The Blake Event recorded near the Eemian type locality – A diachronic onset of the Eemian in Europe

Abstract

a b s t r a c tMultidisciplinary analysis including paleomagnetic, sedimentologic, sea-level change, luminescence dating and palynologic research was performed on a 25 m long orientated core taken at Rutten, close to Eemian key localities in the Netherlands. The main goal of our research was to test a possible delayed onset of temperate conditions in this region compared to Southern Europe, occurring within the Last Interglacial. The sediments revealed the presence of the paleomagnetic Blake Event in ca. 10 m of lowerdeltaic floodbasin sediments that contain a pollen record covering the Eemian. The position of the Blake Event in relation to the pollen stratigraphy concurs with the earlier studied Neumark Nord 2 site. Paleomagnetic correlation to core MD95-2042 off SW Iberia indicates ca. 5 kyr diachroneity between the pollen-based onset of temperate interglacial conditions between northern and southern Europe. The onset of the Eemian in north-western and central Europe (ca. 121.0 ka) post-dates the Marine Isotope Stage 6/5e transition by ca. 10 kyr. In addition, the Rutten data provide evidence for a relatively long duration of the Blake Event of at least 8 kyr. The late onset of the temperate conditions that define the base of the Eemian, imply that NW Europe with the Eemian type area is not the most suited region to define the beginning of the Last Interglacial and Late Pleistocene for global chronostratigraphic use.

Formal subdivision of the Quaternary System/Period: Past, present, and future

“…These authors concluded that it began~121.5 ka and lasted to at least 113.5 ka. The results presented by Sier et al (2015) suggest that the start of the Eemian interglacial climatic event was delayed by 5000 years in northwest Europe compared to that in southern Europe e a point originally proposed by Kukla et al (2002). The latter authors suggested that the Eemian Stage interglacial in western Europe lasted for 17,000 or even 23,000 yr based on comparison of the marine and southern European terrestrial biostratigraphies.…”

“…They have arisen following detailed paleomagnetic studies by Sier et al (2011Sier et al ( , 2015 and that have identified and compared the palaeomagnetic Blake Event at sites in northwestern, central, and southern Europe. This event can be applied as a chronostratigraphic marker for comparison of records from marine and terrestrial sequences, and between high and low latitudes, although published durations vary from~1 kyr to more than 7 kyr.…”

“…This event can be applied as a chronostratigraphic marker for comparison of records from marine and terrestrial sequences, and between high and low latitudes, although published durations vary from~1 kyr to more than 7 kyr. Sier et al (2015) determined from an analysis of a research core at Rutten, about 75 km northeast of the Amsterdam terminal borehole, that the Blake Event has a minimum duration of 8000 years, but that there is also large geographic variability in the nature of this event. These authors concluded that it began~121.5 ka and lasted to at least 113.5 ka.…”

“…(2) Modeling simulations incorporating ice core data from both Greenland and Antarctica show asynchronous peak temperatures, with North Atlantic high-latitude temperatures lagging southern hemisphere records by several thousand years (Capron et al, 2014). (3) The Blake Event has an inherently unstable nature, and its expression varies with geography (Sier et al, 2015). (4) The eustatic signature should be a globally synchronous proxy for ice volume, but is best observed in shallow and marginal marine settings that may have an incomplete stratigraphy.…”

Characterisation of the Groningen subsurface for seismic hazard and risk modelling

“…The top of this unit gradually changes to medium-and fine-grained sands. During the Eemian interglacial, between 122,000 and 115,000 years ago (Sier et al, 2015), an estuary developed within the former valley system (Figs 1A, 2C). The Eem Formation contains both clay and peat layers.…”