See:datum plane
A selected distant point from which the bearings to other points can be
measured at a survey station. Hammond
See:datum plane
In seismic prospecting, a detector placed to record successive shots under
similar conditions, to permit overall time comparisons. Used in connection
with the shooting of wells for velocity. AGI
Separation size, designated size, or control size used to define analyses
of the products of a sizing operation. BS, 5
Taken or laid down as a standard for measuring, reckoning, or
constructing. Webster 3rd
A station for which tidal constants have previously been determined and
that is used as a standard for the comparison of simultaneous observations
at a second station; also, a station for which independent daily
predictions are given in the tide or current tables from which
corresponding predictions are obtained for other stations by means of
differences or factors. AGI
The process of measuring the horizontal (or slope) distances and
directions from a survey station to nearby landmarks, reference marks, and
other permanent objects that can be used in the recovery or relocation of
the station. AGI
An orthorhombic mineral, C20 H32 O2 ; soft; white; in
modern resins and lignite at Montorio, Abruzzes, Italy. Also spelled
reficite.
a. To free from impurities; to free from dross or alloy; to purify, as
metals; to cleanse. Webster 3rd
b. To treat cast iron in the refinery furnace so as to remove the silicon.
Webster 3rd
Wrought iron made by puddling pig iron. CTD
a. A facility in which relatively crude smelter products such as blister
copper are refined and emerge as acceptably pure products.
b. An electrolytic or chemical facility producing pure metals.
The purification of crude metallic products. Fay
A medium orange heat, about 655 degrees C, which imparts fineness of grain
and toughness to steel that is raised to it and afterwards quenched.
Webster 2nd
A temperature, usually just higher than the transformation range, employed
in the heat treatment of steel to refine the structure, particularly the
grain size. ASM, 1
A compound microscope in which plane-polarized light impinges upon a
polished specimen, commonly opaque, the light being reflected back to the
objective through a second polarizer, where mineral color and polarization
colors are observed in the ocular. Syn:ore microscope
See also:optical constant; polished section; microscopy.
See:ore microscopy
A (gaseous) pressure wave resulting from a direct wave striking an
obstacle or an opposing surface and being reflected backwards.
Rice, 2
a. The return of a wave incident upon a surface to its original medium.
CF:refraction; diffraction; total reflection.
b. The bounding back of light or other rays as they strike a solid
surface. Light incident on a polished planar surface reflects at an angle
equal to the incident angle, the proportion of reflected light increasing
with increasing refractive index; e.g., for normal incidence, 17% reflects
from diamond (n=2.4), and 5% reflects from quartz (n=1.5).
c. In seismic prospecting, the returned energy (in wave form) from a shot
that has been reflected from a velocity discontinuity back to a detector;
the indication on a record of reflected energy.
d. Misnomer for X-ray diffraction peaks. Also spelled reflexion.
An instrument that measures angles between crystal faces by reflecting a
beam of light from successive faces as the crystal is rotated.
See also:contact goniometer
A rule stating that rock breaks from the surface inward toward the
explosive rather than from the explosive charge outward.
Syn:blasting reflection mechanism