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pedimentation

The process of pediment formation.

pediment pass

A narrow, flat, rock-floored tongue extending upslope from the main
pediment and penetrating a mountain sufficiently to meet another pediment
slope extending into the mountain from the other side.

pedion

A crystal form consisting of a single crystal face.

pediplane

Broad, rock-cut, thinly alluviated surface formed by the coalescence of
adjacent pediments and desert domes.

pedis possessio

The actual possession of a piece of mineral land to the extent needed to
give the locator room to work and to prevent probable breaches of the
peace, but not necessarily to the extent of a mining claim.

pedocal

Soil enriched in calcium carbonate, accumulating in regions of low
temperature, low rainfall, and prairie vegetation. CF:pedalfer

pedogenesis

The formation of soil from parent material.

pedogeochemical prospecting

Synonymous with geochemical soil survey. Hawkes, 1

pedologic horizon

See:soil horizon

pedology

The science that treats soils, their origin, character, and utilization.
AGI

pedometer

A pocket-size instrument that registers the number of steps taken by the
person carrying it. AGI

pedosphere

The part of the Earth in which soil-forming processes occur.

peeler

a. One of a set of blades that picks up and channels water moved outward
by the impeller of a centrifugal pump. Nichols, 1
b. An iron implement with a flattened end and ring handle, which is used
by a baller in placing blooms, ingots, etc., in a reheating furnace.
Standard, 2
c. See:calk

Peerless explosive

High explosive; used in mines. Bennett

peg

a. A surveyor's mark.
b. To mark out a miner's claim at the four corners by pegs bearing the
claimant's name. Sometimes used as "peg out." Webster 3rd; Fay

peg adjustment

The adjustment of a spirit-leveling instrument of the dumpy-level type in
which the line of collimation is made parallel with the axis of the spirit
level by means of two stable marks (pegs) the length of one instrument
sight apart. AGI

pegleg

An abrupt change or sharp bend in the course of a borehole. Also called
dogleg. Long

pegmatite

An exceptionally coarse-grained igneous rock, with interlocking crystals,
usually found as irregular dikes, lenses, or veins, esp. at the margins of
batholiths. Most grains are 1 cm or more in diameter. Although pegmatites
having gross compositions similar to other rock types are known, their
composition is generally that of granite; the composition may be simple or
complex and may include rare minerals rich in such elements as lithium,
boron, fluorine, niobium, tantalum, uranium, and rare earths. Pegmatites
represent the last and most hydrous portion of a magma to crystallize and
hence contain high concentrations of minerals present only in trace
amounts in granitic rocks. Adj: pegmatitic. Syn:giant granite
CF:symplectite

pegmatitic

a. Said of the texture of an exceptionally coarsely crystalline igneous
rock. AGI
b. Occurring in, pertaining to, or composed of pegmatite.
Syn:pegmatoid

pegmatitic stage

a. A final stage in the normal sequence of crystallization of a magma at
which the residual fluid is sufficiently enriched in volatile materials to
permit the formation of coarse-grained rocks (pegmatite) more or less
equivalent in composition to the parent rock. CF:orthomagmatic stage
AGI
b. The late stages of magma crystallization in S-type, 2-mica granites.

pegmatitization

The process of formation of, introduction of, or replacement by pegmatite.