Ancient buried valleys in the city of Tallinn and adjacent area
DOI | 10.3176/earth.2010.1.03 |
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Aasta | 2010 |
Ajakiri | Estonian Journal of Earth Sciences |
Köide | 59 |
Number | 1 |
Leheküljed | 37-48 |
Tüüp | artikkel ajakirjas |
OpenAccess | |
Litsents | CC BY 4.0 |
Eesti autor | |
Keel | inglise |
Id | 13651 |
Abstrakt
The distribution, morphology, fillings, and origin of buried valleys are discussed. The direction of the valleys varies from NW to NE. Within the Viru-Harju Plateau the valleys have a more or less symmetric profile, but asymmetric profiles are dominating in the pre-klint area. They are mainly filled with glacial (till), glaciofluvial (sand, gravel, and pebbles), glaciolacustrine (varved clay), and marine (fine-grained sand) deposits. The Tallinn valley with its tributary valleys (Saku and Sausti) and fore-klint branches (Harku, Lilleküla, and Kadriorg) looks like a river system. The fore-klint branches extend over 20 km in the Gulf of Finland. They are probably tributaries of the ancient river Pra-Neva. Most likely, the formation of valleys was continuous, starting from pre-Quaternary river erosion, and was sculptured by variable processes during the ice ages and influenced by flowing water during the interglacial periods.