Helgrindur

{{Short description|Mountain in Iceland}} {{Use dmy dates|date=August 2022}} {{Infobox mountain | name = Helgrindur | image = Grundarfjørdur 01 (1417674424).jpg | image_caption = Helgrindur behind Grundarfjörður towards the south | elevation_m = 988 | elevation_ref = | prominence = | map = Iceland | map_caption = | map_size = 200 | label_position = right | location = Snæfellsnes peninsula, western Iceland | range = | width = {{convert|2|-|3|km|abbr=on}}<ref name=Jóhannesson2019 /> | length = {{convert|30|km|abbr=on}}<ref name=Jóhannesson2019 /> | coordinates = {{coord|64|52|N|23|18|W|type:mountain_scale:100000|format=dms|display=inline,title}} | coordinates_ref = | topo = | type = Pyroclastic cone(s)<ref name="gvp">{{cite gvp|vn=370020|title=Helgrindur: General Information|accessdate=2024-02-03}}</ref> | age = | last_eruption = Holocene<ref name="gvp"/> | first_ascent = | easiest_route = | image_map ={{maplink|frame=yes|frame-align=center|frame-width=280|frame-height=350|frame-long=-22.8|frame-lat=64.5|zoom=7|raw=[{{Wikipedia:Map data/Snæfellsnes volcanic belt}},{ "type": "Feature", "properties": { "marker-size": "small", "marker-color": "#ff0000", "marker-symbol": "volcano", "title": "Helgrindur" }, "geometry": {"type": "Point", "coordinates":[-23.3, 64.866667]} }]|text=Approximate map of central volcanoes and their fissure fields (paler shading) in the Snæfellsnes volcanic belt:{{legend|#fbb397|Snæfellsjökull}}{{legend|#fbcc97|Helgrindur}}{{legend|#fbdb87|Ljósufjöll}}Mouse over is enabled on clicking the map which also shows some features (yellow) mentioned in the text on the page.<ref name=Jóhannesson2019 /> }} }} '''Helgrindur''' ({{IPA|is|ˈhɛlˌkrɪntʏr̥}}, also known as Lýsuskarð, Lysuhóll or Lysukard)<ref name="gvp"/><ref name=Burney2020>{{cite journal|last1 =Burney|first1 =D.|last2 =Peate|first2 =D.W.|last3 =Riishuus|first3 =M.S.|last4 =Ukstins|first4 =I.A.|year =2020|title =Reconstructing the plumbing system of an off-rift primitive alkaline tuya (Vatnafell, Iceland) using geothermobarometry and CSDs|journal=Journal of Volcanology and Geothermal Research|volume =399|article-number =106914|doi =10.1016/j.jvolgeores.2020.106914|bibcode=2020JVGR..39906914B|doi-access =free}}</ref> is a volcanic mountain range or massif in the middle of the Snæfellsnes peninsula that provides a backdrop to the port of Grundarfjörður. The volcano can be regarded as potentially active, with a risk of lava flows and much more rarely explosive tephra eruptions.<ref name=Jóhannesson2019 /> The range with its prominent peaks, of Tröllkerling at {{convert|891|m|abbr=on}} in its south-east, Böðvarskúla at {{convert|988|m|abbr=on}} and Kaldnasaborgir (Kaldnasi) in its north-west at {{convert|986|m|abbr=on}} is popular with hikers or mountaineers.

== Geography == The {{convert|2|–|3|km|abbr=on}} wide range,<ref name=Jóhannesson2019 /> is in the middle of the Snæfellsnes peninsula and thus divides the northern large bay of Breiðafjörður from the southern bay of Faxaflói. Reykjavík is about {{convert|105|km|abbr=on}} to the range's south across Faxaflói.<ref name=Jóhannesson2019 /> The weather systems in the two large bays are often quite different and the stormy winds across the range are quite notorious and can be heard sometimes at sea level.

== Geology == The range is part of the Snæfellsnes volcanic belt that extends from the prominent stratovolcano Snæfellsjökull and its volcanic system, to the Helgrindur volcanic system and then on via Vatnafell, a tuya,<ref name=Burney2020 /> to the Ljósufjöll volcanic system in an east to west lineament.<ref name=Jóhannesson2019>{{cite web|url =https://icelandicvolcanoes.is/?volcano=HEL|title =Catalogue of Icelandic Volcanoes - Helgrindur|access-date =3 February 2024| publisher =Icelandic Meteorological Office, Institute of Earth Sciences at the University of Iceland, Civil Protection Department of the National Commissioner of the Iceland Police|year=2019|last1 =Jóhannesson|first1 =Haukur}}</ref> It is not currently known if Vatnafell is part of the Helgrindur volcanic system.<ref name=Burney2020 /> The rocks tend to be alkaline hyaloclastite basalt or picrite basalt,<ref name="gvp"/> however a central rhyolite formation is known. In total length there is a {{convert|30|km|abbr=on}} fissure swarm that extends from the south-east into the sea at its north-west.<ref name=Jóhannesson2019 /> The most recent two eruptions were basaltic and must have occurred more than 1100 years ago.<ref name=Jóhannesson2019 /> They are in the mid south portion of the volcanic system.<ref name=Burney2020 /> The oldest rock from the system itself are 1.4 million years old,<ref name=Jóhannesson2019 /> and have been emplaced over a 10 to 7 million year old extinct rift zone basaltic basement.<ref name=Burney2020 /> {{Gallery |Iceland Grundarfjördur.jpg|Grundarfjörur with parts of the Helgrindur mountain range in the background |View from sea.jpg|The mountain range from the Breiðafjörður towards the south-east |Landscape eastern from Arnarstapi (8).jpg|Southern Helgrindur massif }}

== References == {{reflist}}

=== Icelandic sources === * {{cite book|author1=Þorsteinn Jósepsson|author2 =Steindór Steindórsson og Páll Líndal|title =Landið þitt Ísland, H-K|publisher=Örn og Örlygur|year =1982|isbn=}} * {{cite book|author1 =Björn Hróarsson|title= Á ferð um landið, Snæfellsnes|publisher =Mál og menning|year =1994|isbn= 9979-3-0853-2}} {{Volcanoes of Iceland|state=collapsed}}

Category:Mountains of Iceland Category:Snæfellsnes Category:Subglacial volcanoes of Iceland Category:Volcanic systems of Iceland Category:Central volcanoes of Iceland