A caustobiolith formed by the direct accumulation of vegetal matter; e.g.,
peat, lignite, and coal. AGI
a. Fragmented rock materials, derived from the sidewalls of a borehole,
that obstruct the hole or hinder drilling progress.
b. To allow a mine roof to fall without retarding supports or waste packs.
c. A falling in of the roof strata, sometimes extending to the surface and
causing a depression therein. Also called cave-in.
d. The partial or complete failure of borehole sidewalls or mine workings.
Long
e. Collapse of an unstable bank. Nichols, 2
f. A natural cavity, recess, chamber, or series of chambers and galleries
beneath the surface of the Earth, within a mountain, a ledge or rocks,
etc.; sometimes a similar cavity artificially excavated.
See also:cavity
There are two distinct types of caved stopes. In the first, the ore is
broken by caving induced by undercutting a block of ore. In the second,
the ore itself is removed by excavating a series of horizontal or inclined
slices, while the overlying capping is allowed to cave and fill the space
occupied previously by the ore. The first type comprises the caving
methods of mining, while the second comprises the top-slicing method.
A depression at the surface, caused by a fall of the roof in a mine.
Fay
Collapse of the walls or roof of a mine excavation. Pryor, 3
The partial or complete collapse of the walls of a borehole.
Brantly, 1
A linear area inby the last solid ground, in a longwall-type mine, where
the roof or back caves behind the retreating excavation.
Federal Mine Safety
See:cave onyx
A compact banded deposit of calcite or aragonite found in caves, capable
of taking a high polish and resembling true onyx in appearance.
See also:dripstone; onyx marble; travertine. Syn:cave marble
AGI
a. Eng. A thief who steals ore or coal at a mine. Standard, 2
b. The officer appointed to guard a mine. Standard, 2
c. A person whose hobby is exploring caves. Also called a spelunker.
Schieferdecker
Said of an area or geologic formation, such as limestone, that contains
caverns, or caves. Said of the texture of a volcanic rock that is coarsely
porous or cellular. AGI
a. To draw lots at stated periods--by miners to determine the places in
which they will work for the following period. Fay
b. A type of heavy sledge with one blunt and one pointed end. Used for
rough shaping stone at a quarry. Crispin
a. A stoping method in which ore is broken by induced caving. This may be
achieved by (1) block caving, including caving to main levels and caving
to chutes or branched raises; or (2) sublevel caving. See also:stope
b. In coal mining, the practice of encouraging the roof over the waste to
collapse freely so that it fills the waste area, thereby avoiding the need
to pack. In metal mining, caving implies the dropping of the overburden as
part of the system of mining. See also:block caving; sublevel caving;
top slicing. Nelson
c. The failure and sloughing in of sidewalls of boreholes, mine workings,
or excavations. Long
d. Fall of rock underground. See also:cavings
See:chute caving
Rock formations that will not stand in the walls of an underground opening
without support, such as that offered by cementation, casing, or timber.
Long
A borehole in which fragments of the material making up the walls of the
hole slough so much that the borehole cannot be kept open without the use
of casing or cementation. Long
Fragments of borehole wall-rock material that fall into a borehole,
sometimes blocking the hole, and which must be washed or drilled out
before the borehole can be deepened. See also:caving
a. A method of mining in which the support of a great block of ore is
removed, allowed to cave or fall, and in falling to be broken sufficiently
to be handled; the overlying strata subside as the ore is withdrawn. There
are several varieties of the system. See also:block caving; fall;
top slicing and cover caving; top slicing combined with ore caving.
b. Longwall coal mining in which excavated space (gob) is left to
collapse. See also:sublevel
See:block caving
The formation and instantaneous collapse of innumerable tiny voids or
cavities within a liquid subjected to rapid and intense pressure changes.
Cavitation produced by ultrasonic radiation is sometimes used to give
violent localized agitation. That caused by severe turbulent flow often
leads to cavitation damage. ASM, 1
The noise produced in a liquid by the collapse of bubbles that have been
created by cavitation. Hy