| 词条 | Summasjärvi |
| 释义 |
| name = Summasjärvi | image = Summasjarvi.jpg | alt = | caption = | image_bathymetry = | alt_bathymetry = | caption_bathymetry = | location = | coords = {{coord|62|39|N|25|24|E|region:FI_type:waterbody_source:GNS-enwiki|display=title,inline}} | type = Lake | inflow = | outflow = | catchment = Kymijoki | basin_countries = Finland | length = | width = | area = {{convert|21.9|km2|abbr=on}} | depth = {{convert|6.73|m|abbr=on}} | max-depth = {{convert|41|m|abbr=on}} | volume = {{convert|0.147|km3|acre.ft|abbr=on}} | residence_time = | shore = {{convert|50.15|km|abbr=on}} | elevation = | frozen = | islands = Summassaari, Lamposaari | cities = | reference = }} Lake Summanen (Finnish: Summasjärvi, Summanen) is a medium-sized lake of Finland. It is located in Saarijärvi, in the region of Keski-Suomi. There is a Stone Age Museum in the island of Summassaari. The Summanen craterThe 12th impact crater identified in Finland is located at the center of the lake.[1][2] The crater is 2.6 kilometers wide, ~200 meters deep, and mostly buried under later sediments. The age of the crater is not known. It formed before the Quaternary glaciation, but on the other hand after the host rock which formed in the Svecofennian orogeny 1910 million years ago. (Plado et al. assume the impact was Phanerozoic, but give no evidence to support this.[1]) The otherwise shallow lake (depth <10 m) has a 41 m central deep or trench at the crater site. The location is also occupied by a significant, circular electromagnetic anomaly (with more conductive materials at the site).[4] The anomaly is supposedly the result of a 100 to 200 m thick subsurface lens, presumably formed of fractured rock with saline liquids.[2][3] The impact origin was inferred by the anomaly and the deep, and proven by identifying shatter cones and planar deformation features in glacial erratics adjacent to the crater. See also
References1. ^1 {{Cite journal|last=Plado|first=Jüri|last2=Hietala|first2=Satu|last3=Kreitsmann|first3=Timmu|last4=Lerssi|first4=Jouni|last5=Nenonen|first5=Jari|last6=Pesonen|first6=Lauri|date=25 June 2018|title=Summanen, a new meteorite impact structure in Central Finland|url=https://doi.org/10.1111/maps.13134|journal=Meteoritics & Planetary Science|volume=|pages=|via=}} 2. ^1 {{Cite web|url=http://www.tiedetuubi.fi/avaruus/saarijarvelta-keski-suomesta-loytyi-uusi-tormayskraatteri|title=Saarijärveltä Keski-Suomesta löytyi uusi törmäyskraatteri|last=Korteniemi|first=Jarmo|date=26 June 2018|website=Tiedetuubi|archive-url=|archive-date=|dead-url=|access-date=26 June 2018}} 3. ^1 {{Cite book|url=http://tupa.gtk.fi/raportti/arkisto/q19_2243_2244_2007_1.pdf|title=Summasenjärven johtavuusanomalian tutkimukset vuosina 2005 ja 2006|last=Lerssi|first=Jouni|last2=Mursu|first2=Juha|last3=Niskanen|first3=Matti|last4=Pajunen|first4=Hannu|publisher=Geological Survey of Finland|year=2007|isbn=|location=|pages=}}
External links
2 : Impact craters of Finland|Lakes of Saarijärvi |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。