Geological Features of Northwest Connecticut

The northwest corner /marble valley of Connecticut is part of the proto –North American tectonic plate

The most characteristic feature of the Northwest Highlands is their high, steep-sided plateaus.

The plateaus formed by weather/erosion resistant bedrock than the valleys below.

The plateaus consist of tough schists and granites.

The valleys are sunk into marble, metamorphic rock that is not resistant to weathering and erosion in Connecticut’s climate.

Formation

Bear Mountain

Formation of marble Marble is

metamorphosed from limestone, a sedimentary rock composed mostly of carbonate mud and the shell fragments of marine fossils.

The lime-rich minerals that make up shells and carbonate mud weather quite easily. (Seashells left outside rapidly take on a dulled appearance for the same reason.) (Bell 2009)

Formation cont.Pre-Historic Coral reef

Pre-Historic Marine Life

Formation cont.

Connecticut Pre-Historic Shoreline

Formation of marble valleyMarble is readily

dissolved by the slight acidity of natural rainwater, forming deep lowlands between the high plateaus of the Northwest Highlands.

The Housatonic River flows through the valley and drains into Long Island Sound

The lowlands of the northwest corner is referred to as the marble valley (Bell 20o9)

Formation cont.

Housatonic River

Marble is metamorphic rock of limestone

Formation cont.

Marble Valley

Kent Falls State Park

LocationKent Falls is located in the town of Kent in the

northwest section of Connecticut near the New York State border

Kent Falls State park

Scatacook Native Americans named the area Settled the area and

fished the watersFalls Brook forms a series

of waterfalls that result in over 70 feet of cascades

Consists of 295 acresDeveloped in the 1930’s

by the Civil Works Administration (CWA)

1970’s hiking trails are developed by the Youth Conservation Corps of Connecticut

Kent Falls state park Information

The most outstanding feature at Kent Falls is, of course, the falls

Made of a series of falls and cascades that generally form where the bedrock contains alternating hard and soft layers.

This part of Connecticut was once made of coral reefs, offshore from the northwestern part of the state.

Why Kent Falls State Park?Approximate location of Connecticut

The corals made of limestone metamorphosed under extreme pressure from the colliding tectonics plates into marble

The easily weathered/eroded marble wears away at a faster rate causing a drop in elevation (CT D.E.P. 2009)

Why Kent Falls State Park cont.?

Eroded marble potholes from swirling pebbles in water

Exposed marble at bottom of valley

Sight seeing

Recreation

Kent Falls covered bridge

Recreation cont.Hiking

Recreation cont.

Scenic overlook

Recreation cont.

Picnicking

Enjoying the cool water

http://www.ct.gov/Dep/cwp/view.asp?a=2716&q=325228&depNav_GID=1650 (2009)

http://www.tmsc.org/face_of_ct/index.html (2009)

Work cited

Write one paragraph describing how the marble valley of Northwest Connecticut was formed.

Assessment