igh-Resolution Late Devonian Magnetostratigraphy From the Canning Basin, Western Australia: A Re-Evaluatio

Autor(es)

Green, Theodore ^[1] ; Slotznick, Sarah P. ^[1] ; Jaqueto, Plinio ^[2] ; Raub, Timothy D. ^[3] ; Tohver, Eric ^[2] ; Playton, Ted E. ^[4] ; Haines, Peter W. ^[5] ; Kirschvink, Joseph L. ^{[6, 7]} ; Hocking, Roger M. ^[5] ; Montgomery, Paul ^[4]

Afiliação do(s) autor(es)

^[1] Dartmouth Coll, Dept Earth Sci, Hanover, NH 03755 - USA

^[2] Univ Sao Paulo, Inst Astron Geofis & Ciencias Atmosfer, Sao Paulo - Brazil

^[3] Univ St Andrews, Sch Earth & Environm Sci, St Andrews, Fife - Scotland

^[4] Chevron, Frontier Explorat & Appraisal, Houston, TX - USA

^[5] Geol Survey Western Australia, East Perth, WA - Australia

^[6] CALTECH, Div Geol & Planetary Sci, Pasadena, CA 91125 - USA

^[7] Tokyo Inst Technol, Earth Life Sci Inst, Tokyo - Japan

• Tipo de documento: Artigo Científico
• Fonte: Frontiers in Earth Science; v. 9, NOV 24 2021.
• Citações Web of Science: 0

Resumo

Late Devonian time was a period of rapid upheaval in the Earth system, including climate change, sea level changes, widespread ocean anoxia, and the Frasnian-Famennian mass extinction; the cause(s) of these changes remain(s) uncertain. The Lennard Shelf of the Canning Basin in Western Australia contains carbonate reef sections spanning much of the Late Devonian Epoch and has been sampled for paleomagnetic analysis with studies by Hansma and colleagues in 2015 and Playton and colleagues in 2016. However, previous paleomagnetic directions were scattered and their use for magnetostratigraphy has been questioned. Here, rock magnetic data and magnetostratigraphy for a late Devonian drill-core from the Lennard Shelf were analyzed. Three magnetostratigraphic interpretations were made using different paleopoles that showed good correlation with each other and the earlier interpretations by Playton and colleagues in 2016. Additionally, the rock magnetic data revealed the samples contain various mixtures of detrital and diagenetic minerals, the former of which should be viable recorders of primary magnetic signatures. Even in samples with these detrital phases, paleomagnetic data were often noisy and produced ambiguous polarity assignments, likely due to the anomalously weak Devonian field. Because of this ambiguity and the absence of a robust paleopole, broader correlations for this critical time-period will be difficult without additional paleomagnetic data from the late Devonian Period. Expanded data for this interval could eventually shed light on the timing, causes, and rates of the Frasnian-Famennian mass extinction and other environmental shifts in the late Devonian Epoch. (AU)

• Processo FAPESP: 16/24870-2 - Significado ambiental do magnetismo em espeleotemas
• Beneficiário: Plinio Francisco Jaqueto
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 19/06709-8 - Magnetismo em espeleotemas do último máximo Glacial até o Holoceno na América do Sul
• Beneficiário: Plinio Francisco Jaqueto
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado