Lumparn
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The Lumparn ( Finnish Lumpari ) is a large, almost round, land-free area in the archipelago of the Åland Islands, a largely autonomous province in Finland . It is surrounded by four municipalities that border the lake: in the east this is the municipality Lumparland , in the south Lemland , in the west Jomala and in the north Sund , all four of which form the so-called Fasta Åland (mainland) and not the archipelago further east belong. The distance from bank to bank is about 10 kilometers, the water surface about 80 km 2 . The archipelago opening to the east has no closed land connection around the Lumparn. There are only a few, small islands in the bay. The deepest depth is a maximum of 35 m and is located near the east coast. The mean depth is about 20 meters. Despite its size and its small connection to the Åland Sea, the Lumparn is part of the sea and therefore cannot be referred to geographically as an inland sea or an inland lake .
Emergence
The origin of the Lumparn is traced back to a meteoroid impact , which should have been between 1.2 and 0.5 Giga-years (Gya), one Gya corresponds to 10 9 years. Eleven such impacts have been detected in Finland. Typical for extraterrestrial impacts are petrological and geophysical or also morphological features. The size of the diameter of such impacts in Finland varies between about 1.3 and 23 km, and their age from the presumably Mesoproterozoic (~ 1800 mya ) to the late Cretaceous (~ 73 million years BC). The impact Lumparn heard about 9 km in diameter to the average Finnish size.
geology
Since 1989 Lumparn has been geologically investigated more closely. In the final report published in 1997, primary rocks with an age of 1.59 to 1.57 Gya were identified.
On the north bank of the bay, part of the land mass was spared from the Ice Age erosions and limestone from the Ordovician period still shows extraterrestrial deposits. This can only be seen extramaritely in favorable wind conditions and correspondingly low water levels. In other places along the bank, these deposits can be detected by drilling. These deposits consist of quartz, mosaic-like feldspar and other molten fragments.
use
The Lumparn is today a popular and productive fishing ground and an attractive destination for water sports enthusiasts.
Web links
Individual evidence
- ↑ Michael Yarus: Life from on RNA world: the ancestor within. Harvard University Press 2010 , ISBN 0-674-05075-4 , p. 38.
- ↑ a b Summary of the research report of the University of Helsinki ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
Coordinates: 60 ° 9 ′ N , 20 ° 6 ′ E