{"id":{"repo_id":"uwo","oai_identifier":"oai:uwo.scholaris.ca:20.500.14721/19317"},"canonical_url":"https://search.dev.ndltd.org/etd/uwo/oai:uwo.scholaris.ca:20.500.14721/19317","repository":{"repo_id":"uwo","name":"Western University","base_url":"https://uwo.scholaris.ca/server/oai/request"},"display":{"title":"High-Precision ID-TIMS U-Pb Zircon Geochronology of Three Cenomanian Bentonites from the Western Canada Foreland Basin","abstract":"The Western Canada foreland basin contains a rich record of Upper Cretaceous marine | and tectonic change, yet is sparse in biostratigraphically useful fauna that permit | continental and global correlation. However, numerous extensive bentonites have been 1 mapped in Cenomanian strata and traced into the U.S. portion of the basin where relationships to globally correlated ammonite zones can be determined. The X, A-X and Bighorn River bentonites provide important calibration points for the Cenomanian Stage. Single zircon crystals from these bentonites were chemically-abraded and dated using high-precision U-Pb ID-TIMS geochronology techniques. The Pb/ U weighted-mean ages are: 95.87±0.10 Ma for the X-bentonite, 95.67±0.15 Ma for the A-X bentonite, and 94.29±0.13 Ma for the Bighorn River Bentonite (2a confidence level). These new ages establish a more precise maximum age for the Cenomanian/Turonian boundary and allow for more accurate measurements of the timing and rates of Cenomanian tectonic and eustatic activity in western North America.","abstract_html":"The Western Canada foreland basin contains a rich record of Upper Cretaceous marine | and tectonic change, yet is sparse in biostratigraphically useful fauna that permit | continental and global correlation. However, numerous extensive bentonites have been 1 mapped in Cenomanian strata and traced into the U.S. portion of the basin where relationships to globally correlated ammonite zones can be determined. The X, A-X and Bighorn River bentonites provide important calibration points for the Cenomanian Stage. Single zircon crystals from these bentonites were chemically-abraded and dated using high-precision U-Pb ID-TIMS geochronology techniques. The Pb/ U weighted-mean ages are: 95.87±0.10 Ma for the X-bentonite, 95.67±0.15 Ma for the A-X bentonite, and 94.29±0.13 Ma for the Bighorn River Bentonite (2a confidence level). These new ages establish a more precise maximum age for the Cenomanian/Turonian boundary and allow for more accurate measurements of the timing and rates of Cenomanian tectonic and eustatic activity in western North America.","abstract_has_math":false,"creators":["Barker, Ivan R."],"institution":null,"degree_name":"M Sc","degree_level":null,"degree_discipline":"Geology","degree_department":null,"school":null,"contributors":[],"advisors":["Moser, Desmond","Plint, Guy"],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-01-01","date_published":"2009-01-01","updated_at":"2026-07-27T21:55:59Z","subjects":["U-Pb Isotope Geochronology","Tephrochronology","Upper-Cretaceous","Cenomanian","ID-TIMS","Zircon","Bentonite","Western Canada Foreland Basin","Stratigraphy","Blackstone Formation","Dunvegan Formation","Eustasy","Tectonics"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/20.500.14721/19317","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Moser, Desmond","Plint, Guy"]},{"key":"dc:creator","label":"Author","values":["Barker, Ivan R."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-06-25T19:01:12Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-06-25T19:01:12Z"]},{"key":"dc:date.issued","label":"Date","values":["2009-01-01"]},{"key":"dc:type","label":"Dc Type","values":["thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Geology"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M Sc"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["U-Pb Isotope Geochronology","Tephrochronology","Upper-Cretaceous","Cenomanian","ID-TIMS","Zircon","Bentonite","Western Canada Foreland Basin","Stratigraphy","Blackstone Formation","Dunvegan Formation","Eustasy","Tectonics"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/20.500.14721/19317"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The Western Canada foreland basin contains a rich record of Upper Cretaceous marine | and tectonic change, yet is sparse in biostratigraphically useful fauna that permit | continental and global correlation. However, numerous extensive bentonites have been 1 mapped in Cenomanian strata and traced into the U.S. portion of the basin where relationships to globally correlated ammonite zones can be determined. The X, A-X and Bighorn River bentonites provide important calibration points for the Cenomanian Stage. Single zircon crystals from these bentonites were chemically-abraded and dated using high-precision U-Pb ID-TIMS geochronology techniques. The Pb/ U weighted-mean ages are: 95.87±0.10 Ma for the X-bentonite, 95.67±0.15 Ma for the A-X bentonite, and 94.29±0.13 Ma for the Bighorn River Bentonite (2a confidence level). These new ages establish a more precise maximum age for the Cenomanian/Turonian boundary and allow for more accurate measurements of the timing and rates of Cenomanian tectonic and eustatic activity in western North America."]},{"key":"dc:title","label":"Title","values":["High-Precision ID-TIMS U-Pb Zircon Geochronology of Three Cenomanian Bentonites from the Western Canada Foreland Basin"]}]}],"canonical_facts":{"dc:contributor.advisor":["Moser, Desmond","Plint, Guy"],"dc:creator":["Barker, Ivan R."],"dc:date.accessioned":["2025-06-25T19:01:12Z"],"dc:date.available":["2025-06-25T19:01:12Z"],"dc:date.issued":["2009-01-01"],"dc:description.abstract":["The Western Canada foreland basin contains a rich record of Upper Cretaceous marine | and tectonic change, yet is sparse in biostratigraphically useful fauna that permit | continental and global correlation. However, numerous extensive bentonites have been 1 mapped in Cenomanian strata and traced into the U.S. portion of the basin where relationships to globally correlated ammonite zones can be determined. The X, A-X and Bighorn River bentonites provide important calibration points for the Cenomanian Stage. Single zircon crystals from these bentonites were chemically-abraded and dated using high-precision U-Pb ID-TIMS geochronology techniques. The Pb/ U weighted-mean ages are: 95.87±0.10 Ma for the X-bentonite, 95.67±0.15 Ma for the A-X bentonite, and 94.29±0.13 Ma for the Bighorn River Bentonite (2a confidence level). These new ages establish a more precise maximum age for the Cenomanian/Turonian boundary and allow for more accurate measurements of the timing and rates of Cenomanian tectonic and eustatic activity in western North America."],"dc:identifier.uri":["https://hdl.handle.net/20.500.14721/19317"],"dc:subject":["U-Pb Isotope Geochronology","Tephrochronology","Upper-Cretaceous","Cenomanian","ID-TIMS","Zircon","Bentonite","Western Canada Foreland Basin","Stratigraphy","Blackstone Formation","Dunvegan Formation","Eustasy","Tectonics"],"dc:title":["High-Precision ID-TIMS U-Pb Zircon Geochronology of Three Cenomanian Bentonites from the Western Canada Foreland Basin"],"dc:type":["thesis"],"thesis:degree_discipline":["Geology"],"thesis:degree_name":["M Sc"]},"updated_at":"2026-07-27T21:55:59Z"}