Scientific Collaboration on Past Speciation Conditions in Lake Ohrid (SCOPSCO) - sedimentstratigraphy, tephrostratigraphy and chronostratigraphy

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The project "Scientific Collaboration on Past Speciation Conditions in Lake Ohrid" (SCOPSCO) established ca. 7 years ago, when a deep drilling full proposal was submitted to the International Continental Scientific Drilling Program (ICDP). Within this proposal, four major aims were defined. These aims are (i) to obtain more precise information about the age and origin of the lake, (ii) to unravel the seismotectonic history of the lake area including effects of major earthquakes and associated mass wasting events, (iii) to obtain a continuous record containing information on volcanic activities and climate changes in the central northern Mediterranean region, and (iv) to better understand the impact of major geological/environmental events on general evolutionary patterns and shaping an extraordinary degree of endemic biodiversity as a matter of global significance. The very successful deep drilling campaign carried out at Lake Ohrid in spring 2013 forms the backbone for answering these aims. During the field campaign, more than 2000 m of sediments were drilled from four different sites in Lake Ohrid. The project applied for here is a renewal proposal and focuses on the main drill site, the DEEP site in the central part of the lake. At this site, overall 1526 m of sediments were recovered from 6 parallel holes with a maximum sediment depth of 569 m below lake floor (blf). As the recovered cores from the individual holes at DEEP site partly overlap, an almost complete composite core can be established, with a recovery of more than 99 % for the uppermost 480 m and a total recovery of more than 95 % for the entire 569 m according to field data. The project here applied for encompasses sedimentological analyses, tephrostratigraphical work, and chronostratigraphical work on the cores from DEEP site, partly in close collaboration with national and international partners, and is addressed to answer the main aims (i), (iii) and (iv) listed above. It will also provide the scientific backbone for all other sedimentological, geochemical and biological/paleontological work on the sediment record carried out by the international scientific community involved into the SCOPSCO project. For the third year of the project, the scientific studies will concentrate on the lower part of the DEEP site sequence, which covers the Mid Pleistocene transition and the period > 1 million years.Preliminary field data and first scientific results indicate that the composite core from the DEEP site spans with a decadal resolution between 1.2 and 1.9 Ma. With the proposal applied for here, the Lake Ohrid record will become a key record for paleoenvironmental changes in the Mediterranean region and for the activity of Italian volcanoes and will allow a unique insight into the mechanisms of speciation and evolution of taxa.