TY - JOUR

T1 - Last glacial period cryptotephra deposits in an eastern North Atlantic marine sequence: Exploring linkages to the Greenland ice-cores

AU - Abbott, P.M.

AU - Bourne, A.J.

AU - Purcell, C.S.

AU - Davies, S.M.

AU - Scourse, J.D.

AU - Pearce, N.J.

N1 - European Research Council (TRACE project) under the European Union/ERC (259253); UK Natural Environment Research Council (NER/A/S/2001/01189); NERC (NE/L501694/1 ); International Focus Group on Tephrochronology and Volcanism (1307s)

PY - 2015/11/7

Y1 - 2015/11/7

N2 - The establishment of a tephra framework for the Greenland ice-cores spanning the last glacial period, particularly between 25 and 45 Ica b2k, provides strong potential for precisely correlating other palaeoclimatic records to these key archives. Tephra-based synchronisation allows the relative timing of past climatic changes recorded within different depositional environments and potential causal mechanisms to be assessed. Recent studies of North Atlantic marine records have demonstrated the potential of tracing cryptotephra horizons in these sequences and the development of protocols now allows a careful assessment of the isochronous nature of such horizons. Here we report on tephrochronological investigations of a marine sequence retrieved from the Goban Spur, Eastern North Atlantic, covering similar to 25 -60 Ica b2k. Density and magnetic separation techniques and an assessment of potential transport and depositional mechanisms have identified three previously unknown isochronous tephra horizons along with deposits of the widespread North Atlantic Ash Zone II and Faroe Marine Ash Zone III. Correlations between the new horizons and the Greenland ice-core tephra framework are explored and despite no tie-lines being identified the key roles that high-resolution climatostratigraphy and shard-specific trace element analysis can play within the assessment of correlations is demonstrated. The previously unknown horizons are new additions to the overall North Atlantic tephra framework for the last glacial period and could be key horizons for future correlations

AB - The establishment of a tephra framework for the Greenland ice-cores spanning the last glacial period, particularly between 25 and 45 Ica b2k, provides strong potential for precisely correlating other palaeoclimatic records to these key archives. Tephra-based synchronisation allows the relative timing of past climatic changes recorded within different depositional environments and potential causal mechanisms to be assessed. Recent studies of North Atlantic marine records have demonstrated the potential of tracing cryptotephra horizons in these sequences and the development of protocols now allows a careful assessment of the isochronous nature of such horizons. Here we report on tephrochronological investigations of a marine sequence retrieved from the Goban Spur, Eastern North Atlantic, covering similar to 25 -60 Ica b2k. Density and magnetic separation techniques and an assessment of potential transport and depositional mechanisms have identified three previously unknown isochronous tephra horizons along with deposits of the widespread North Atlantic Ash Zone II and Faroe Marine Ash Zone III. Correlations between the new horizons and the Greenland ice-core tephra framework are explored and despite no tie-lines being identified the key roles that high-resolution climatostratigraphy and shard-specific trace element analysis can play within the assessment of correlations is demonstrated. The previously unknown horizons are new additions to the overall North Atlantic tephra framework for the last glacial period and could be key horizons for future correlations

U2 - 10.1016/j.quageo.2015.11.001

DO - 10.1016/j.quageo.2015.11.001

M3 - Article

VL - 31

SP - 62

EP - 76

JO - Quaternary Geochronology

JF - Quaternary Geochronology

SN - 1871-1014

ER -