Environmental control on the occurrence of high-coercivity magnetic minerals and formation of iron sulfides in a 640 ka sediment sequence from Lake Ohrid (Balkans)

The bulk magnetic mineral record from Lake Ohrid, spanning the past 637 kyr, reflects large-scale shifts in hydrological conditions, and, superimposed, a strong signal of environmental conditions on glacial–interglacial and millennial timescales. A shift in the formation of early diagenetic ferrimagnetic iron sulfides to siderites is observed around 320 ka. This change is probably associated with variable availability of sulfide in the pore water. We propose that sulfate concentrations were significantly higher before  ∼  320 ka, due to either a higher sulfate flux or lower dilution of lake sulfate due to a smaller water volume. Diagenetic iron minerals appear more abundant during glacials, which are generally characterized by higher Fe / Ca ratios in the sediments. While in the lower part of the core the ferrimagnetic sulfide signal overprints the primary detrital magnetic signal, the upper part of the core is dominated by variable proportions of high- to low-coercivity iron oxides. Glacial sediments are characterized by high concentration of high-coercivity magnetic minerals (hematite, goethite), which relate to enhanced erosion of soils that had formed during preceding interglacials. Superimposed on the glacial–interglacial behavior are millennial-scale oscillations in the magnetic mineral composition that parallel variations in summer insolation. Like the processes on glacial–interglacial timescales, low summer insolation and a retreat in vegetation resulted in enhanced erosion of soil material. Our study highlights that rock-magnetic studies, in concert with geochemical and sedimentological investigations, provide a multi-level contribution to environmental reconstructions, since the magnetic properties can mirror both environmental conditions on land and intra-lake processes.

Facilitated dialogue in the Balkans vindicates the EEAS. CEPS Commentary, 29 April 2013

As a result of EEAS-led facilitated dialogue, on April 19th the prime ministers of Serbia and Kosovo reached their first agreement on the principles governing the normalisation of relations. The agreement handed Catherine Ashton a diplomatic victory she badly needed and offered proof of the added value of the European External Action Service (EEAS) as a new EU foreign policy actor.

Thessaloniki ten years on: Injecting momentum into the enlargement process for the Western Balkans. CEPS Commentary, 16 May 2013.

Ten years have passed since the EU-Western Balkans summit was held in Thessaloniki in June 2003. In this new CEPS Commentary, CEPS Associate Senior Fellow Erwan Fouéré exhorts the EU to mark the occasion by reaffirming with greater determination the European perspective for the countries of the region in the hope of keeping the Balkan ghosts at bay.

Bilateral Disputes – A dark cloud over the Balkans. CEPS Commentary, 24 January 2014

Countless bilateral disputes continue to plague the Balkan region; daily reminders of the region's troubled history. Not only are they the cause of tension between the countries of the region both inside and outside the EU, they also undermine efforts to integrate the region into the EU. To avoid the risk of instability and further erosion of the credibility of the EU's enlargement strategy, urgent action is required. The author sets out four recommendations for the EU to pursue without delay.