Investigating potential climatic cycles in glacially-influenced rhythmites of the upper Gowganda Formation using geochemical, sedimentological and spectral analyses

The upper Gowganda Formation of the Huronian Supergroup contains glacially-induced, varve-like rhythmites composed of turbiditic micro-laminae that potentially preserve a detailed record of climatic conditions during the Paleoproterozoic Era. A sedimentological analysis of upper Gowganda Formation deposits enabled identification of eight lithofacies comprising a glaciogenic depositional environment: 1) diamictite, 2) contorted argillite, 3) interlaminated siltstone and sandstone, 4) interbedded siltstone and claystone, 5) sandstone, 6) siltstone, 7) interbedded coarse-grained and fine-grained siltstone, and 8) wavy argillite. Major, trace, and rare earth element analyses indicate that the rhythmites have undergone limited recycling and chemical alteration. Whole-rock δ18O values are consistent with an Archean gneiss provenance and support that chemical weathering and diagenesis were insignificant. Spectral analysis of four rhythmic couplet thickness records using the MTM Toolkit of Mann and Lees (1996) supports the hypothesis of annual deposition for the rhythmites.

Name thesis:degree_name

M Sc

Discipline thesis:degree_discipline

Geology

Grantor dc:publisher

The University of Western Ontario

Year dc:date.issued

2015

Author dc:creator

• Howe, Timothy S

Advisors dc:contributor.advisor

• Patricia Corcoran
• Fred Longstaffe
• Elizabeth Webb

• Paleoproterozoic
• Huronian
• glaciation
• rhythmites
• varves
• micro-laminae

Language dc:language.iso

en_ca

Handle dc:identifier.uri

https://hdl.handle.net/20.500.14721/36262

OAI identifier oai:identifier

oai:uwo.scholaris.ca:20.500.14721/36262