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load-out

To load coal or rock that is to be taken out of the mine. Fay

loadstar

See:lodestone

loadstone

Alternate spelling of lodestone. See also:lodestone

load transfer

The weight of the strata above every excavation is largely transferred to
the coal pillars or packs in the vicinity. Attempts are made to control
and facilitate this load transfer in the yield-pillar system and in double
packing. See also:abutment; pressure arch. Nelson

loam beater

A rammer used in making a loam mold. Standard, 2

loam cake

A disk of dried loam used to cover a loam mold; it has holes through which
melted metal is poured and air escapes. Standard, 2

loaming

A method of geochemical prospecting in which samples of soil or other
surficial material are tested for traces of the metal desired, its
presence presumably indicating a near-surface orebody. AGI

Lobbe Hobel

An earlier type of rapid plow traveling at 70 ft/min (21.3 m/min) across
the face. Nelson

Lobbert lagging

A lagging consisting of galvanized steel wire frames fastened to
underground haulageway supports by special wire fasteners to provide a
continuous lining. Nelson

lobs

Steps in a mine. Hess

local cell

A galvanic cell resulting from inhomogeneities between areas on a metal
surface in an electrolyte. The inhomogeneities may be of physical or
chemical nature in either the metal or its environment. See also:cell
ASM, 1

local current

A natural earth current of local origin, such as one arising from the
oxidation of a sulfide deposit. A term used in electrical prospecting.
AGI

local extension

The extension produced in a tensile test after the ultimate tensile stress
has been passed and concentrated on part of the gauge length where a neck
is formed. CTD

local indicator plant

Plants of wide geographic distribution having an affinity for absorbing
certain metallic elements from the soil and which can be used in
geochemical exploration to indicate presence of local concentrations of
metals. CF:universal plant indicator

local metamorphism

Metamorphism caused by a local process; e.g., contact metamorphism or
metasomatism near an igneous body, hydrothermal metamorphism, or
dislocation metamorphism in a fault zone. CF:regional metamorphism
AGI

local shear failure

Failure in which the ultimate shearing strength of the soil is mobilized
only locally along the potential surface of sliding at the time the
structure supported by the soil is impaired by excessive movement.
ASCE

local unconformity

An unconformity that is strictly limited in geographic extent and that
usually represents a relatively short period, such as one developed around
the margins of a sedimentary basin or along the axis of a structural trend
that rose intermittently while continuous deposition occurred in an
adjacent area. It may be similar in appearance to, but lacks the regional
importance of, a disconformity. CF:regional unconformity

local vent

A pipe or shaft to convey foul air from a plumbing fixture or a room to
the outer air. Crispin

local ventilation

Ventilation of the drives and headings in mines by use of the pressure
gradient of the main air current. Stoces

locatable minerals

A legal term that, for public lands in the United States, defines a
mineral or mineral commodity that is acquired through the General Mining
Law of 1872, as amended (30 U.S.C. 22-54, 161, 162, 611-615). These are
the base and precious metal ores, ferrous metal ores, and certain classes
of industrial minerals. Acquisition is by staking a mining claim
(location) over the deposit and then acquiring the necessary permits to
explore or mine. SME, 1

located

Delimited by having the boundaries ascertained and monumented on the
ground, identified by having a notice of location posted upon the land,
and further proclaimed to the public by having such notice of location
recorded in the manner customary under the rules for recording mining
claims. Ricketts