GLOSSARY
Alluvium -- materials transported and
deposited by the movement of water. Generally not used
to describe sediments in lakes and seas.
Amphibole - a mineral group composed
of varying amounts of magnesium, iron, aluminum (Al),
calcium and sodium in a (SiAl4)O11(OH)2 base.
Arkose -- sedimentary rock composed
of eroded igneous rock of granular texture that has
been cemented together.
Basalt -- an extrusive (reaches the
surface to cool) rock of volcanic origin. It is fine
grained, dark colored igneous rock composed primarily
of calcic (calcium) plagioclase pyroxene.
Brackish -- referring to conditions
where salts range from 1 part per thousand (ppt) to
about 18 ppt; between fresh and salt water
Channelization -- using bulkheads,
armor or other engineering practices to maintain a channel
in a river or harbor in one specific position. Eliminates
natural meandering processes.
Chloride -- an atom of salt that can
be used to determine saline conditions in water and
soils.
Conglomerate -- a naturally occurring
sedimentary rock made by the cementing of pebbles, gravel
and/or sands.
Diabase -- an igneous rock of basaltic
composition characterized by an ophitic structure.
Fault line -- a fracture line or zone
that reaches the surface where there has been parallel
displacement along the fracture due to tectonic activity.
Fault line scarp -- a fault line that
has been acted on by the processes of erosion. Change
is due to erosion rather than direct tectonic activity.
Fetch (some referred to as fetch length)
-- distance that wind can travel uninterrupted over
water in a single direction. The longer the fetch, the
greater the potential for waves.
Floodplain -- area along a river or
stream that regularly floods. Much of the sediment is
derived from the river itself (fluvial)
Floodway -- a term similar to floodplain
although has been used to denote the path of floodwaters
particularly when the floodplain has been developed
and is no longer evident.
Fluvial -- of or pertaining to rivers.
Fragipan (or Hardpan) -- a hard impervious
layer typically made from the downward translocation
of clays in soil profiles. Water movement vertically
across such a barrier is limited.
Freshwater -- water with less than
1 ppt of salt. Does not denote water quality.
Friable -- a term for soil structure
that denotes a poorly compacted soil that crumbles easily
due to partially decomposed organic matter.
Glacial erratic -- large boulders and
rocks carried across the landscape by ice. Some of this
material could have it source hundreds of miles away.
Glacial outwash -- material deposited
on the landscape and redistributed as the glacier melts
and recedes.
Glacial till -- see Till.
Gneiss -- a course-grained layered
rock that alternates between granular minerals and schistose
minerals.
Granite -- an igneous rock that consists
of feldspar and quartz.
Hornblende -- a type of amphibole.
Hydrograph -- a graphic representation
of water flows through a basin showing stage, flow,
velocity and other properties of water with respect
to time.
Igneous rock -- rock of volcanic origin
that forms from the cooling of magma. Includes basalts.
Inland wetland -- all non-tidal wetlands
and watercourses of the State of Connecticut.
Loam -- a soil composed of sand, silt,
clay and organic material. Typically the upper soil
layers that best support growing plants (generically
termed topspoil).
Metamorphic rock -- rock composed of
sedimentary and igneous rocks that have been altered
by temperature, pressure and chemistry. Includes gneiss
and schist rocks.
Mica -- a mineral group composed of
phyllosilicates (varying amounts of potassium, sodium,
calcium, iron, magnesium, aluminum in Si4O10 base) with
sheet-like structure and characterized by almost perfect
basal cleavage.
Non-point source pollution -- pollution
that does not come from a single outlet source. Lawn
fertilizer traveling down a storm drain is a classic
example.
Ophitic -- a term that is applied to
texture of a diabase where hedral-shaped crystals are
imbedded in a base of augite (a rock in the mineral
group pyroxene)
Panne -- a small depression on a marsh
that accumulates salts as sea water evaporates. The
increase in salinity and reductions in oxygen combine
to change the vegetation that can colonize these areas.
Peat -- a type of substrate that is
dominated by partially decomposed organic matter accumulating
in wet places.
Pedon -- the soil "footprint" is a
term that refers to the layering of the soil. As soils
mature and new soils are deposited, the soil layers
take on distinct characteristics in layers that can
be used to identify soil types. Young or disturbed soils
have fewer pedons.
Plagioclase -- a mineral group composed
of varying amounts of sodium, calcium, aluminum and
silica (Si) in a Si2O8 base. One of the most common
rock-forming mineral types.
Point source pollution -- pollution
from a single identifiable source. An outfall pipe from
a factory is a classic example.
Potable -- water (or liquid) suitable
for human consumption.
Pyroxene -- a mineral group composed
of varying amounts of calcium, magnesium, iron, and
aluminum in a silica oxide (Si2O6) base
Saltwater -- water with salts at or
near the strength of sea water and generally above18
parts per thousand, but more typically about 25 ppt.
Sandstone -- a sedimentary rock composed
of sands. This rock is erode relatively easily.
Schist -- a metamorphic rock with a
foliated structure split up in thin irregular plates.
Can range in particle size from clay (shale) to more
coarse-grained rocks, the latter typically containing
parallel orientation of micaceous (mica) minerals.
Sea level rise -- the relative increase
in water levels along the coast. Includes the addition
of meltwater and increases in ocean volume due to temperature
changes relative to changes in position and elevation
of landmasses.
Secondary growth forest -- a reforested
site that has repeatedly been denuded of trees. Typically
refers to areas that have been farmed in the past and
is now recovering a woody habitat. Plant community structure
is often changed forever.
Sedimentary rock -- rock formed from
the erosion, deposition and compaction of soil types
(clay and silt - shale or mudstones; sand -- sandstone,
arkose).
Shale -- a sedimentary rock formed
from the accumulation of clays and silts and lain down
in thin regular plates.
Tidal -- of or pertaining to tides.
In Branford these occur once every 12 hours 54 minutes
and are defined by spring (highest and lowest) and neap
(mid) tides every two weeks.
Tidal range -- The average difference
between high tide and low tide.
Till -- a stiff clay full of stones
of varying size. Is used today to denote non-sorted
clays, silts and sands carried by glaciers and deposited
on the landscape during retreat (glacial till).
Trap rock -- a common name given to
rock of volcanic origin that is often mined for construction
projects (e.g., road bedding). It typically includes
basalt and/or diabase
Tributary -- a branch of a large river
Udorthents -- soils that have been
disturbed by human activity. They are typically mixed
soils imported or amended for construction activities.
They are young and do not exhibit many of the pedons
associated with natural soil profiles.
Understory -- refers to the plant community
that typically lives under the canopy of trees.
Vernal pool -- an area that is wet
only part of the year, typically during the spring season.
It is an important habitat for reproduction in many
reptiles and amphibians.
Water -- refers to both aquatic and
marine resources. The following designations are used
to denote differences in marine resources. Colors noted
below are a general classification and does not denote
water quality or actual color, rather, it is used by
coastal scientists to delineate a general area within
the marine environment.
Blue-water -- denotes deeper waters of the Long Island
Sound
Gray-water -- denotes shallow waters of the Long Island
Sound, harbors and bays
Brown-water -- denotes waters in the rivers, estuaries
and marshes.
Watershed -- the area that encompasses
a stream or river that drains into it and supplies its
water. It is usually defined by topography.
Water quality -- denotes the amount
of chemicals, pollutants and nutrients in water above
natural levels.
Wave action -- energy caused by the
movement of waves against the shore. It depends of wind
speed, fetch and direction and is often used as a way
of determining the potential for erosion.
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