A
Alluvial	sediments of gravel, sand, silt or clay deposited by water.
B
Bird's foot delta	triangular deposit of fine sediment at the mouth of a large river.
C
Cobble	a water rounded stone.
D
Delta	low, nearly flat body of sediment deposited when the flow of a river is slowed as it enters a lake or ocean.
Diabase	a medium grained mafic volcanic rock.
Dike	a volcanic intrusive rock perpendicular to dominant stratigraphy.
Drumlin	an elongated hill formed by glacial till material deposited in the direction of the glacier that formed it.
Dune Complex	finely grained sandy landscape feature often on a shoreline, formed by wind.
E
Erratic	a large rock deposited by a glacier.
Esker	an elongated ridge deposited by meltwater in a glacial channel.
F
Fen	a wet peatland with moderate pH, influenced by groundwater, where characteristic plants are sedges, willows, larch and aquatic mosses.
Fluvial	Fluvial - formed by the action of flowing water.
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G
Gabbro	a course-textured igneous rock.
Glacial	climatic zone that produced continuous ice up to .3 km thick, shaping landscapes as early as 2.7 billion years ago.
Ground Moraine	till deposited beneath a glacier.
Gunflint Formation	a geological formation primarily comprised of iron rich sediments with some volcanics, occurring from Michigan to Thunder Bay, formed prior to 1.1 billion years ago and used as a source for tool making material.
H
ha	abbreviation for hectare - 100 by 100 metres square (approx. 2.5 acres).
Hibernaculum	shelter of a hibernating animal.
K
Kame	a terrace-like accumulation of sand or gravel deposited at or near the end of a glacier by meltwater streams.
Kettle	hole formed from melting buried ice blocks in glacial deposits.
Krumholz Effect	stunted growth of trees caused by extreme climatic conditions.
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L
Lucustrine	sediments deposited during the late glacial and early postglacial period as silt and clay.
M
Marsh	an area of low wet land which is covered by grasses.
Mesa	a butte; a flat-topped erosional feature, with diabase caps in the Lakehead region.
Metasedimentary	Metasedimentary - sedimentary rock that has been changed by heat or pressure.
Moraine	a surface deposit of gravels forming usually sinuous double sided ridges; denotes the former outer edges of ice sheets.
O
Osler Group	dominated by a sequence of basaltic lava flows and located along Black Bay penisula extending from Edward Island west to Copper Island east.
Outwash Plain	flood plain formed by streams drawing from the front of a glacier.
Oxbow Lake	lake formed when a u-shaped bend or "meander" is cut off from a river channel.
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P
Precambrian	all time prior to 570 million years ago.
Proterozoic	a time period roughly 2.7 billion to 570 million years ago.
R
Raised Beach	a stranded former lake shore.
River Terrace	remnants of flood plain formed when a river cuts through sediments. Renewed water flow will produce another terrace below the level of the previous one.
Rove Formation	series of sedimentary rock deposited in the mid Proterozoic; this slate material underlays a significant portion of the diabase caps of the NorÕWesters.
Rossport Formation	late Precambrian sedimentary rock deposited as mudstone north of Lake Superior.
S
Sandspit	long, narrow sandbar created by current flowing past a point of land that protrudes from the main land.
Sedimentary	rocks formed when igneous rocks are eroded and laid down as sediment under a sea (shale, sandstone).
Sedimentary rock	layered mounds of rock formed mainly of material deposited by water, wind or ice.
Sibley Group	extends from the Sibley penisula in the west to the Channel Islands in the east and contains red sandstone with irregular banding (1.4 to 1.3 billion years old) .
Sill	a volcanic intrusive rock formed parallel to the dominant statigraphy.
Spillway	channel for reservoir overflow.
Stromatolite	Precambrian fossils formed by mats or clumps of algae that trapped sediment.
T
Talus	an accumulation of large rock fragments resting at the base of a cliff or steep slope.
Terminal Moraine	long ridge or hill produced by concentrated glacial deposition along the margin of a glacier.
Till	rock material released from a moving glacier.
V
Volcanic	a rock crystalized from molten lava.

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