a. A transverse wave propagated along the boundary of two elastic media
that both have rigidity; i.e., both media must be capable of propagating
transverse waves. AGI
b. A surface seismic wave in which the particles of an elastic medium
vibrate transverse to the direction of the wave's travel, with no vertical
component. AGI
c. A type of surface wave having a horizontal particle motion that is
transverse to the direction of propagation. Its velocity depends only on
density and rigidity modulus, and not on bulk modulus. It is named after
A.E.H. Love, the English mathematician who discovered it. Syn:Q wave;
Querwellen wave. AGI

The mineral group imandrite, kazakovite, koashvite, lovozerite,
petarasite, tisinalite, and zirsinalite.

a. A former stream channel in a coalbed, filled with sandstone, clay, and
shale. CF:cutout
b. A general term for such features as a structural basin, a syncline, a
saddle, or a sag. CF:high
c. Indicates that a crystal structure is the low-temperature dimorph for
the crystal compound.

low-alumina silica brick

Special brick in which the total alumina, titania, and alkali are
significantly lower than in regular silica brick.

low-angle fault

A fault with a dip of 45 degrees or less. CF:high-angle fault
AGI

low bed

A machinery trailer with a low deck. Nichols, 1

low blast

A blast delivered to a smelting furnace at low pressure.
Standard, 2

low coal

Coal occurring in a thin seam or bed. Fay

low-deflagrating explosive

Another name for black powder. Kentucky

Lowden drier

Mechanized drying floor used for ores or concentrates. Reciprocating rakes
move the material gently over steel plates heated from below.
Pryor, 3

low-density explosive

Explosive designed for use in mining, where it is required to blast with
the least amount of shattering and/or to reduce explosive cost. The
density of ordinary explosives may be decreased by (1) loose packing, (2)
an alteration in the granular state of the ammonium nitrate, and (3) the
impregnation of woodmeal or suitable substitutes. By decreasing the
density of an explosive the same weight of explosive is used, but owing to
its greater bulk the explosive effects are distributed over a greater
area, thus producing a less shattering effect.

low-discharge ball mill

One with a substantial downslope between the trunnion-high feed end and
the peripheral discharge end. This facilitates the brisk movement of ore
through the mill. Pryor, 3

low doors

Scot. The lowest of two or more landings in a shaft. Fay

low-duty fire clay brick

A fire-clay refractory having a pyrometric cone equivalent not lower than
19 and a minimum modulus of rupture of 600 psi (4.1 MPa). ARI

loeweite

A trigonal mineral, Na₁₂ Mg₇ (SO₄ )₁₃ .15H
₂ O ; white; water soluble. Also spelled loeweite.

lower

Pertaining to rocks or strata that are normally below those of later
formations of the same subdivision of rocks. The adj. is applied to the
name of a chronostratigraphic unit (system, series, stage) to indicate
position in the geologic column and corresponds to early as applied to the
name of the equivalent geologic-time unit; e.g., rocks of the Lower
Jurassic System were formed during the Early Jurassic Period. The initial
letter of the term is capitalized to indicate a formal subdivision (e.g.,
Lower Devonian) and is lowercased to indicate an informal subdivision
(e.g., lower Miocene). The informal term may be used where there is no
formal subdivision of a system or of a series. CF:upper; middle.
AGI

lower break

The lower bend of either a terrace or a monocline, also known as the foot
or the lower change of dip. See also:foot

lowering conveyor

Any type of vertical conveyor for lowering objects at a controlled speed.
See also:arm conveyor; suspended tray conveyor;
vertical reciprocating conveyor.

lowering skips

Used in some river tipples to let the coal down into the barges. Also
known as weigh pans. Mitchell