A relict that is unstable under newly imposed conditions of metamorphism,
but persists in a perhaps altered but still recognizable form owing to the
low velocity of transformation. A preferable term would be metastable
relict. CF:stable relict
Not formed or deposited in strata; specif. said of massive rocks or
sediments with an absence of layering, such as granite or glacial till.
AGI
Pumping or draining the water from mines. CF:dewatering
See:fresh
a. The opening in a mine through which the return air ascends and is
removed. Ant: downcast; intake. See also:air shaft
b. An upward current of air passing through a shaft, or the like.
c. Material that has been thrown up, such as by digging.
Webster 3rd
d. Same as upthrow, such as the upcast side of a fault; opposite of
downthrow or downcast. Standard, 2
e. The lifting of a seam or bed by a dike. Syn:uptake
a. A shaft through which air leaves the mine. BS, 8
b. The shaft up which the ventilating current of air returns to the
surface or to the fan. The term corresponds to main return or return drift
in drift mining. Also called fan shaft. Syn:uptake
See also:downcast shaft
See:coning
a. To increase the commercial value of a coal by appropriate treatment.
BS, 5
b. To increase the quality rating of diamonds beyond or above the rating
implied by their particular classification. Long
c. To increase the quality of grades.
See:aggradation
Any shaker conveyor that is so designed as to have the proper stroke for
shaking the maximum amount of coal up a grade. On certain types of shaker
conveyors, this requires the replacement of certain parts of the drive to
secure the desired stroke, rather than replacing the entire drive unit.
Jones, 1
a. A borehole collared in an underground working place and drilled in a
direction pointed above the horizontal plane of the drill-machine swivel
head. Long
b. A shothole drilled in rock at an upward angle. Pryor, 3
In seismic exploration, the setting off of successive shots in a shothole
at varying depths to determine velocities and velocity variation of the
materials forming the walls of the hole. AGI
Used to denote the observed travel time of a seismic wave from the point
of generation at a given depth in a shothole to a detector at the surface;
the observed time equivalent of the corresponding shot depth.
Syn:time at shot point
a. Any force that tends to raise an engineering structure and its
foundation relative to its surroundings. It may be caused by pressure of
subjacent ground, surface water, expansive soil under the base of the
structure, or lateral forces such as wind. AGI
b. A structurally high area in the crust, produced by positive movements
that raise or upthrust the rocks, as in a dome or arch. CF:depression
AGI
Designating a method of shaft excavation by drifting to a point below and
then raising. Webster 2nd
a. Pertaining to rocks or strata that are normally above those of earlier
formations of the same subdivision of rocks. The adjective is applied to
the name of a chronostratigraphic unit (system, series, stage) to indicate
position in the geologic column and corresponds to late as applied to the
name of the equivalent geologic-time unit; e.g., rocks of the Upper
Jurassic System were formed during the Late Jurassic Period. The initial
letter of the term is capitalized to indicate a formal subdivision (e.g.,
"Upper Devonian") and is lowercased to indicate an informal subdivision
(e.g., "upper Miocene"). The informal term may be used where there is no
formal subdivision of a system or series (counterpart of lower).
CF:lower; middle. AGI
b. See:up hole
The part of the Carboniferous strata of the Appalachian field that is now
assigned to the Dunkard group of the Permian series. Obsolete. Fay
The upper bend of a terrace or monocline. Also called head.
upper explosive limit of flammability
The highest quantity of combustible gases that, when mixed with a given
quantity of air (or oxygen), will just support a self-propagating flame.
Francis, 2
Upper Productive Coal Measures
The part of the Carboniferous strata of the Appalachian field that is now
assigned to the Monongahela group of the Pennsylvanian series. Obsolete.
Fay
An auxiliary shaft, a mill hole, carried from one level up toward another.
See also:rise; raise. (These are better terms.) Fay