Bündelantrag SCOPSCO: Scientific Collaboration on Past Speciation Conditions in Lake Ohrid - Correlation of Seismic Records with Physical Property and Sedimentological Data

• Applicant: Professor Dr. Sebastian Krastel
• Subject Area: Palaeontology ; Geophysics
• Term: from 2011 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 194242322

• Final Report Year: 2017

Final Report Abstract

Lake Ohrid is a transboundary lake between the Former Yugoslav Republic of Macedonia (FYROM) and Albania. It is considered to be the oldest continuously existing lake in Europe. An extraordinary high degree of endemism, including more than 210 described endemic species, makes the lake a unique aquatic ecosystem of worldwide importance. A deep drilling campaign within the International Continental Scientific Drilling Program (ICDP) took place in spring 2013. Four sites were successfully drilled. The main site (DEEP) in the center of the lake was drilled down to 568.92 m below the lake floor. This project aimed in integrating sediment physical property data into high resolution seismic data collected during several pre-site surveys in between 2004 and 2009. A vertical seismic profile was used to convert Two-Way-Travel-Time into depth allowing a very sound correlation between seismic and drilling data. The age model of the drilling data was successfully applied to the seismic data. The Ohrid basin formed by transtension during the Miocene, opened during the Pliocene and Pleistocene, and the lake established de novo in a relatively narrow valley between 1.9 and 1.3 Ma. Activity at the main boundary faults is ongoing. The pre-rift basement is overlain by fluvial deposits, which in turn are covered by a thick succession of deep-lacustrine sediments. The lake basin can be separated in three areas. The northern part is characterized by extensive faulting and small-scale mass wasting. A thick and undisturbed sedimentary succession is found in the central part. This succession was successfully drilled at the DEEP site. The southern part shows an interlayering of lacustrine sediments and thick slide deposits. Total sediment thickness is significantly reduced compared to the central basin. Lake level reconstructions suggest a general trend from deeper waters from prior to MIS 16 through to MIS 13/12, followed by decreasing water depths with a minimum in MIS 5 and a subsequent deepening to present-day lake level. Pronounced clinoforms at different stratigraphic depth suggest significant short- and/or mid-term lake level changes reflecting changes in water budgets while subsidence is a much slower process. We do not have any indications for a very low lake level or even a dry lake since MIS 16. Hence, Lake Ohrid existed as deep lake since then. The shape and size of the central part of the lake did not change significantly. Lake Ohrid also shows a long history of mass wasting. Mass transport deposits are widespread within the lake but they do cluster at active faults. The only area not affected by mass wasting is the central basin in the area around the DEEP site. The Lini Slide could be linked to an earthquake that took place in the early 6th century. The largest young slide is the Udenisht Slide in the southern part of the lake. We assume that it has the same age as the Lini Slide. The project successfully integrated sediment physical properties into seismic data, hence allowing a sophisticated interpretation of the seismic data. When more data of the remaining cores will become available, we plan to expand our reconstruction of the sedimentary and tectonic evolution of Lake Ohrid especially in the eastern and south-eastern parts of the lake.

Publications

• (2012) Seismic and sedimentological evidence of an early 6th century AD earthquake at Lake Ohrid (Macedonia/Albania). Clim. Past Discuss., 8, 4333–4355, 2012
  Wagner, B., Francke, A., Sulpizio, R., Zanchetta, G., Lindhorst, K., Krastel, S., Vogel, H., Daut, G., Grazhdani, A., Lushaj, B., Trajanovski, S.
  
• (2014) Modeling submarine landslide-generated waves in Lake Ohrid, Macedonia/Albania. In: Submarine mass movements and their consequences (eds: Krastel et al). Advances in Natural and Technological Hazards Research, 37, 497-506
  Lindhorst, K., Krastel, S., Papenberg, C., Heidarzadeh, M.
  
• (2014) More than one million years of history in Lake Ohrid cores. Eos, 95 25-26
  Wagner, B., Wilke, T., Krastel, S., Zanchetta, G., Sulpizio, R., Reicherter, R., Leng, M., Grazhdani, A., Trajanovski, S., Levkov, Z., Reed, J., Wonik, T.
  
• (2014) The SCOPSCO drilling project recovers more than 1.2 million years history from Lake Ohrid. Scientific Drilling, 17, 19-29
  Wagner, B., Wilke, T., Krastel, S., Zanchetta, G., Sulpizio, R., Reicherter, K., Leng, M.J., Grazhdani, A., Trajanovski, S., Francke, A., Lindhorst, K., Levkov, Z., Cvetkoska , A., Reed, J.M., Zhang, X., Lacey, J.H., Wonik, T., Baumgarten, H., Vogel, H.
  
• (2015) Sedimentary and tectonic evolution of Lake Ohrid (Macedonia/Albania). Basin Research. 27, 84-101
  Lindhorst, K., Krastel, S., Reicherter, K., Stipp, M., Wagner, B., Schwenk, T.
  
• (2016) Mass wasting history within Lake Ohrid Basin (Albania/Macedonia) over the last 600 ka. In: Submarine mass movements and their consequences (eds: Lamarche, G. et al). Advances in Natural and Technological Hazards Research, 41, Springer, 291-300
  Lindhorst, K., Krastel, S., Baumgarten, H.
  
• (2017) The environmental and evolutionary history of Lake Ohrid (FYROM/Albania): interim results from the SCOPSCO deep drilling project. Biogeosciences, 14, 2033–2054
  Wagner, B., et al.