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endomorph

A crystal surrounded by another crystal of a different mineral species.
Adj. endomorphic, endomorphous.

endomorphic

Pertaining to contact metamorphism that takes place within the cooling
intrusive rock; resulting from the reaction of the wall rock upon the
peripheral portion of an intrusion.

endomorphic metamorphism

See:endomorphism

endomorphism

Changes within an igneous rock produced by the complete or partial
assimilation of country-rock fragments or by reaction upon it by the
country rock along the contact surfaces. It is a form of contact
metamorphism with emphasis on changes produced within the igneous body
rather than in the country rock. The term was originated by Fournet in
1867. CF:exomorphism
Syn:endometamorphism; endomorphic metamorphism. AGI

end-on

Working a seam of coal, etc., at right angles to the cleat, or natural
planes of cleavage. Fay

end-on working

Working of coal seam at right angles to the natural cleats, joints, or
slips. Pryor, 3

endoscope

In gemology, an instrument that affords a magnified image of the drill
hole of a pearl, used to distinguish between genuine and cultured pearl. A
tiny beam of light is directed into the walls of the drill hole to reveal
whether the structure of the pearl's core is concentric (genuine) or
parallel (cultured).

endostratic formation

Bedding in clays resulting from alternating, desiccation, and saturation
by groundwater. Hess

endothermic

Accompanied by the absorption of heat. Opposite of exothermic. CTD

endplate

In timbering, where both a cap and a sill are used, and posts act as
dividers, the posts become the endplates. See:sideplate

end-port furnace

A furnace with ports for fuel and air in the end wall. ASTM

ends

York. Headings driven on the end or end-on. Fay

end slicing

See:top slicing combined with ore caving

end span

A span that is a slab or a continuous beam at its interior support.
Hammond

endurance

The ability of a metal or a fabricated structure to recover from or to
withstand repeated stress loadings or fluctuations. Pryor, 3

endurance limit

That stress below which a material can withstand hundreds of millions of
repetitions of stress without fracturing. It is considerably lower than
rupture strength. Syn:fatigue limit

endwall

a. The brick, concrete, or stonework construction at the sides of an
excavation built to carry a flat or arched roof. Also called sidewall.
Spalding
b. The vertical refractory wall, farthest from the furnace chamber, of the
downtake of an open-hearth steel furnace. Dodd
c. One of the two vertical walls terminating a battery of coke ovens or a
bench of gas retorts; it is generally constructed of refractory bricks and
heat-insulating bricks with an exterior facing of building bricks.
Dodd

en echelon

Said of geologic features that are in an overlapping or staggered
arrangement, e.g., faults. Each is relatively short, but collectively they
form a linear zone, in which the strike of the individual features is
oblique to that of the zone as a whole. Etymol: French en echelon, in
steplike arrangement. AGI

enelectrite

Minute, colorless, monoclinic, lath-shaped crystals, presumably a
hydrocarbon; found in chemawinite (variety of amber), Cedar Lake, MB,
Canada. Tomkeieff

energizing coil

Primary coil that is used in inductive methods to set up electric currents
in the Earth. Schieferdecker

energy

a. The ability of a body to perform work. Shell
b. The capacity for producing motion. Energy holds matter together. It can
become mass, or it can be derived from mass. It takes such forms as
kinetic, potential, heat, chemical, electrical, and atomic energy, and it
can be changed from one of these forms to another. Leet, 1
c. Kinetic energy is that due to motion, and potential energy is that due
to position. In a stream, for example, the total energy at any section is
represented by the sum of its potential and kinetic energies.
Seelye, 1