Kvarken Archipelago Example of glacial landforms Laser DEM Jaakko Auri and Olli Breilin Geological Survey of Finland (GTK) Kokkola HC/KA Workshop, Vaasa 1
Carta Marina 1539 Bishop Olaus Magnus 2
Kvarken Archipelago with numbers Area 194 400 ha, 85 % sea area Coast line 2416 km Number of islands and islets 5600 Inhabitants 2500 Water depth 10 15 m, deepest course 25 metres near Holmö Island (Sweden) Brackish water, salt content 4-5 Ice covered 140-150 days per year Water flow 17 000 m 3 per second (from NE to SW) The total size of the KA/HC transboundary serial property is 336,900 hectares. 3
Deglaciation - The history of the Baltic Sea Baltic Ice Lake (early) Baltic Ice Lake (late) Yoldia Sea Ancylus Lake Litorina Sea M. Saarnisto (2003), drawings O. Sallasmaa Possible strait connections between Baltic Ice lake and ice lake in White Sea area 12 000 BP Niko Putkinen (2011). Late Weichselian deglaciation chronology and palaeoenvironments in northern Karelia, NW Russia. Geological Survey of Finland, Espoo 2011. 4
Glacial isostatic land uplift Year 4000 Picture Hanna Virkki (GTK) Botnian Bay High Caost Kvarken Archipelago Botnian Sea Ågren & Svensson 2007 Baltic Sea The main ongoing geological process changes the shoreline and scenery in a span of human life time. 5
Land is arising from the sea, Gåsgrund 1978 ja 2006 Metsähallitus, Photo Seppo Lammi 2006 6
Geology of central area of the Kvarken Archiplago Based on 1:20 000 mapping of Quaternary deposits and formations (Genat 2002 2005) Glacial till Glacial formations, De Geer-moraines Glacial formations, Ribbed-moraines Deep water sediments, silt and clay Glaciofluvial formations, sand and gravel (esker) Littoral deposits, sand and gravel Bedrock outcrops N 10 km 7
Complex flow pattern of the continental ice sheet Age Relation of the Striations Undefined age relation The Youngest Local Direction Older Local Direction The Oldest Local Direction Picture Jukka Ojalainen,GTK 8
Complex flow pattern of the continental ice sheet Hundreds observations of striations Normally 2, often 3 and even 5 different directions 45º 355º N 310º Picture and interpretation Jukka Ojalainen, GTK 9
Geodiversity on glaciated terrain Glacial formations and features created by continental ice sheet Drumlins Flutings Ribbed - moraines De Geer - moraines Hummocky moraine Boulder field Deep water sediments, clay/silt Continental ice sheet Drawings Harri Kutvonen (GTK) 10
De Geer moraine field, Svedjehamn, Björkö Metsähallitus, Photo Seppo Lammi 2006 11
Interpretation by Niko Putkinen 12
Björkö / Svedjehamn De Geer moraines Laser scanning and map Maanmittauslaitos 13
Björkö De Geer moraines Laser scanning and map Maanmittauslaitos 14
Djupskäret Small bedrock outcrops / flutings / De Geer moraines Laser scanning and map Maanmittauslaitos 15
Haggisgrund Drumlins / Flutings / De Geer moraines Laser scanning and map Maanmittauslaitos 16
Ribbed moraines, Valassaaret-islands Picture Metsähallitus 17
Lappören Ribbed moraines / De Geer moraines Laser scanning and map Maanmittauslaitos 18
Flada-klu lagoon-lake series, Lappören Metsähallitus, Photo Seppo Lammi 2006 19
Märaskäret Ribbed moraines / De Geer moraines / beach ridges Laser scanning and map Maanmittauslaitos 20
Littoral deposits Raised beaches and on going littoral processes. Photos Olli Breilin (upper) ja Jukka Ojalainen (lower), Drawings Harri Kutvonen Märäskäret Norrskär 21
Norrskat Ribbed moraines / De Geer moraines Laser scanning and map Maanmittauslaitos 22
Slåttskäret Ribbed moraines / De Geer moraines / Drumlins Laser scanning and map Maanmittauslaitos 23
Bergö gaddarna Rocky terrain / bedrock outcrops Laser scanning and map Maanmittauslaitos 24
Mickelsörarna Ribbed moraine / fluting Laser scanning and map Maanmittauslaitos 25
Rönnskäret / underwater formations (ULTRA) 26
Thank you for your attention! Sampling at Norra Djupörbådan Photo Hannu Kujala;GTK 2004 27