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flowage structure

See:flow structure

flow banding

A structure of igneous rocks that is esp. common in silicic lava flows. It
results from movement or flow, and is an alternation of mineralogically
unlike layers.

flow breccia

A breccia that is formed contemporaneously with the movement of a lava
flow; the cooling crust becomes fragmented while the flow is still in
motion. AGI

flow characteristic

The rate at which a metal powder will flow through an orifice in a
standard instrument, and/or according to a specified procedure.
Rolfe

flow cleavage

A syn. of slaty cleavage, so called because of the assumption that
recrystallization of the platy minerals is accompanied by rock flowage.
CF:fracture cleavage

flower of iron

See:flos ferri

flowers of sulfur

A light-yellow, pulverulent modification of sulfur formed when sulfur
vapor is condensed. Standard, 2

flow folding

Folding in incompetent beds that offer so little resistance to deformation
that they assume any shape impressed upon them by the more rigid rocks
surrounding them or by the general stress pattern of the deformed zone.
CF:ptygmatic folding

flow gneiss

A gneiss with a structure produced by flowage in an igneous mass before
complete solidification.

flow gradient

A drainageway slope determined by the evelation and distance of the inlet
and outlet, and by required volume and velocity. Nichols, 1

flowing film concentration

In metallurgy, a concentration based on the fact that liquid films in
laminar flow possess a velocity that is not the same in all depths of the
film. There is no flow at the bottom but maximum at or very near the top
resulting from the internal friction of one layer upon another. By this
principle, lighter particles are washed off while the heavier particles
accumulate and are intermittently removed. This is basis of the stationary
table, which has been known for thousands of years. Vanners and round
tables have been developed from this basic principle, whereas bumping and
shaking tables jointly utilize flowing film and other principles.
Gaudin, 1

flow layer

An igneous-rock layer, differing mineralogically or structurally from the
adjacent layers, which was produced by flowage before the complete
solidification of the magma. CF:flow line; schlieren.

flow line

A lineation of crystals, mineral streaks, or inclusions in an igneous
rock, indicating the direction of flow before consolidation.
CF:flow layer

flowmeter

a. A device installed in a drilling-fluid circulation system that
registers the number of gallons (liters) of liquid circulated per minute
and also indicates when the flow past the bit ceases. Long
b. A device which registers rate of flow, and perhaps quantity, of gases,
liquids, and fluid pulps. Used in mineral dressing to measure rates and
quantities of pregnant solutions in cyanide and to control liquid
additions to pulps. Pryor, 3

flow rate

Weight of dry air flowing per unit time. Measured in kilograms per second.
Hartman, 2

flow roll

A rounded, pillowlike body or mass of sandstone occurring within or just
above finer-grained sediment or commonly within the basal part of a
sandstone overlying shale or mudstone. Its shape approaches that of an
elongate, flattened ellipsoid (short axis more or less vertical), and is
presumed to have formed by deformation, such as by large-scale load
casting or mud flowage accompanied by subaqueous slump or foundering of
sand channels. AGI

flowsheet

A diagram showing the progress of material through a preparation or
treatment plant. It shows the crushing, screening, cleaning, or refining
processes to which the material is subjected from the run-of-mine state to
the clean and sized products. The size range at the various stages may
also be shown. Nelson

flow stretching

The orientation and possible deformation of crystals with their long axes
in the direction of plastic flow in metamorphic rocks.

flow structure

a. A structure of igneous rocks, generally but not necessarily volcanic
rocks, in which the stream lines or flow lines of the magma are revealed
(1) by alternating bands or layers of differing composition,
crystallinity, or texture, or (2) by subparallel arrangement of prismatic
or tabular crystals. Syn:flow texture; fluidal structure;
fluxion structure.
b. A primary sedimentary structure resulting from subaqueous slump or
flow. AGI

flow texture

See:flow structure; fluidal texture.

flow unit

One of the nearly contemporaneous subdivisions of a lava flow (usually
basaltic) that consists of two or more parts that were poured one over the
other during the course of a single eruption.