Late Quaternary Events on the Burin Peninsula, Newfoundland with reference to the Islands of St. Pierre et Miquelon (France)

• Main Author: Tucker, Christopher M.
• Other Authors: McCann, S.B., Ford, D.C., Middleton, G.V., Geography
• Format: Thesis
• Language: unknown
• Published: 2009
• Subjects: Geography; Barachois; Ice; Newfoundland; permafrost; wedge*
• Online Access: http://hdl.handle.net/11375/11445

A revised and extended chronology of late Quaternary events on the southeastern coast of Newfoundland indicates that the oldest deposits are pre-Wisconsinan, that mid-Wisconsinan ice was limited, and that the late-Wisconsinan ice margin was near the mainland of Newfoundland. Evidence is derived from morphogenetic mapping of surficial deposits, and studies of infrequent multiple-till sections, raised glaciomarine features, periglacial forms and weathering phenomena. Trace element and stratigraphic analyses suggest that the oldest till units may be Illinoian. A continuous Sangamonian bench at 4 m a.s.l. exists along both coasts of the peninsula. Early-Wisconsinan ice flow was from the island of Newfoundland to the southeast, across the Burin Peninsula and St. Pierre et Miquelon. Marine deposits on the Burin at Dantzic Cove and Salmonier Pond, and Petit Barachois, Langlade (Miquelon) contain foraminifera of proposed, mid-Wisconsinan age. The marine units on the Burin Peninsula are underlain by a silty till and and overlain by a sandy till. On Langlade, they are underlain by glaciomarine unit and capped by aeolian sands. Marine overlap during the mid-Wisconsinan is further indicated by 20 m a.s.l. raised benches on the Burin Peninsula, and a continuous wash limit at approximately the same elevation on St. Pierre et Miquelon. Onshore-directed striae with sequentially weathered facets, and marine sands incorporated in till, indicate that a later ice movement (late, mid-Wisconsinan?) was from a shelf-centred cap on the south coast of the peninsula, and from ice domed to the northeast on the Placentia Bay coast. A late-Wisconsinan, glacial limit, marked by eskers and general ice stagnation terrain, occurs between Terrenceville and Swift Current. The associated marine limit has been recorded at 18 m a.s.l. in upper Fortune Bay and 11 m a.s.l. at the head of Placentia Bay. In situ wood found below high tide at Little St. Lawrence (1080 ± 50 B.P.), and peat covered by marine deposits, located near Point May (5360 ± 70 B.P.), show that the lower portion of the peninsula is submergent, partly as a result of forebulge collapse related to the late-Wisconsinan ice limit. Permafrost activity, following deglaciation, is indicated by the presence of fossil ice wedge casts situated in stratified deposits related to this events. Doctor of Philosophy (PhD)