Title | Quaternary geology of St. Anthony - Blanc-Sablon area, Newfoundland and Quebec |
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Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
Author | Grant, D R |
Source | Geological Survey of Canada, Memoir 427, 1992, 60 pages (1 sheet), https://doi.org/10.4095/183880 Open Access |
Year | 1992 |
Document | serial |
Lang. | English |
Maps | Publication contains 1 map |
Map Info. | surficial geology, lithological, 1:125,000 |
Media | paper; on-line; digital |
Related | This publication contains Surficial geology, St.
Anthony-Blanc-Sablon, Newfoundland-Québec |
File format | pdf |
Province | Quebec; Newfoundland and Labrador |
NTS | 2M/03SW; 2M/03NW; 2M/04; 2M/05; 2M/06SW; 2M/06NW; 2M/11SW; 2M/11NW; 2M/12; 2L/13; 2L/14NW; 2L/14SW; 12I/14; 12I/15; 12I/16; 12P/01; 12P/02; 12P/03; 12P/06; 12P/07; 12P/08; 12P/09; 12P/10; 12P/11 |
Area | St. Anthony; Blanc-Sablon; Northern Peninsula; Great Northern Highlands; Highlands of St. John; Grey Islands; Interior Midlands; West Newfoundland Coastal Lowland; Coastal Uplands; White Hills; Forteau
Tablelands; Mecatina Plateau; Labrador |
Lat/Long WENS | -57.5000 -55.2500 51.7500 50.7500 |
Subjects | surficial geology/geomorphology; geochronology; ice movement; ice movement directions; tills; glaciofluvial deposits; marine deposits; fluvial deposits; colluvial deposits; organic deposits; ground ice;
glacial history; glacial deposits; radiocarbon dates; radiometric dates; Wisconsinian Glacial Stage; glacial stages; oxygen isotopes; sea level changes; isotopes; glaciation; Quaternary |
Illustrations | sketch maps; photographs; aerial photographs |
Released | 1993 01 01; 2014 07 15 |
Abstract | The area is a complex of highland plateaus, uplands, and lowlands representing Tertiary planation levels; one surface is a paleoplain with largely inherited glacial relief, which has been exhumed from
Cambrian cover strata. Straddling the Appalachian! Shield margin, the area records the interplay of two ice domains - the Newfoundland ice cap complex and the Laurentide Ice Sheet. Glacial terrains of different geomorphic maturity are attributed to
three main glaciations. The oldest (St. John Zone) records a maximal Laurentide invasion; from relative stream entrenchment, it maybe 400-500 ka (oxygen isotope stage 12). The intermediate-age terrain or Doctors Zone may be stage 6 (Illinoian). It
shows that ice from the Canadian Shield merged with local ice, but left nunataks above 590 m; on Grey Islands, local glaciers occupied cirques that are now submerged 40 m. The last main glaciation (Long Range Zone) is dated to Late Wisconsinan time
by marine deposits. Crosscutting ice flow features define six phases. First, Shield ice crossed Strait of Belle Isle, overran White Hills, and merged with Newfoundland ice below 500 m along an interlobate moraine near the head of Esquiman Channel.
Retreat by calving in deglacial Goldthwait Sea produced 400 De Geer moraines. Glaciers stabilized by 12.6 ka: Long Range ice built the Piedmont Moraines, while Shield ice built the Bradore and Belles Amours moraines at the 150 m marine limit. When
the Polar Front shifted, causing a climatic reversal, Long Range ice readvanced and built the Ten Mile Lake Moraine at 11 ka. The resulting gravitational marine stillstand cut a rock platform (Bay of Islands Surface). A fossil cliff near tide level
records a late Holocene transgression; emergence is now slow or complete. Sporadic ice wedges and palsas are relict from the Little Ice Age, but solifluction and nivation continue above 400 m; cryoturbation is active at sea level. Faulted glacial
pavements suggest neotectonic stress release. |
GEOSCAN ID | 183880 |
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