A coal seam that has separated into two or more layers which may, or may
not, rejoin some distance away. Syn:coal split
See also:multiple splitting
A device for sampling fine ore, consisting of a fork in which the prongs
are separate scoops, each scoop being the same width as the open spaces
between.
A type of seismic spread in which the shot point is at the center of the
arrangement of geophones. It is commonly used for continuous profiling and
for dip shooting. Syn:straddle spread; symmetric spread. AGI
A two-piece sprocket that can be assembled on a shaft without removing the
shaft bearings. Nichols, 1
a. A system of ventilation in which air is split along the airways or at
the face. See also:natural splitting; controlled splitting.
b. Historically, a combination of warm air heating and radiator heating.
Also used for other combinations, such as hot water steam, steam warm air,
etc. Strock, 2
See:split
a. Parting of a coalbed into two or more benches separated by other rocks.
AGI
b. In mine ventilation, the practice of connecting airways in parallel by
dividing the total air flow among them. Hartman, 2
c. Abrasion of a rock fragment resulting in the production of two or three
subequal parts or grains. AGI
d. The property or tendency of a stratified rock of separating along a
plane or surface of parting. AGI
e. The sampling of a large mass of loose material (e.g., a sediment) by
dividing it into two or more parts; e.g., quartering. AGI
A knife used for splitting leather or for diamond cleaving.
Standard, 2
A method of mining pillars seldom followed. A room is first driven through
the pillars, splitting them into smaller blocks. The pockets are turned at
right angles and are driven into the blocks. This method is really gouging
the pillars and is wasteful. Lewis
See:ventilation; splitting.
Arkansas. A shot put into a large mass of coal detached by a previous
blast. See also:block hole
See:soil sampler; split-barrel sampler.
See:soil sampler; split-barrel sampler. CF:solid-barrel sampler
A monoclinic mineral, LiAlSi2 O6 ; pyroxene group; prismatic
cleavage; in granite pegmatites in crystals up to scores of meters long
(called logs); a source of lithium; may be of gem quality (lavender
kunzite, green hiddenite). Formerly called triphane.
Syn:lithia amethyst; lithia emerald.
Overburden, nonore, or other waste material removed in mining, quarrying,
dredging, or excavating. See also:waste
a. A term common in surface mining to designate the accumulation of
overburden. BCI
b. Underground refuse piled outside. BCI
c. That part of a mine from which coal has been removed and the space more
or less filled up with waste. BCI
d. To leave coal and other minerals that are not marketable in a mine.
See also:spoil heap
An earthen dike forming a depression in which returns from a borehole can
be collected and retained. Long
a. The pile of dirt produced by mining operations and stacked at the
surface of a mine either in conical heaps or in layered deposits.
Syn:dump; tip. Nelson
b. A pile of refuse material from an excavation or mining operation; e.g.,
a pile of dirt removed from, and stacked at the surface of, a mine in a
conical heap or in layered deposits, such as a tip heap from a coal mine.
See also:spoil bank
The spontaneous heating and burning of small coal, carbonaceous shale, and
perhaps iron pyrites in spoil heaps. Nelson
See:waste dump
The reservoir formed by a spoil dam in which the returns from a borehole
collect and are retained. CF:sludge pit; sump. Long