460 likes | 649 Views
Us???. How did WE form? The earth…continent…US…NY…Long Island…Atlantic Ocean…Long Island Sound. Formation of The Atlantic Coast of North America. Break-up of Pangea (180 mya) Formation of Atlantic Ocean Erosion of Appalachian Mountains. Fig. 1-18, G.
E N D
Us??? • How did WE form? • The earth…continent…US…NY…Long Island…Atlantic Ocean…Long Island Sound
Formation of The Atlantic Coast of North America • Break-up of Pangea (180 mya) • Formation of Atlantic Ocean • Erosion of Appalachian Mountains
PANGEA (the super continent)Formation of The Atlantic Coast of North America • 180 million yrs. ago – all continents were attached together and have slowly moved apart over time • Discovered (S. F. Bacon, 1600’s) “Coasts of continents fit together like a puzzle.” • Lead to theory of continental drift and plate tectonics.
Pangea (reptile fossils) fnft
Formation of Long Island • River erosion carving out the coastal plain to form Long Island Sound Basin (<3 mya) • Glaciers reshaped the area (beginning 3 mya) • The last ice advance (Wisconsinan) ended about 21,000 years ago - deposited terminal moraine in middle of Long Island • Recessional moraines (along North Shore) were left as glacier receded
Formation of Long Island Sound • Glacial Lake Connecticut, which drained (15,000 years ago) • Sea-level rose and ocean entered Long Island Sound Basin • Sea-level rise slowed and marshes began to develop along the margins of the estuary (5,000 - 3,000 years ago) • became what we know as the Long Island Sound
The Formation of Glacial-Marine Sediments Fnft Ice Rafting Glaciers form land and alter sedimentation
Waterbodies of Long Island • East River, Atlantic Ocean • 3 South Shore “Bays:” Great South Bay, Moriches & Shinnecock • “Fork Bays:” The Peconics (& others) • Inputs from Rivers (Conn. + LI) • Long Island Sound
If time permits • 2 “Waterbody” Case Studies • LIS • Shinnecock Bay
Long Island Sound • Important economically and recreationally • 8 million people in watershed, 21 million w/i 50 mile radius “impact area!” • Local residents are the main contributors to the Sound’s degradation • runoff from lawn fertilizing leads to increased nutrients and hypoxia • pathogens enter the food web of the Sound through poor sewage treatment & pet wastes • improper garbage disposal leads to floatable debris
Long Island Sound • 110 miles long (from East River to the Race) • 21 miles wide (Conn. River) • 60-300’ deep (thus SHALLOW - average = 65’; Statue of Liberty is 151’!) • temp. 32-75 degrees F • 1300 square miles • Estuary with two openings to the ocean • 1200 invertebrate and 170 fish species associated (w/ mammals/birds too!)
Long Island Sound • Estuary w/ “salt” water from Atlantic Ocean and 90% of “fresh” water from 3 rivers (Thames, Housatonic, Connecticut) w/ remaining 10% from LI Rivers and groundwater/other sources • Semidiurnal tides influence salinity • Local major Carbon dioxide “sponge” on North Shore • Local area of interest: Port Jefferson Harbor
The “Race” • (Remember) LIS is 110 miles long (from East River to the Race) • Narrowest, Eastern, water entry pt. from Ocean • Current = 5 knots; thus if you go through at “Fair Tide” (when currents move to right) you can go 4 knots but if you try to head windward you go BACKWARDS 1 knot (that’s how powerful water moves through skinny area) • 25 billion gallons/daily funnel through thus 350’ deep (deepest LIS pt.)
Local Case Study • Shinnecock Bay
Where is Shinnecock Bay? • Shinnecock Bay is located on the South Shore of Long Island, NY (i.e. the “Hamptons” and Quogue). • It is about 75 miles east of New York City • Shinnecock Bay is about 9,000 acres including open water, salt marshes, intertidal flats, and barrier beaches. • This boundary encloses a significant habitat for fish and shellfish, migrating and wintering waterfowl, colonial nesting water birds, beach-nesting birds, migratory shorebirds, raptors, and rare plants
Average depths/characteristics • The western portion of the bay are an average depth of about 2 meters (6 feet) or less; the eastern portions of the bay are about 3 meters in depth. • The shallow waters are very highly productive; the most productive areas are the mudflats, and the salt marshes. • The deeper water habitats are mainly composed of eel grass and sandy shoals; the eel grass beds provide an excellent habitat for many species (offering cover and also a nursery for these organisms).
The organisms • There are many species in or around Shinnecock Bay that are federally listed as threatened or endangered. • Some of which include:
More organisms • Some animals found around Shinnecock Bay which are not endangered or threatened include:
Where does all the water come from? • On the east of the Bay there is an inlet (an inlet can be defined as an indentation of a shoreline, usually long and narrow). • This inlet is connected to the Atlantic Ocean.
Where did the inlet come from? • In 1938 there was a large hurricane (Category 3) and the inlet was created by the storm surge. • The storm surge carved out a large section of the barrier island separating Shinnecock Bay from the Atlantic Ocean.
Ponquogue Bridge, Shinnecock Bay • Since Shinnecock Bay is in the Northeast United States, it has semidiurnal tides (two high tides and two low tides each lunar day). • The highest tide at this location is 2.8 feet • The lowest tide is 0 feet
The tide takes longer to get to the further parts of the bay. This is why there are different times of high and low tides for the different locations in the bay.