A process used formerly for the recovery of manganese dioxide in making
chlorine from hydrochloric acid in a stoneware still, by adding lime to
the still liquor and oxidizing with air to precipitate a mud containing
calcium manganite and yielding chlorine when recirculated and treated with
hydrochloric acid. Webster 3rd
a. A borehole or shaft sunk into the ground for the following purposes:
obtaining water, oil, gas, or mineral solutions from an underground
source; introducing water, gas, or chemical reagent solutions under
pressure into an underground formation; or removing the leachate from such
an operation. See also:borehole mining
b. A slot in the front of a hydraulic dredge hull in which the digging
ladder pivots. Nichols, 1
c. A hollow cylinder of reinforced concrete, steel, timber, or masonry
built in a hole as a support for a bridge or building. Webster 3rd
d. Commonly used as a syn. for borehole or drill hole, esp. by individuals
associated with the petroleum-drilling industry. Long
e. A wall around a tree trunk that protects it from fill.
Nichols, 1
f. An artificial excavation (pit, hole, tunnel), generally cylindrical in
form and commonly walled in, sunk (drilled, dug, driven, bored, or jetted)
into the ground to such a depth as to penetrate water-yielding rock or
soil and to allow the water to flow or to be pumped to the surface; a
water well, originally applied to natural springs or pools, esp. mineral
spas. See also:artesian well; deep well.
g. The crucible of a furnace or a cavity in the lower part of some
furnaces to receive falling metal.
h. The small dark nonreflecting area in the center of a fashioned stone,
esp. in a colorless diamond cut too thick.
i. A vertical opening through the hull of a ship in which drill pipe or
mining machinery is lowered to the seafloor, rather than being lowered
over the side of the ship. Also called: moonpool.
A triangle that is equilateral or nearly so. In such a triangle any error
in the measurement of an angle will be reduced to a minimum.
Hammond
A sample of rock penetrated in a well or other borehole obtained by use of
a hollow bit that cuts a circular channel around a central column or core.
AGI
Rock chips cut by a bit in the process of well drilling and removed from
the hole by pumping or bailing. Well cuttings collected at closely spaced
intervals provide a record of the strata penetrated. AGI
Hole drilled by means of an apparatus known as a well drill, or similar to
that, and used in groups for blasting on a comparatively large scale. Such
holes are usually 5 in or 6 in (12.7 cm or 15.2 cm) in diameter and from
30 to 150 ft (9.1 to 45.7 m) deep.
A transparent lighting device used as a main lighting device in mines. Its
distribution characteristics are simple, since there is no control of
light other than that provided by the interior of the upper part of the
fitting, which absorbs a large proportion of the upward flux component
from the lamp and reflects the remainder. It is usually to be found spaced
at intervals of 20 to 50 ft (6.1 to 15.2 m), 6 to 7 ft (1.83 to 2.13 m)
high, along the centerline of roads 12 to 14 ft (3.66 to 4.27 m) wide. In
general, the most noticeable effect of such a layout is glare.
Roberts, 2
a. A large-diameter (about 6 in or 15 cm) vertical hole used in quarries
and opencast pits for heavy explosive charges. Nelson
b. Change room. Hess
A method of quarry blasting in which the explosive charges are placed in
rows of vertical holes. The loading ratio varies from about 3 st of rock
per pound (6 t/kg) of explosive up to about 7 st (14 t/kg) under favorable
conditions. Deck loading is usually employed, and a powerful gelatinous
explosive is loaded at the bottom of the holes. Nelson
This type of blasting is virtually benching on a large scale. The depth
and burden of the holes are much greater, and in consequence, the hole
diameter must also be increased to ensure sufficient concentration of the
explosive charge. Wellhole blasting is used in limestones esp. if the beds
are horizontal and well-defined. It is not often used in highly abrasive
igneous rocks because of the cost of drilling. Fraenkel
The Engineering News formula for calculating the load-bearing capacity of
driven piles. Hammond
A graphic record of the measured or computed physical characteristics of
the rock section encountered in a well, plotted as a continuous function
of depth. Measurements are made by a sonde as it is withdrawn from the
borehole by a wire line. Several measurements are usually made
simultaneously, and the resulting curves are displayed side by side on a
common depth scale. Both the full display and the individual curves are
called logs. Well logs are commonly referred to by generic type, such as
resistivity log and radioactivity log, or by specific curve type, such as
sonic log and gamma-ray log. See also:borehole log; sample log;
driller's log. Syn:borehole survey; geophysical log; wire-line log.
AGI
a. A widely used geophysical technique that involves probing of the Earth
with instruments lowered into boreholes, their readings being recorded at
the surface. Among rock properties currently being logged are electrical
resistivity, self-potential, gamma-ray generation (both natural and in
response to neutron bombardment), density, magnetic susceptibility, and
acoustic velocity. Dobrin
b. In deep bores, measurement of resistivity of the formations drilled
through. Electrodes are plunged into the drilling mud at controlled
spacings. See also:electric log
c. The lowering of sensors into a borehole and recording of physical
information as a function of depth. Numerous types of geophysical logs can
be recorded, the more common being rate of penetration, temperature,
gamma-ray, electric, and caliper (for hole diameter). Nelson
A hollow vertical tube, rod, or pipe terminating in a perforated pointed
shoe and fitted with a fine-mesh wire screen; connected with others in
parallel to a drainage pump; driven into or beside an excavation to remove
underground water, to lower the water level and thereby minimize flooding
during construction, or to improve stability. AGI
A centrifugal pump that can handle considerable quantities of air; used
for removing underground water to dry up an excavation. Nichols, 1
Special type of seismometer that is used when recording in a borehole.
Schieferdecker
In seismic work, a method or methods of logging a well so that average
velocities, continuous velocities, or interval velocities are obtained by
lowering geophones into the hole. Shots are usually fired from surface
shot holes, but may be fired in the well itself, or perforating-gun
detonations may be used. In continuous logging, a sound source is lowered
in the hole together with recording geophones. AGI
As used by geologists, it applies to material composed of grains of
approx. uniform size. As used by engineers, it applies to material
containing approx. equal amounts of several grain sizes. Stokes
A tube or tubing used to line wells. Standard, 2
A strainer on a driven well tube to keep out grit. Standard, 2
A point at the end of a perforated tube used for sinking wells.
Standard, 2