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glacial action

All processes due to the agency of glacier ice, such as erosion,
transportation, and deposition. The term sometimes includes the action of
meltwater streams derived from the ice. See also:glacial erosion
AGI

glacial deposits

See:glacial drift

glacial drift

Boulders, till, gravel, sand, or clay transported and deposited by a
glacier or its meltwater. See also:glacial overburden; drift.
Syn:glacial deposits

glacial epoch

Any part of geologic time, from Precambrian onward, in which the climate
was notably cold in both the Northern and Southern Hemispheres, and
widespread glaciers moved toward the equator and covered a much larger
total area than those of the present day; specif. the latest of the
glacial epochs, known as the Pleistocene Epoch. Syn:glacial period;
drift epoch. AGI

glacial erosion

The grinding, scouring, plucking, gouging, grooving, scratching, and
polishing effected by the movement of glacier ice armed with rock
fragments frozen into it, together with the erosive action of meltwater
streams. See also:glacial action

Glacialite

Trade name for a white clay from Enid, OK., marketed as a fuller's earth.
English

glacial overburden

Glacial-drift materials overlying bedrock. See also:glacial drift
Long

glacial period

See:glacial epoch

glacial soil

Soil composed of boulder clays, moraines, etc., which were formed by the
action of ice during the Pleistocene age. Mining

glacial till

See:till

glaciated

Said of a formerly glacier-covered land surface, esp. one that has been
modified by the action of a glacier or an ice sheet, as a glaciated rock
knob. AGI

glaciation

a. The formation, movement, and recession of glaciers or ice sheets.
AGI
b. The covering of large land areas by glaciers or ice sheets. AGI
c. The geographic distribution of glaciers and ice sheets. AGI
d. A collective term for the geologic processes of glacial activity,
including erosion and deposition, and the resulting effects of such action
on the Earth's surface. AGI
e. Any of several minor parts of geologic time during which glaciers were
more extensive than at present; a glacial epoch, or a glacial stage.
AGI

glacier

A large mass of ice formed, at least in part, on land by the compaction
and recrystallization of snow, moving slowly by creep downslope or outward
in all directions due to the stress of its own weight, and surviving from
year to year. Included are small mountain glaciers as well as ice sheets
continental in size, and ice shelves that float on the ocean but are fed
in part by ice formed on land. AGI

glacier theory

The theory, first propounded about 1840 and now universally accepted, that
the drift was deposited through the agency of glaciers and ice sheets
moving slowly from higher to lower latitudes during the Pleistocene Epoch.
AGI

glaciofluvial

Pertaining to the meltwater streams flowing from wasting glacier ice and
esp. to the deposits and landforms produced by such streams, as kame
terraces and outwash plains; relating to the combined action of glaciers
and streams. Syn:fluvioglacial

glaciolacustrine

Pertaining to, derived from, or deposited in glacial lakes; esp. said of
the deposits and landforms composed of suspended material brought by
meltwater streams flowing into lakes bordering the glacier, such as
deltas, kame deltas, and varved sediments. AGI

glaciology

a. The study of all aspects of snow and ice; the science that treats
quantitatively the whole range of processes associated with all forms of
solid existing water. Syn:cryology
b. The study of existing glaciers and ice sheets, and of their physical
properties. This definition is not internationally accepted. AGI

glaciomarine

Of, or relating to, processes or deposits that involve the action of
glaciers and the sea, or the action of glaciers in the sea. Fay

gladite

An orthorhombic mineral, PbCuBi5 S9 ; occurs in soft,
metallic prismatic crystals; sp gr, 6.96; in lead-zinc ores at Gladhammar,
Kalmar, Sweden.

glady

a. A term used in Devon, England, for a variegated black and white clay
having a slippery or smooth texture and often associated with stoneware
clays. Also spelled: gladii. AGI
b. Said of a limestone-outcrop area having shallow soil. AGI

glance

a. A mineral having a splendant luster, e.g., chalcocite (copper glance).
b. Any of several sulfide minerals that are mostly dark colored, having a
metallic luster. Syn:lead sulfide