N. of Eng. The last rib or jud to come off a pillar. Fay
a. The locking device on a hoist hook, elevator, lifting bail, etc.
Long
b. The inner-tube locking and unlocking device in the head of a wire-line
core barrel. Long
a. Applied to the split rail and hinged switches. Syn:switch
Fay
b. Hinged switch points, or short pieces of rail that form rail crossings.
Fay
A mineral formed during the late stages of magmatic activity, between the
main stage of crystallization and the pegmatitic stage.
Thermal energy absorbed or emitted in a process (as fusion or
vaporization) other than change of temperature. CF:sensible heat
Webster 3rd
The amount of heat required to change 1 g of a substance at the
temperature of its melting point from the solid to the liquid state
without changing temperature. Morris
a. A hard heading that branches off a horizon, in horizon mining, along
the strike of the seams. It may be from 14 to 20 ft (4.3 to 6.1 m) wide.
At intervals of 1,000 to 1,500 yd (910 to 1,400 m) along the lateral,
crosscut roads are driven at right angles to intersect and develop the
coal seams. From the crosscuts, conveyor panels are opened out in the
seams. In general, the term lateral is also applied to any coal heading
driven in a sideways direction. Nelson
b. Belonging to the sides, or to one side. Fay
c. A horizontal mine working. Fay
d. Situated on or at, or pertaining to, a side. CTD
e. A conduit diverting water from a main conduit, for delivery to
distributaries. Seelye, 1
f. A secondary ditch. Seelye, 1
Cleavage parallel to the lateral planes. Webster 3rd
Any system of development in coal seams or thick orebodies in which
headings are driven horizontally across the coal or ore and connected to
main haulage drifts, entries, or shafts. There are many variations and
modifications depending on the thickness, shape, and inclination of the
deposit. See also:horizon mining
The horizontal distance by which a borehole misses its intended target.
Long
The angle of draw over a strike face or over workings in a flat seam.
Briggs
A theory of ore genesis formulated in the 18th century and passing in and
out of use since. It postulates the formation of ore deposits by the
leaching of adjacent wall rock. In current usage, convectively driven
fluids associated with cooling plutons are thought to have abstracted
metals from adjacent host rocks and transported them to new sites of
deposition, as in the formation of certain porphyry base-metal deposits.
See also:lithogene; segregated vein. AGI
Means whereby walls are braced either vertically or horizontally by
columns, pilasters, or crosswalls, or by floor or roof constructions,
respectively. ACSG, 1
A signal that is recorded on a seismogram later than the first arrival of
energy. Schieferdecker
Red residual soil developed in humid, tropical, and subtropical regions of
good drainage. It is leached of silica and contains concentrations
particularly of iron oxides and hydroxides and aluminum hydroxides. It may
be an ore of iron, aluminum, manganese, or nickel. Adj. lateritic.
Syn:latosol
The electrical resistivity of coal appears to decrease with ash content.
The laterlog measures what is virtually the true resistivity of the coal
and may ultimately provide information on seam quality. The laterlog uses
a sheet of current that is focused on each formation in succession and so
measures the resistivity of that formation only. The mud column or a salty
mud has no effect on the measured resistivity. The laterlog may be
measured by a seven- or three-electrode arrangement but the former is
preferred. Sinclair, 3
A specialized cementing material consisting of a portland-type cement,
latex, a surface-active agent, and water, having a setting time equivalent
to a neat portland-cement slurry. Latex cement shrinks less and is
tougher, stronger, less permeable, and more durable than portland cement.
Long
Trade name for a synthetic rubber fluid, which, when sprayed onto
underground stoppings, forms a tough nonflammable coating thus preventing
air feeding fires or heatings, or air leakages through doors, surface air
locks, and air crossings. Also called Latex sealant. Nelson
a. A board or plank sharpened at one end, like sheet piling, used in
roofing levels or in protecting the sides of a shaft through a stratum of
unstable earth. See:spill
b. A long, thin mineral crystal. AGI
A weak lath frame, surrounding a main crib, the space between being for
the insertion of piles. Fay
Refers to crystals with three distinctly different dimensions.
CF:acicular; tabular; rodlike; equant.