Show simple item record

dc.contributor.authorWinn, Cathie Eileen.en_US
dc.date.accessioned2009-07-14T19:41:02Z
dc.date.available2009-07-14T19:41:02Z
dc.date.issued1977-07-14T19:41:02Z
dc.identifier.urihttp://hdl.handle.net/10464/2281
dc.description.abstractThis study has three purposes: to establish a chronologically controlled vegetational history for a number of sites in south Southwestern Ontario; to utilize the resulting data to support and/or add to the current understanding of Quaternary geology and stratigraphy, and the glacial and postglacial history of the Great Lakes in south Southwestern Ontario; and to attempt to propose a possible explanation for the extinction of the mastodon in Southern Ontario. Palynological and geochronological analyses were conducted on material collected from eleven sites (east to west): Verbeke Mastodon Site, Woloshko Mastodon Site, Walker Pond II, Pond Mills I, Lake Hunger Bog, Bouckaert Site. Mabee Site, Cornell Bog. Colles Lake I, Folden Mastodon Site and Forest Pond. Individual geochronologically controlled (where possible) vegetational histories were reconstructed for each of the sites investigated. The results of the individual studies, when considered in overview. indicated the existance of an established closed boreal forest throughout south Southwestern Ontario by 10,000 years B.P. This evidence for a significant climatic change coincident throughout south Southwestern Ontario supports the proposed age of 10,000 years B.P. for the Pleistocene/Holocene Boundary (Terasmae, 1972). Remnant patches of 'open spruce parkland' persisted in small local 'wet' areas. It was in these areas that the mastodon was restricted during early Holocene time. With continued encroachment by the surrounding boreal forest, possibly speeded up by this browser's destructive feeding habits, the spruce enclaves shrank and the mastodon became extinct in south Southwestern Ontario. The results of this thesis basically support Dreimanis' (1967, 1968) proposed 'Environmental-Climatic' theory for mastodon extinction. It is suggested that increased dryness during the present interglacial compared to the climate of earlier interglacials may be the key to unravelling the problem of mastodon extinction in eastern North America.en_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectMastodons.en_US
dc.subjectGeological time.en_US
dc.subjectGeologyen_US
dc.subjectVegetation and climateen_US
dc.titleVegetational history and geochronology of several sites in South Southwestern Ontario with discussion on mastodon extinction in Southern Ontario /en_US
dc.typeElectronic Thesis or Dissertationen
dc.degree.nameM.Sc. Earth Sciencesen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Earth Sciencesen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US
refterms.dateFOA2021-07-16T11:58:45Z


Files in this item

Thumbnail
Name:
Brock_Winn, Cathie_1977.pdf
Size:
17.33Mb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record