Kvarken Archipelago
Example of glacial landforms – Laser DEM
Jaakko Auri and Olli Breilin
Geological Survey of Finland (GTK) Kokkola
HC/KA Workshop 14.11.2013, Vaasa
J.Auri and O.Breilin
14.11.2013
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Carta Marina 1539
Bishop Olaus Magnus
J.Auri and O.Breilin
14.11.2013
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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 m3 per second (from
NE to SW)
•The total size of the KA/HC
transboundary serial property is 336,900
hectares.
J.Auri and O.Breilin
14.11.2013
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Deglaciation - The history of the Baltic Sea
Baltic Ice Lake (early)
Ancylus Lake
Baltic Ice Lake (late)
Yoldia Sea
Litorina Sea
M. Saarnisto (2003), drawings O. Sallasmaa
Possible strait connections between Baltic Ice Niko Putkinen (2011). Late Weichselian deglaciation chronology and
lake and ice lake in White Sea area 12 000 BP palaeoenvironments in northern Karelia, NW Russia.
Geological Survey of Finland, Espoo 2011.
J.Auri and O.Breilin
14.11.2013
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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.”
J.Auri and O.Breilin
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Land is arising from the sea, Gåsgrund 1978 ja 2006
© Metsähallitus, Photo Seppo Lammi 2006
J.Auri and O.Breilin
14.11.2013
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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
J.Auri and O.Breilin
14.11.2013
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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
J.Auri and O.Breilin
14.11.2013
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Complex flow pattern of the continental ice sheet
Hundreds observations of striations
– Normally 2, often 3 and even 5 different directions
45º
310º
N
355º
Picture and interpretation Jukka Ojalainen, GTK
J.Auri and O.Breilin
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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
J.Auri and O.Breilin
Drawings Harri Kutvonen (GTK)
14.11.2013
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De Geer moraine – field, Svedjehamn, Björkö
© Metsähallitus, Photo Seppo Lammi 2006
J.Auri and O.Breilin
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Interpretation by Niko Putkinen
J.Auri and O.Breilin
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Björkö / Svedjehamn
De Geer moraines
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Björkö
De Geer moraines
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Djupskäret
Small bedrock
outcrops / flutings /
De Geer moraines
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Haggisgrund
Drumlins / Flutings /
De Geer moraines
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Ribbed – moraines, Valassaaret-islands
Picture © Metsähallitus
J.Auri and O.Breilin
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Lappören
Ribbed moraines / De
Geer moraines
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Flada-klu – lagoon-lake series , Lappören
© Metsähallitus, Photo Seppo Lammi 2006
J.Auri and O.Breilin
14.11.2013
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Märaskäret
Ribbed moraines / De
Geer moraines / beach
ridges
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
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Littoral deposits
Raised beaches and on
going littoral processes.
Photos Olli Breilin (upper) ja
Jukka Ojalainen (lower),
Drawings Harri Kutvonen
Märäskäret
Norrskär
J.Auri and O.Breilin
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Norrskat
Ribbed moraines / De
Geer moraines
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Slåttskäret
Ribbed moraines / De
Geer moraines /
Drumlins
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Bergö gaddarna
Rocky terrain /
bedrock outcrops
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
14.11.2013
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Mickelsörarna
Ribbed moraine /
fluting
Laser scanning and map © Maanmittauslaitos
J.Auri and O.Breilin
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Rönnskäret / underwater formations (ULTRA)
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Thank you for your attention !
“Sampling” at Norra Djupörbådan
© Photo Hannu Kujala;GTK 2004
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