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Wasson Bluff
Wasson Bluff (also known as Wasson's Bluff) is the name applied to a series of imposing cliff faces on the north shore of the Minas Basin about 5 miles (8.5 km) east of the town of Parrsboro, Nova Scotia.〔Thurston, Harry (1994) ''Dawning of the Dinosaurs: The Story of Canada's Oldest Dinosaurs''. Halifax: Nimbus Publishing and The Nova Scotia Museum.〕 The cliffs, which stretch approximately one mile (1.6 km) from Wasson Brook in the east, to Swan Creek in the west, consist of 200-million-year-old rocks that have yielded a wide array of fossils including more than 100,000 bones from Canada's oldest-known dinosaurs as well as the smallest dinosaur tracks ever found.〔Lessem, Don (1992) ''Kings of Creation: How a New Breed of Scientists is Revolutionizing Our Understanding of Dinosaurs''. New York: Simon and Schuster.〕〔Atlantic Geoscience Society (2001)''The Last Billion Years: A Geological History of the Maritime Provinces of Canada''. Halifax: Nimbus Publishing.〕 The fossils date from a critical time in the evolution of life, the boundary between the Triassic and Jurassic geological periods, when mass extinctions led not only to the dominance of the dinosaurs, but also to the evolution of groups of vertebrates, such as fish, crocodiles, frogs and mammals, whose descendants are still alive today.〔 The abrasive action of the tides, considered to be the world's highest, constantly exposes fossils on the cliff faces, shores and seabed.〔〔Thurston, Harry (1990) ''Tidal Life: A Natural History of the Bay of Fundy''. Camden East, Ontario: Camden House Publishing.〕
In 1990, Paul E. Olsen, one of the paleontologists who has conducted extensive fossil excavations at Wasson Bluff wrote: "Every time I stand before these cliffs, I feel dwarfed by the immensity of time."〔
==Geology==
The cliffs at Wasson Bluff stand at the edge of the ancient rift valley known as the Fundy Basin. It was created when the supercontinent Pangaea began to break up about 225 million years ago. As the continental plates moved apart, they ruptured, and blocks subsided or rose along fault lines creating complex, twisted layers of rock turned at odd angles.〔〔〔Roland, Albert E. (1982)''Geological Background and Physiography of Nova Scotia''. Halifax: The Nova Scotian Institute of Science.〕
The orange and red sandstones visible at Wasson Bluff formed as rivers swollen by intense rains carried coarse sediments from nearby highlands into the Fundy Basin. Other deposits came from wind-blown sand dunes or from the sediments on the bottoms of shallow lakes that, at various times, occupied the floor of the basin. As Pangea broke apart, magma rose to the surface through deep fissures in the Earth's crust erupting as lava flows. This massive volcanic activity created the greenish-grey columns and grey-black blocks of basalt that form large sections of the cliffs.〔〔〔
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