Provenance of Late Cretaceous to Paleogene rocks of the Alberta Foreland Basin: Rethinking retro-arc drainage systems in the Canadian Cordillera

Super, Samantha Christine

Provenance of Late Cretaceous to Paleogene rocks of the Alberta Foreland Basin: Rethinking retro-arc drainage systems in the Canadian Cordillera

dc.contributor.advisor	Hubbard, Stephen
dc.contributor.author	Super, Samantha Christine
dc.contributor.committeemember	Matthews, William
dc.contributor.committeemember	Enkelmann, Eva
dc.contributor.committeemember	Leckie, Dale
dc.date	2021-11
dc.date.accessioned	2021-05-27T20:17:55Z
dc.date.available	2021-05-27T20:17:55Z
dc.date.issued	2021-05-14
dc.description.abstract	Late Cretaceous to Paleogene strata of the Alberta Foreland Basin preserve a record of sediment dispersal in the Canadian Cordillera during the Laramide Orogeny. The provenance of these strata has only been loosely constrained. Detrital zircon U-Pb geochronology is paired with Lu-Hf isotopic analysis to better constrain the evolution of sediment provenance and dispersal patterns of Western Canada during the Late Cretaceous to Paleogene. Sampled sandstones (N = 19 samples; n = 4096 dates, total) cluster into 4 provenance groups using statistical analysis. The detrital zircon populations of most samples are dominated to some degree by near-depositional Cordilleran magmatic-derived grains and contain zircon populations from Yukon-Tanana Terrane and Intermontane Superterrane rocks. The appearance of a mixed detrital zircon signature refines the onset of the ‘Rundle Pulse’ thrust event in the Foreland Fold and Thrust Belt. Isotopically juvenile zircon grains sourced from the Coast Mountains Batholith are found in Cretaceous to Paleogene wedge strata. The presence of a juvenile isotopic signature in the near-depositional component of zircon populations necessitates a cross-Cordilleran delivery pathway. Transport via airfall ash across the main Cordilleran drainage divide has been previously hypothesized. However, an abrupt change in sediment provenance across the sub-Paskapoo Formation unconformity (ca. 63 Ma) cannot be reconciled with the airfall ash transport mechanism. The results are better explained with a model that invokes fluvial sediment transport of juvenile zircon grains to the foreland directly via integrated cross-Cordilleran river systems. The model shifts the main Cordilleran drainage divide west into the Coast Mountains Batholith or Intermontane Superterrane until Paskapoo Formation deposition. We suggest that the sudden shift in detrital zircon signature observed at the sub-Paskapoo Formation unconformity is associated with river capture and re-routing of fluvial systems west of the fold and thrust belt. These findings have implications for the timing and magnitude of the large-scale tectonics of the North American Cordillera.	en_US
dc.identifier.citation	Super, S. C. (2021). Provenance of Late Cretaceous to Paleogene rocks of the Alberta Foreland Basin: Rethinking retro-arc drainage systems in the Canadian Cordillera (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.	en_US
dc.identifier.doi	http://dx.doi.org/10.11575/PRISM/38895
dc.identifier.uri	http://hdl.handle.net/1880/113454
dc.language.iso	eng	en_US
dc.publisher.faculty	Science	en_US
dc.publisher.institution	University of Calgary	en
dc.rights	University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.	en_US
dc.subject	Alberta Foreland Basin	en_US
dc.subject	Drainage Divide	en_US
dc.subject	Canadian Cordillera	en_US
dc.subject	Detrital Zircon	en_US
dc.subject.classification	Geology	en_US
dc.title	Provenance of Late Cretaceous to Paleogene rocks of the Alberta Foreland Basin: Rethinking retro-arc drainage systems in the Canadian Cordillera	en_US
dc.type	master thesis	en_US
thesis.degree.discipline	Geoscience	en_US
thesis.degree.grantor	University of Calgary	en_US
thesis.degree.name	Master of Science (MSc)	en_US
ucalgary.item.requestcopy	true	en_US