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cross-bedded

Having minor beds or laminae inclined to the main planes of
stratification, e.g., cross-bedded sandstone.

crossbedding

a. The quality or state of being crossbedded. A crossbedded structure.
Webster 3rd
b. Lamination, in sedimentary rocks, confined to single beds and inclined
to the general stratification. Caused by swift local currents, deltas, or
swirling wind gusts, and esp. characteristic of sandstones, both aqueous
and eolian. Syn:cross lamination
c. Crossbedding is generally truncated by the overlying stratum. However,
at the base of the crossbedded formation, the crossbedding is not
truncated, but it approaches the contact with the underlying stratum in a
broad tangential curve. Forrester
d. The arrangement of laminations of strata transverse or oblique to the
main planes of stratification of the strata concerned; inclined, often
lenticular, beds between the main bedding planes. It is found only in
granular sediments. AGI
e. Syn:inclined bedding
only in profiles at right angles to the current direction. AGI

cross-bladed chisel bit

Syn. for cross chopping bit. Long

cross-chopping bit

Bit with cutting edges made by two chisel edges crossing at right angles
with the intersection of chisel edges at the center of the bit face. Used
to chop (by impact) lost core or other obstructions in a borehole. Also
called cross bit; cross-bladed chisel bit; cruciform bit. Long

cross conveyor

Any conveyor used for transporting ore or waste from one room or working
place through a crosscut to an adjacent room or working place. Used
principally where the cross conveyor receives ore or waste from a conveyor
and delivers it to another conveyor or a car. Jones, 1

crosscut

a. A small passageway driven at right angles to the main entry to connect
it with a parallel entry or air course.
b. A tunnel driven at an angle to the dip of the strata to connect
different seams or workings. Nelson
c. A crosscut may be a coal drivage. See also:pillar-and-stall
Nelson
d. An underground passage directed across an orebody to test its width and
value or from a shaft to reach the orebody. See also:level crosscut;
cross. Nelson
e. A horizontal opening driven across the course of a vein or in general
across the direction of the main workings. A connection from a shaft to a
vein. Syn:cut-through
f. In room-and-pillar mining, the piercing of the pillars at more or less
regular intervals for the purpose of haulage and ventilation.
Syn:breakthrough
g. In general, any drift driven across between any two openings for any
mining purpose.
h. A borehole directed so as to cut through a rock strata or ore vein
essentially at right angles to the dip and strike of the rock strata, a
vein, or a related structure. Long
i. See:stenton

crossed belt

A driving belt that has a twist between the driving and the driven pulleys
causing a reversal of direction. Crispin

crossed nicols

a. In optical mineralogy, an anisotropic crystal is interposed between the
nicol prisms to observe its optical interference effects. The petrographic
microscope is normally used with nicol prisms (or equivalent polarizing
devices) in the crossed position. AGI
b. Nicols is often capitalized (crossed Nicols). Two nicol prisms placed
one in front of the other, or one below the other, and so oriented that
their transmission planes for plane-polarized light are at right angles
with the result that light transmitted by one is stopped by the other
unless modified by some intervening body. Webster 3rd
c. In polarized-light microscopy, the arrangement where the permitted
electric vectors of the two nicol prisms are at right angles.
See also:crossed polars

crossed polars

A common standard configuration used in polarized-light microscopy with
the substage polarizing filter (polarizer) permitting plane polarized
light with its electric vector in an east-west direction and the
above-stage polarizing filter (analyzer) permitting plane polarized light
with its electric vector in a north-south direction. Under these
conditions all light is absorbed by the two polars. Introduction of any
anisotropic transparent material into the light path repolarizes light
between the polars so as to generate interference colors and other effects
visible in the microscope ocular. See also:crossed nicols

crossed twinning

Repeated or polysynthetic twinning according to two twin laws with twin
planes angled to one another and with twin domains so intimate that they
appear overlapping in thin section; most notable in the feldspar and
feldspathoid minerals, esp. microcline. Syn:quadrille twinning;
gridiron twinning; cross-hatched twinning.

cross entry

a. An entry or set of entries, turned from main entries, from which room
entries are turned. Federal Mine Safety
b. A horizontal gallery driven at an angle or at right angles to a main
entry. Nelson

cross face

A coal face having a general direction between end and bord line.
TIME

cross fault

A fault that strikes diagonally or perpendicularly to the strike of the
faulted strata. AGI

cross fiber

Veins of fibrous minerals, esp. asbestos, in which the fibers are at right
angles to the walls of the vein. CF:slip fiber

cross frog

A frog adapted for railroad tracks that cross at right angles.
Webster 2nd

crossgate

a. A gate road driven at an angle off the main gate in longwall mining, to
form new intermediate gates or new faces inside a disturbance. Well-sited
crossgates result in reduction of inby conveyors and in roadway
maintenance. Nelson
b. Eng. See:crossheading
c. York. Short headings driven on the strike end at right angles to the
main gates or roads. Fay

cross gateway

Aust. A road, through the goaf, that branches from the main gateway.

cross-hatched twinning

See:crossed twinning

crosshead

a. A runner or framework that runs on guides, placed a few feet above the
sinking bucket to prevent it from swinging too violently. Fay
b. A beam or rod stretching across the top of something; specif., the bar
at the end of a piston rod of a steam engine, which slides on the ways or
guides fixed to the engine frame and connects the piston rod with the
connecting rod. Fay

crosshead guide

A guide for making the crosshead of an engine move in a parallel line with
the cylinder axis. Standard, 2

crossheading

a. A passage driven for ventilation from the airway to the gangway, or
from one breast through the pillar to the adjoining working. Also called
cross hole; cross gateway; headway. Fay
b. One driven from one drift or level across to another to improve
ventilation. Pryor, 3
c. A heading driven at an angle off the main level to cut off stalls or
intermediate headings, and form new ones on the face side of the heading.
Also called oblique heading; cutting-off road. Nelson
d. Eng. A road in longwall working to cut off the gateways. Syn. for
crossgate; slope. Also called crossbow; crossend. SMRB