A small locomotive used to move cars in and about mines and quarries.
Fay
To cut into the floor of a roadway to obtain more headroom.
Fraenkel
Said of layered silicates having two-thirds of the voids in the octahedral
layer filled, generally with trivalent cations. CF:trioctahedral
A monoclinic mineral, CaMgSi2 O6 ; pyroxene group; white to
light green; in metamorphic rocks, esp. contact metamorphosed limestones;
where transparent, a semiprecious gemstone. Symbol: Di or di.
See also:malacolite
A trigonal mineral, CuSiO2 (OH)2 ; emerald green; in the
oxidized zones of copper deposits; a source of copper. Also called emerald
copper, Zaire emerald.
A group of plutonic rocks intermediate in composition between acidic and
basic, characteristically composed of dark-colored amphibole (esp.
hornblende), acid plagioclase (oligoclase, andesine), pyroxene, and
sometimes a small amount of quartz; also, any rock in that group; the
approximate intrusive equivalent of andesite. Diorite grades into
monzonite with an increase in the alkali feldspar content. Etymol: Greek
diorizein, to distinguish, in reference to the fact that the
characteristic mineral, hornblende, is usually identifiable
megascopically. CF:dolerite; gabbro. See also:diabase
A term that has been used somewhat in the Western United States for
manganese ore. Hess
a. The angle at which a bed, stratum, or vein is inclined from the
horizontal, measured perpendicular to the strike and in the vertical
plane. See also:pitch; hade; angle of dip; apparent dip. CF:plunge
Lewis
b. To be inclined or dip at an angle.
c. The angle of a slope, vein, rock stratum, or borehole is measured from
the horizontal plane downward. Long
d. The direction of the true or steepest inclination. Mason
e. The lower workings of a mine. Hudson
f. The slope of layers of soil or rock. Nichols, 1
g. A dip entry, dip room, etc. A heading driven to the full rise in steep
mines. Fay
h. In terrestrial magnetism, the angle formed by the lines of total
magnetic force and the horizontal plane at the Earth's surface; reckoned
positive if downward. See also:apparent dip; full dip. Hy
i. In mines, the increase in depth of a moored mine case, due to current
force against the case and cable. Hy
Any of a number of methods of converting observed seismic arrival time
values to the dip of a reflector; most commonly the conversion of delta T
values to dip values by a conversion factor based upon the geometry of the
seismic array and approximate seismic propagational velocity. AGI
An instrument to measure magnetic intensity by means of a magnetic needle
fixed to swing in a vertical plane so that it can readily be deflected
downward by magnetic materials. Used to explore for subsurface deposits
containing magnetic materials. May also be called dip needle, dipping
compass, dipping needle, doodle bug magnetometer. Long
A map that shows stratified formations in their original position before
movement.
In cutting out blocks of stone, the cut that follows a line at right
angles to the strike.
An entry driven downhill so that water will stand at the face. If it is
driven directly down a steep dip it becomes a slope. See also:entry;
slope.
See:aclinic line
A face proceeding toward the dip of the seam. Briggs
A fault that strikes approx. perpendicular to the strike of the bedding or
cleavage. CF:oblique fault; strike fault. Billings
A drift inclined along the dip of a coal seam. Webster 3rd
a. A mine level connecting an engine shaft with the rooms or chambers.
Standard, 2
b. The main level, drift, or slope.
A joint that strikes approx. perpendicularly to the strike of the bedding
or cleavage. Billings
a. An instrument used to record the amount and direction of the dip of
strata exposed in the sides of a borehole. BS, 9
b. See:dipmeter
A dipmeter measures both the amount and direction of dip by readings taken
in the borehole and can be operated by using either self-potential or
resistivity measurements. Sinclair, 3