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 (sometimes 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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