A mine surveyor. See also:spud
On a dredge, a pair of guide collars for a spud. Nichols, 1
a. A brace or prop. See also:sprag
b. A small vein branching from a main one. AGI
c. A rock ridge projecting from a sidewall after inadequate blasting.
Nichols, 1
d. A relatively short and small vein of quartz that cuts across the
bedding, in contrast to a saddle reef that more or less follows the
bedding. Nelson
See:triangular facet
A monoclinic mineral, Ca5 (SiO4 )2 (CO3 ) ;
dimorphous with paraspurrite; forms light gray granular masses resembling
limestone; at Velardena, Durango, Mexico; Scawt Hill, Ireland; Luna
County, NM; and Crestmore, CA.
Forest of Dean. A disintegrated stone.
In railroading, a short sidetrack connecting with the main track at one
end only. Standard, 2
A short branch valley. Nichols, 1
A term used in the slate industry with reference to roofing slate. A
square is a sufficient number of any size to lay 100 ft2 (9.29 m
2 ) of roof, allowing the standard 3-in (7.62-cm) lap. The
estimated weight of a square of 1/4-in (6.4-mm) slate is 1,000 lb (454
kg).
A long stabilizer of rectangular shape that when used properly gives a
super-packed-hole effect. Square drill collars are made primarily from
30-ft (9.14-m) steel bar stock with a diagonal measurement greater than
the hole diameter in which the collar will eventually be used. This collar
has proved successful in controlling rapid directional and deviational
changes in wells drilled in a disturbed-belt-type area. API, 2
A unit of measure representing the volume of water 1 ft (0.3 m) deep over
an area of 1 mile2 (2.6 km2 ). See also:acre-foot
Hammond
A set of timbers used to provide support in a stope or an underground
mine. Each timber set consists of a vertical post and two horizontal
members known as a cap and girt. The timber ends are sawed to allow
adjoining timbers to interlock. They are framed at mutual right angles,
and when joined with other sets form a continuous timber framework that
conforms to the irregular shape of the stope. The posts are 6 to 7 ft
(1.83 to 2.13 m) high, while the caps and girts are 4 to 6 ft (1.22 to
1.83 m) long. Caps and girts are placed on top of the posts, a line of
caps being at right angles to a line of girts. Square sets vary in
dimensions at different mines, but in general should give a clear opening
of at least 5 ft (1.52 m) each way between posts to afford sufficient
working space in the stope, and a clear height of 6-1/2 ft (1.98 m) is
about the minimum height desirable. This system of timber support can be
adapted to large and irregular orebodies resulting in an elaborate network
extending the full height and width of a stope.
A method of block caving in which the caved ore is extracted through
drifts supported by square sets. A retreating system is adopted.
Nelson
See:top slicing and cover caving
A method of stoping in which the walls and back of the excavation are
supported by a system of interlocking framed timbers (square set). A
square set of timber consists of a vertical post and two horizontal
members set at mutually right angles. The mining process is slow and only
enough ore is excavated to provide room for installation of each
successive set of timber. The stopes are usually mined out in floors or
horizontal panels, and the sets of each successive floor are framed into
the top of the preceding floor. Syn:alternate pillar and stope;
overhand vertical slice; underhand vertical slice.
CF:back-filling system
A method of mine timbering in which heavy timbers are framed together in
rectangular sets, 6 to 7 ft (1.83 to 2.13 m) high, and 4 to 6 ft (1.22 to
1.83 m) square, so as to fill in as the orebody is removed by overhand
stoping. Webster 3rd
a. A screw thread the cross section of which is square. Long
b. A robust type of screw thread that can transmit thrust in both
directions. Hammond
See:sublevel stoping
See:sublevel stoping