A tephrostratigraphic record for the last glacial–interglacial cycle from Lake Ohrid, Albania and Macedonia

Abstract

Here we present a tephrostratigraphic record (core Co1202) recovered from the northeastern part of Lake Ohrid (Republics of Macedonia and Albania) reaching back to Marine Isotope Stage (MIS) 6. Overall ten horizons (OT0702-1 to OT0702-10) containing volcanic tephra have been recognised throughout the 14.94 m long sediment succession. Four tephra layers were visible at macroscopic inspection (OT0702-4, OT0702-6, OT0702-8 and OT0702-9), while the remaining six are cryptotephras (OT0702-1, OT0702-2, OT0702-3, OT0702-5, OT0702-7 and OT0702-10) identified from peaks in K, Zr and Sr intensities, magnetic susceptibility measurements, and washing and sieving of the sediments. Glass shards of tephra layers and cryptotephras were analysed with respect to their major element composition, and correlated to explosive eruptions of Italian volcanoes. The stratigraphy and the major element composition of tephra layers and cryptotephras allowed the correlation of OT0702-1 to AD 472 or AD 512 eruptions of Somma-Vesuvius, OT0702-2 to the FL eruption of Mount Etna, OT0702-3 to the Mercato from Somma-Vesuvius, OT0702-4 to SMP1-e/Y-3 eruption from the Campi Flegrei caldera, OT0702-5 to the Codola eruption (Somma-Vesuvius or Campi Flegrei), OT0702-6 to the Campanian Ignimbrite/Y-5 from the Campi Flegrei caldera, OT0702-7 to the Green Tuff/Y-6 eruption from Pantelleria Island, OT0702-8 to the X-5 eruption probably originating from the Campi Flegrei caldera, OT0702-9 to the X-6 eruption of generic Campanian origin, and OT0702-10 to the P-11 eruption from Pantelleria Island. The fairly well-known ages of these tephra layers and parent eruptions provide new data on the dispersal and deposition of these tephras and, furthermore, allow the establishment of a chronological framework for core Co1202 for a first interpretation of major sedimentological changes.

A Late Glacial to Holocene record of environmental change from Lake Dojran (Macedonia, Greece)

“…Bulk organic carbon and carbonate shell samples are more influenced by reservoir effects and have to be regarded more critically, particularly because reservoir effects can vary over time. This was also shown in the records from lakes Prespa and Ohrid (Vogel et al, 2010b;Aufgebauer et al, 2012 and there was no lithological indication for a hiatus or a distinct change in sedimentation rates. However, the age of sample COL 1319.1.1 is also somewhat questionable, as this sample has a very low carbon weight (0.28 mg), and the calendar age is located on a 14 C plateau.…”

Construction of volcanic records from marine sediment cores: A review and case study (Montserrat, West Indies)

“…Magnetic susceptibility is a commonly used, non-destructive tool for identifying tephra horizons in sediment cores (e.g., Hodgson et al, 1998;Takemura et al 2000;Rasmussen et al, 2003;Kutterolf et al, 2008;Vogel et al, 2010). The GeoTek TM MSCL-XYZ multi-sensor core logger, based at BOSCORF, was used to measure magnetic susceptibility at 0.5 cm intervals on split cores using a Bartington MS2E point sensor (Rothwell and Rack, 2006).…”

“…The purpose of this study was not, however, to obtain accurate concentration data for individual layers, but rather to identify relative downcore changes in compositions that might reflect variable abundance of volcanic material. In this context, XRF core-scanning is useful as it is a rapid, non-destructive and high-resolution technique that has, for example, previously been used in palaeoclimate (Palike et al, 2001) and tephrostratigraphy studies (Vogel et al 2010, Brendryen et al 2010Kylander et al 2012). …”

Stratigraphic analysis of lake level fluctuations in Lake Ohrid: an integration of high resolution hydro-acoustic data and sediment cores

“…Although a direct correlation to cores in Ohrid Bay is not possible, prominent reflections of each individual unit (F and G) can be traced to core Co1202 located within the bottomset of the lower terrace assigned to Lithofacies IV (Fig. 2, Vogel et al, 2010b) and therefore are reliably dated to the same age as their corresponding units identified in Ohrid Bay. Within well-stratified sediments of Unit G, a prominent reflection most likely correlates to tephra layer Y-5 found in both cores described in this study as well as in Co1202 (Vogel et al, 2010a, b).…”

“…Beyond that time, dating of lacustrine sediments requires other techniques with generally higher uncertainties. Positioned downwind of most of the Italian volcanoes active during the Quaternary, Lake Ohrid contains a sediment record that is an excellent archive of volcanic ash (Wagner et al, 2008a, b;Vogel et al, 2010b;Sulpizio et al, 2010). Since these tephra layers can be identified and, most importantly, correlated based on their chemical and morphological characteristics to eruptions with known ages, they serve as important stratigraphic and chronological markers.…”