and the surface or
any other position used as a reference. See:surface
c. The pattern or number of drill holes (pilot holes) deemed adequate to
detect water-bearing fissures or structures in advance of mine workings.
Syn:pilot-hole cover
d. Total thickness of material overlying mine workings or an orebody.
See also:burden; mantle; cover rock. CF:rock cover
Common term for arch brick used to line soaking-pit covers.
The area in advance of mine workings not adequately probed by pilot holes
to detect the presence of water-bearing fissures or structures.
Long
One of a group of boreholes drilled in advance of mine workings to probe
for and detect water-bearing fissures or structures. Long
The point at which the overburden meets the coal. BCI
The load due to the weight of the superincumbent rock. Issacson
The material overlying the plane of an angular unconformity.
See also:cover