Independent $^{40}$Ar/$^{39}$Ar and $^{14}$C age constraints on the last five glacial terminations from the aggradational successions of the Tiber River, Rome (Italy)

Autor: Eelco J. Rohling, Brian R. Jicha, Paul R. Renne, Fabio Florindo, Alison Pereira, Sébastien Nomade, Fabrizio Marra
Přispěvatelé: Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Roma (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Research School of Earth Sciences [Canberra] (RSES), Australian National University (ANU), Ocean and Earth Science [Southampton], University of Southampton-National Oceanography Centre (NOC), Department of Geoscience [Madison], University of Wisconsin-Madison, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Paléocéanographie (PALEOCEAN), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Muséum national d'Histoire naturelle (MNHN), Ecole française de Rome (EFR), Sezione di Scienze Preistoriche e Antropologiche, Università degli Studi di Ferrara (UniFE), Berkeley Geochronology Center (BGC), Department of Earth and Planetary Science [UC Berkeley] (EPS), University of California [Berkeley], University of California-University of California, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Ferrara = University of Ferrara (UniFE), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC)
Jazyk: angličtina
Rok vydání: 2016
Předmět:
Zdroj: Earth and Planetary Science Letters
Earth and Planetary Science Letters, Elsevier, 2016, 449, pp.105-117. ⟨10.1016/j.epsl.2016.05.037⟩
Earth and Planetary Science Letters, 2016, 449, pp.105-117. ⟨10.1016/j.epsl.2016.05.037⟩
ISSN: 0012-821X
DOI: 10.1016/j.epsl.2016.05.037⟩
Popis: We use 13 new 40Ar/39Ar and 4 new 14C datings of volcanic deposits and organic material found within near-coastal aggradational successions deposited by the Tiber River near Rome, Italy, to integrate a larger dataset previously achieved in order to offer independent age constraints to the sea-level fluctuations associated with Late Quaternary glacial cycles during the last 450 ka. Results are compared with the chronologically independently constrained Red Sea relative sea-level curve, and with the astronomically tuned deep-sea benthic ?18O record. We find good agreements for the timings of change, and in several cases for both the amplitudes and timings of change during glacial terminations T-1, T-2, T-3, and T-5. There is one striking exception, namely for glacial termination T-4 that led into interglacial Marine Isotope Stage (MIS) 9. T-4 in our results is dated a full 18 ka earlier than in the Red Sea and deep-sea benthic ?18O records (which are in good agreement with each other in spite of their independent chronological constraints). The observed discrepancy is beyond the scale of the combined age uncertainties. One possible explanation is that the documented aggradation represents an early phase, triggered by a smaller event in the sea-level record, but the thickness of the aggradational sediment sequence then suggests that the amplitude of this earlier sea-level rise is underestimated in the Red Sea and benthic ?18O records. Also, this would imply that the aggradational succession of the main T-4 deglaciation has not yet been located in the study region, which is hard to reconcile with our extensive fieldwork and borehole coverage, unless unlikely non-deposition or complete erosion. Resolving this discrepancy will improve understanding of the timing of deglaciations relative to the orbitally modulated insolation forcing of climate and will require further focused research, both into the nature and chronology of the Tiber sequences of this period, and into the chronologies of the Red Sea and deep-sea benthic ?18O records.
Databáze: OpenAIRE
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