A sedimentary rock composed of relatively coarse sand grains in a very
fine silt or clay matrix. AGI
See:stercorite
Said of the texture of a rock consisting of or having crystals that are
small enough to be visible only under the microscope; also, said of a rock
with such a texture. Syn:cryptocrystalline; micromeritic. AGI
See:trace element
Those characteristic and distinctive aspects of a sedimentary rock that
are visible and identifiable only under the microscope (low-power
magnification). AGI
A unit of capacitance; one-millionth of a farad; symbol, mu F.
Crispin
Having a microscopic flow texture. Standard, 2
a. The study of the microscopic features of rocks.
b. The study of the relationships of microorganisms to geologic and
geochemical processes.
Having a microscopic granitoid structure. Standard, 2
a. Said of the texture of a microcrystalline, xenomorphic igneous rock.
Also, said of a rock with such a texture. AGI
b. Minutely granular; specif. said of the texture of a carbonate
sedimentary rock wherein the particles are mostly 10 to 60 mu m in
diameter and are well-sorted, and the finer clay-sized matrix is absent.
Also said of a sedimentary rock with such a texture. AGI
A graphic reproduction of a magnified object as seen through a microscope.
When it is a photograph, it is called a photomicrograph. Stokes
Said of the graphic texture of an igneous rock that is distinguishable
only with the aid of a microscope; also, said of a rock having such
texture. AGI
The hardness of microscopic areas or of the individual microconstituents
in a metal, as measured by means such as the Tukon, Knoop, or scratch
methods. ASM, 1
One microhm equals 10-6 Omega , which equals 103
electromagnetic units. Symbol, mu Omega . Webster 2nd
Microite is found in many coals and occurs in large quantities in Gondwana
coals and in Permocarboniferous coals of the former U.S.S.R. It is most
abundant in coals with little exinite, or coals of high rank in which
exinite cannot be recognized, and may occur in very persistent thick
bands. It is present in small amounts in Carboniferous coals of the
Northern Hemisphere. IHCP
A well log obtained with an arrangement of electrodes similar to a
miniature laterolog but disposed in concentric fashion in an insulating
pad. The current from a central electrode is focused and flows out in a
pattern that resembles the shape of a trumpet. As in the microlog, the
electrodes are mounted on a pad that is held against the wall of the hole
by springs. The microlaterolog serves a purpose similar to that of a
microlog, investigating only a small volume of rock immediately adjacent
to the hole. Syn:trumpet log
a. A microscopic crystal that polarizes light and has some determinable
optical properties. CF:crystallite; crystalloid. Syn:microlith
AGI
b. A pale-yellow, reddish, brown, or black isometric mineral of the
pyrochlore group: (Ca,Na)2 Ta2 O6 (O,OH,F). It is
isomorphous with pyrochlore, and it often contains small amounts of other
elements (including uranium and titanium). Microlite occurs in granitic
pegmatites and in pegmatites related to alkalic igneous rocks, and it
constitutes an ore of tantalum. Syn:djalmaite
See:microlite
A typical association of macerals in coals, occurring in bands at least 50
mu m wide. Microlithotype names bear the suffix "-ite".
See also:lithotype