People at Fort Hoofddijk

Vika Tomsha
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Visiting 
Mrs. V. A. Tomsha
Paleomagnetic Laboratory
Fort Hoofddijk
Department of Earth Sciences, 
Utrecht University 
Budapestlaan 17, 3584 CD Utrecht 
The Netherlands 

Phone +31 30 253 5481
Fax +31 30 243 1677
E-mail tomsha@geo.uu.nl

Research
Publications
 
Usually at:
VNIGRI
Liteiny Av. 39, 
St. Petersburg, 191104, Russia
e-mail:
 
Bucharest University


Research of Vika Tomsha

Paleoenvironmental and paleogeographic evolution of the Black Sea area during the Neogene: Implications for Mediterranean-Paratethys exchange
The northward plate tectonic motion of the African/Arabian continent during the Neogene (24-0 Myrs ago) has led to the closure of the Tethys Ocean. The Alpine- Himalayan orogenic barrier separated this ocean into the Mediterranean domain and the so-called “Paratethys” domain; a large endemic water mass that extended from Austria to Iran, with the Black Sea and Caspian Sea as actual remnants.  Both domains have experienced dramatic paleoenvironmental (and tectonics)  changes during the Neogene, examplified by the desiccation and reflooding of the Mediterranean during the Messinian Salinity Crisis (6-5.3 Myrs ago) and the desiccation and reflooding of the Black Sea during an event that might be related to the biblical flood of Noah (~8 kyrs ago). 

The semi-enclosed land-locked configuration of the Mediterranean region has appeared to be extremely sensitive to record changes in paleoclimate and paleoenvironment and integrated stratigraphic studies have revealed that the sedimentary record accurately reflects astronomically induced changes in solar insolation. This has allowed the construction of very detailed astronomically tuned geological polarity time scales, which at present underlie most modern paleoclimatic, paleoceanographic and paleogeobiologic research efforts. 


Fieldwork in Taman peninsula (Russia)
In contrast, the time scale for the Paratethys domain is highly equivocal and controversial ages exist for many events and geological stage boundaries.
The small marine opening through the Bosporus did not exist during large parts of the Neogene. The key question that hampers a full understanding of the paleoclimatological evolution of Eurasia during that time period thus relates to the closure and opening of the marine connection(s) between Mediterranean and Paratethys, and is at present far from understood.
'Fieldwork' in Loosdrecht (Holland)

publications Publications of Vika Tomsha