Environmental Engineering Reference
In-Depth Information
Kame terrace
A valley-side bench of glaciofluvial sediment marking the course of an
ice-marginal meltwater stream.
Kaolinite
A 1:1 type of clay mineral of high stability but little reactivity, composed of a
silica sheet fused with one alumina sheet.
Karst geomorphology
A landsystem uniquely developed on carbonate rocks by the
predominance of solution and the progressive development of underground drainage.
Katabat
The outflowing, descending portion of a local thermal circulation system during
the cooling phase of diurnal heating in a mountainous region, or any other more
general cold air drainage current.
Katamorphism
Intense and rapid
weathering
of rocks by hydrolysis, hydration and
oxidation under humid tropical conditions.
Kind
A property of soil structure referring to the shape of the aggregates.
Kinetic energy
The energy possessed by a body because of its movement. Its magnitude
is equal to 1/2
mv
2
, where
m
is the mass of the body and
v
is its velocity.
Klippe
A fragment of a
nappe
dispersed away from its source into the mass of a collision
orogen
.
Knick point
A step in the long profile of a stream marking the rejuvenation of fluvial
incision after uplift.
Knock
-
and
-
lochan
A highly abraded, rocky land surface characterized by streamlined
ridges and intervening basins, usually of glacial origin.
Krummholz
A woodland of dwarf trees marginal to the
timberline
, whose individuals
are severely stunted by cold and wind pruning.
Kuroshio
The warm, north-east-flowing current of the clockwise
gyre
in the north
Pacific Ocean, flowing from the Philippine coast and deflected southwards in the
eastern Pacific by the Alaskan coast.
Laccolith
A lens-shaped igneous rock body of moderate size (10
3-4
m long and 10
1-2
m
thick) formed by accordant (
sill
-like)
intrusion
into existing rocks.
Lag deposit
A residual accumulation of coarse rock fragments, too large to move in a
particular force field, after the removal of fines.
Lag gravel
A surface layer of loose, coarse granular debris left after the deflation or
surface wash of fines.
Lag time
The time lapse between a stimulus and its effect such as that between the peak
of a precipitation event and the
peak discharge
response of a stream.
Lahar
A volcanic mudflow of liquefied volcanic and other debris, exacerbated by the
melt and disruption of summit glaciers or crater lakes.
Laminar flow
Fluid flow in which the direction of each individual flow strand remains
discrete and unidirectional, although strands may shear past each other as the channel
walls are approached.
Lapilli
Unconsolidated coarse-grained
pyroclastic
material 2-64 mm in diameter, ejected
into the atmosphere by volcanic eruption.
Latent heat
The quantity of heat absorbed or emitted during a change of state of a
substance. In climatology it usually refers to the change of state of water from solid to
liquid to vapour or vice versa.
Lateral convection
Convectional processes in the oceans brought about by horizontal
differences in density.
