a. A marine sedimentary facies characterized by a thick sequence of poorly
fossiliferous, thinly bedded, graded deposits composed chiefly of marls,
sandy and calcareous shales, and muds, rhythmically interbedded with
conglomerates, coarse sandstones, and graywackes. AGI
b. An extensive, preorogenic sedimentary formation representing the
totality of the facies deposited in different troughs, by rapid erosion of
an adjacent and rising mountain belt at a time directly previous to the
main paroxysmal (diastrophic) phase of the orogeny; specif., the Flysch
strata of late Cretaceous to Oligocene age along the borders of the Alps,
deposited before the main phase (Miocene) of the Alpine orogeny.
AGI
c. A term that has been loosely applied to any sediment with most of the
lithologic and stratigraphic characteristics of a flysch, such as almost
any turbidite. Ethymol. dialectal term of German origin used in
Switzerland for a crumbly or fissile material that slides or flows.
CF:molasse
A heavy wheel used in a rotating system to reduce surges of power input or
demand by storing and releasing kinetic energy as it changes its rate of
rotation. Pryor, 3
A method of dust suppression in which thick foam is forced through the
drill by means of compressed air and the foam and dust mixture emerges
from the mouth of the hole in the form of a thick sludge. With this method
the amount of dust dispersed into the atmosphere is almost negligible and
the amount of water used is about 1 gal/h (3.8 L/h). Approx. 30 to 50 ft
(9 to 15 m) of drilling can be done with one filling of the unit.
Mason
A material that tends to stabilize a foam. See:frothing agent
ASM, 1
Soft or earthy aphrite. See also:earth foam
The injection of foam into shotholes and connecting breaks to displace any
combustible gases present and to minimize further combustible gases
emission into the shotholes, thereby reducing the risk of ignition of the
gas during shot firing. BS, 12
A secondary method of fighting underground fires, devloped in Great
Britain in 1956. It consists of filling the fire area with soap bubbles
which are moved forward by the air current. The foam is produced by
passing the air current through a cotton net, saturated with a dilute
solution of detergent, which is stretched across the mine roadway. The air
passing through the net forms bubbles 1/2 to 1-1/2 in (1.3 to 3.8 cm) in
diameter which honeycomb and form a plug of foam that tends to quench the
fire and reduce its temperature to a point where it can be attacked
directly and without protective clothing. See also:high-expansion foam
Nelson
See:aphrite
Frothy amber. Almost opaque chalky white amber. Will not take a polish.
See:free on board
An arbitrary reference sphere drawn about the hypocenter or focus of an
earthquake, to which body waves recorded at the Earth's surface are
projected for studies of earthquake mechanisms. AGI
a. The initial rupture point of an earthquake, where strain energy is
first converted to elastic wave energy; the point within the Earth which
is the center of an earthquake. Syn:hypocenter
b. The point at which rays of light converge to form an image after
passing through a lens or optical system or after reflection by a mirror.
AGI
Logging device designed to focus lines of current flow. Wyllie
Eight pigs of cast iron. Webster 2nd
Quenching in a fine vapor or mist. ASM, 1
A term proposed by Johannsen; derived by contracting the word
feldspathoid; used in his classification of igneous rocks to indicate one
of the feldspathoidal group of minerals. CF:feldspathoid
A crack or a break in the roof. CTD
a. A curve or bend of a planar structure such as rock strata, bedding
planes, foliation, or cleavage. A fold is usually a product of
deformation, although its definition is descriptive and not genetic and
may include primary structures. CF:anticline; syncline; monocline.
AGI
b. In crystallography, refers to the number of repetitions about a
crystallographic axis to return to identity; i.e., equal to a complete
rotation of 360 degrees . Modern usage refers to a six-fold axis as a
hexad, a four-fold axis as a tetrad, three-fold as triad, two-fold as
diad, and one-fold as monad.
See:axis
A local tectonic breccia composed of angular fragments resulting from the
sharp folding of thin-bedded, brittle rock layers between which are
incompetent ductile beds; e.g., a breccia formed where interbedded chert
and shale are sharply folded. CF:tectonic breccia
A fault formed in causal connection with folding.