Entry to the St. Lawrence River
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To visit The St. lawrence River and its source is at the Tibbetts Point Lighthouse. Drive to site and walk around the grounds, buildings and lighthouse. An easy walk on a paved paths. Open to the public.
From Cape Vincent, the St. Lawrence River passes two US and six Canadian cities before draining into the Gulf of Saint Lawrence, the largest estuary in the world. It runs 1,900 miles from the furthest headwater to the mouth (743.8 miles from the outflow of Lake Ontario). The furthest headwater is the North River in Mesabi Range at Hibbing Minnesota. Its drainage area, which includes the Great Lakes and hence the world’s largest system of fresh water lakes, has a size of 397,685 square miles. The average discharge at the mouth is 367,273 cu ft/s. The river includes three lakes: Lake Saint-Louis south of Montreal, Lac Saint-Francis at Salaberry-de-Valleyfield and Lac Saint-Pierre east of Montreal and encompasses three archipelagoes: the Thousand Islands chain, the Hochelaga Archipelago near Montreal, and the smaller Mingan Archipelago north of Gaspe.
Lake Champlain and the Ottawa, Richelieu, and Saguenay rivers drain into the St. Lawrence.
The St. Lawrence River is in a seismically active zone where fault reactivation is believed to occur along late Proterozoic to early Paleozoic normal faults related to the opening of Iapetus Ocean. The faults in the area rift related, which is called the Saint Lawrence rift system.
The St. Lawrence Valley is a physiographic province of the large Appalachian division, containing the Champlain and Northern physiographic sections.
Lake Ontario is the eastern-most and smallest in surface area (7,540 Square miles) of the Great Lakes, although it exceeds Lake Erie in volume (393 cubic miles). It is the 14th largest lake in the world and has a shore line of 712 miles long.
Lake Ontario has an elevation of 246 feet above sea level. Its length is 193 miles and its width is 53 miles. The average depth is 283 feet, with a maximum depth of 802 feet.
Lake Ontario’s primary inlet is the Niagara River (from Lake Erie) and primary outlet is the St. Lawrence River. Eight major rivers flow into it. Other notable geographic features include Hamilton Harbour, the Bay of Quinte, the Toronto Island, Irondequoit Bay and the Thousand Islands. The largest island on the lake is Wolfe Island located near Kingston at the St. Lawrence River entrance.
Lake Ontario was carved out of soft, weak Silurian rocks by the Wisconsonian ice age glacier, which expanded the preglacial Ontarian River valley of approximately the same orientation. The material that was pushed southward was piled in central and western New York in the form of drumlins, kames, and moraines, which reorganized the entire drainage systems. As the glacier retreated from New York, it still dammed the present St. Lawrence valley, so that the lake was at a higher level. This state is known as Lake Iroquois. During that time the lake drained through present-day Syracuse, New York into the Mohawk River. The old shoreline that was created during his lake stage can be easily recognized by the (now day) beaches and wave-cut hills 10 to 25 miles south of the present shoreline.
When the glacier finally melted from the St. Lawrence valley, the outlet was below sea level, and the lake became for a short time a bay of the ocean. Gradually the land rebounded from the release of the weight of about 6,500 feet of ice that had been stacked on it. It is still rebounding about 12 inches per century in the St. Lawrence area. Since the ice left that area last, that is the area where the most rapid rebound still is occurring. This means that the lake bed is gradually tilting southward, inundating the south shore and turning river valleys into bays. Both north and south shores have shoreline erosion, but the tilting amplifies this effect on the south shore, causing loss to property owners.
To take credit for a find: Take a photo of yourself with the Tibbett’s Point Light house in the backgroundandpost it on the Geocach web page, email the answer the following questions: 1. what objects now standout on Wolfe Island? 2. What makes Wolfe Island a good location for these objects?
3. What is the elevation near the waters edge? Compare your finding with the elevation in the narrative, email your findings. 4. What action has been taken to prevent (or attempt to prevent) further erosion to the shore of Tibbetts Point.
Additional Hints
(Decrypt)
Gurl ner znaznqr naq fgnaq gnyyre guna gur gerrf.