TY - JOUR

T1 - A North Atlantic tephrostratigraphical framework for 130-60 ka b2k

T2 - new tephra discoveries, marine-based correlations, and future challenges

AU - Siwan M., Davis

AU - Peter M., Abbott

AU - Rhian H., Meara

AU - Nicholas J.G., Pearce

AU - William E. N., Austin

AU - Mark R., Chapman

AU - Svensson, Anders

AU - Bigler, Matthias

AU - Rasmussen, Tine L.

AU - Rasmussen, Sune Olander

AU - Farmer, Elizabeth J.

PY - 2014/12/15

Y1 - 2014/12/15

N2 - Building chronological frameworks for proxy sequences spanning 130e60 ka b2k is plagued by difficultiesand uncertainties. Recent developments in the North Atlantic region, however, affirm the potentialoffered by tephrochronology and specifically the search for cryptotephra. Here we review thepotential offered by tephrostratigraphy for sequences spanning 130e60 ka b2k. We combine newlyidentified cryptotephra deposits from the NGRIP ice-core and a marine core from the Iceland Basin withpreviously published data from the ice and marine realms to construct the first tephrostratigraphicalframework for this time-interval. Forty-three tephra or cryptotephra deposits are incorporated into thisframework; twenty three tephra deposits are found in the Greenland ice-cores, including nine newNGRIP tephras, and twenty separate deposits are preserved in various North Atlantic marine sequences.Major, minor and trace element results are presented for the new NGRIP horizons together with ageestimates based on their position within the ice-core record. Basaltic tephras of Icelandic origin dominatethe framework with only eight tephras of rhyolitic composition found. New results from marine coreMD99-2253 also illustrate some of the complexities and challenges of assessing the depositionalintegrity of marine cryptotephra deposits. Tephra-based correlations in the marine environment provideindependent tie-points for this time-interval and highlight the potential of widening the application oftephrochronology. Further investigations, however, are required, that combine robust geochemicalfingerprinting and a rigorous assessment of tephra depositional processes, in order to trace coeval eventsbetween the two depositional realms

AB - Building chronological frameworks for proxy sequences spanning 130e60 ka b2k is plagued by difficultiesand uncertainties. Recent developments in the North Atlantic region, however, affirm the potentialoffered by tephrochronology and specifically the search for cryptotephra. Here we review thepotential offered by tephrostratigraphy for sequences spanning 130e60 ka b2k. We combine newlyidentified cryptotephra deposits from the NGRIP ice-core and a marine core from the Iceland Basin withpreviously published data from the ice and marine realms to construct the first tephrostratigraphicalframework for this time-interval. Forty-three tephra or cryptotephra deposits are incorporated into thisframework; twenty three tephra deposits are found in the Greenland ice-cores, including nine newNGRIP tephras, and twenty separate deposits are preserved in various North Atlantic marine sequences.Major, minor and trace element results are presented for the new NGRIP horizons together with ageestimates based on their position within the ice-core record. Basaltic tephras of Icelandic origin dominatethe framework with only eight tephras of rhyolitic composition found. New results from marine coreMD99-2253 also illustrate some of the complexities and challenges of assessing the depositionalintegrity of marine cryptotephra deposits. Tephra-based correlations in the marine environment provideindependent tie-points for this time-interval and highlight the potential of widening the application oftephrochronology. Further investigations, however, are required, that combine robust geochemicalfingerprinting and a rigorous assessment of tephra depositional processes, in order to trace coeval eventsbetween the two depositional realms

U2 - 10.1016/j.quascirev.2014.03.024

DO - 10.1016/j.quascirev.2014.03.024

M3 - Journal article

VL - 106

SP - 101

EP - 121

JO - Quaternary Science Reviews

JF - Quaternary Science Reviews

SN - 0277-3791

ER -