a. See:thrust fault
b. A fault structure in which the displaced strata are doubled back upon
themselves. AGI
a. Scot. The material above the rock in a quarry. See also:overburden
Fay
b. Graphic data on a transparent or translucent sheet to be superimpossed
on another sheet (such as a map or photograph) to show details not
appearing, or requiring special emphasis, on the original. Also, the
medium or sheet containing an overlay. AGI
A tracing on which the workings in a seam are shown. A series of such
tracings allows the workings in several seams to be seen in their correct
horizontal relationship. Also called layover tracing (undesirable usage).
BS, 7
a. In general, a load or weight in excess of the designed capacity. The
term may be applied to mechanical and electrical engineering plants, to
loads on buildings and structures, and to excess loads on haulage ropes
and engines. Nelson
b. To apply an excessive pressure, by stretching beyond the yield point,
to a drill string and bit. CF:crowd
A loading machine of the power-shovel type for quarry and opencast
operations. It may be either pneumatic-tired or continuous-tracked. It
need not turn from the face to the truck if the latter can be spotted
parallel to the face. The bucket is filled, the machine retracted, and the
bucket swung over to the discharge point; used chiefly in sand and gravel
pits. Nelson
S. Afr. Mining a grade of ore above the average grade of the ore reserves.
This practice has the effect of leaving the lower grade ore in the
reserves. The opposite is undermining. Beerman
In refining blister copper by reducing its oxides through stirring a
molten bath of metal with a green timber pole, continuation of this
process until the desirable characteristic fracture of tough-pitch refined
metal is lost. Some reoxidation then becomes necessary.
See also:tough pitch
The superposition of a new set of structural features on an older set.
Syn:superprint; metamorphic overprint. AGI
A royalty or percentage of the gross income from production deducted from
the working interest. Wheeler, R.R.
The term applied to a royalty reserved in a sublease or assignment over
and above that reserved in the original lease. Ricketts
A winding or hoisting rope. Fay
Usually applied to endless rope haulage in which the rope is carried on
top of the mine cars, which may be either clipped or lashed to the rope.
See also:underrope haulage
See:overhaul
A special brake fitted to a towed vehicle that operates as soon as the
towing vehicle slows down. Hammond
A coupling that transmits rotation in only one direction, and disconnects
when the torque is reversed. Nichols, 1
A rock that contains silica in excess of that necessary to form saturated
minerals from the bases present. CF:saturated rock
A fishing tool for recovering lost drill pipe or casing.
Inst. Petrol.
Discharging over the side; e.g., by a dredge. Standard, 2
a. In reference to a mixture of material screened or classified into two
products of definite size limits, the larger is the oversize and the
smaller the undersize. See also:classifier
b. In quarry or opencast blasting, that size of rock or ore which is too
large to handle without secondary blasting. Nelson
A screen used to prevent the entry into a machine of large particles that
might interfere with its operation. Syn:guard screen; check screen.
BS, 5
a. Core cut by a thin-wall bit, as opposed to a standard-diameter core.
Long
b. A core the diameter of which is greater than a standard size.
Long