The Geological Survey of Finland (GTK) has published the results of an acoustic-seismic survey conducted along the possible routes for a railway tunnel between Helsinki and Tallinn between last August and November.
The results of the survey bode well for the tunnel project, although additional surveys will be required off of the coast of Tallinn.
The survey provides detailed information of the geographical layers and structure of the seabed along the entire route between the two capitals. Additional acoustic-seismic surveys will, however, be necessary to determine the structure of some sediment-covered bedrock depressions outside Tallinn, according to a press release from GTK.
Keijo Nenonen, a senior scientist at GTK, reveals that the survey also found that the basement below the seabed extends practically to the coast of Estonia, to the shoals of Eesti and Naissaare Madal.
The acoustic-seismic survey was conducted between 19 August and 11 November, 2016, on commission from the Helsinki-Uusimaa Regional Council. It was the first in-depth geological survey of its kind to be conducted in the region between Helsinki and Tallinn.
The results of the survey are laid out in a report published in English by GTK. The report as such does not comment on the geotechnical suitability of the basement for excavation but provides new and useful information for further investigations.
Assessments of the economic and technical feasibility of the proposed railway tunnel are to be completed by the end of this year, effectively determining whether or not the project will proceed to its planning phase. The railway tunnel would be approximately 90 kilometres in length and enable roughly 30-minute rail services between Helsinki and Tallinn.
The feasibility assessments are being carried out by FinEst Link, an initiative founded by the City of Helsinki, the City of Tallinn, the Estonian Ministry of Economic Affairs and Communications, the Finnish Ministry of Transport and Communications, the Helsinki-Uusimaa Regional Council and the Harju County Government of Estonia. The initiative is funded partly by the Central Baltic Programme, a programme disbursing EU funding for collaborative cross-border projects in the Baltic Sea Region.
Aleksi Teivainen – HT
Photo: Riku Lumiaro – Lehtikuva
Source: Uusi Suomi