Editing Volcanic plug

{{short description|Volcanic object created when magma hardens within a vent on an active volcano}}
{{More citations needed|date=June 2013}}
[[File:Pitonpair.JPG|right|thumb|250px|An aerial view of the [[Gros Piton]] and [[Petit Piton]], in [[St. Lucia]], 2006.]]
A '''volcanic plug''', also called a '''volcanic neck''' or '''lava neck''', is a [[volcano|volcanic]] object created when [[magma]] hardens within a [[Volcanic vent|vent]] on an active volcano. When present, a plug can cause an extreme build-up of high gas [[pressure]] if rising [[Volatile (astrogeology)#Igneous petrology|volatile]]-charged [[magma]] is trapped beneath it, and this can sometimes lead to an explosive eruption.  In a [[plinian eruption]] the plug is destroyed and ash is ejected.<ref name="vlh">{{cite journal |last1=Huff |first1=W.D. |last2=Owen |first2=L.A. |date=2013 |title=Volcanic Landforms and Hazards |url=https://www.sciencedirect.com/science/article/pii/B9780123747396000890 |journal=Treatise on Geomorphology |volume=5 |issue= |pages=155 |doi=10.1016/B978-0-12-374739-6.00089-0 |isbn=9780080885223 |access-date=|url-access=subscription }}</ref>

[[Glaciation|Glacial]] erosion can lead to exposure of the plug on one side, while a long slope of material remains on the opposite side. Such landforms are called [[crag and tail]]. If a plug is preserved, [[erosion]] may remove the surrounding rock while the erosion-resistant plug remains, producing a distinctive upstanding landform.

== Examples of volcanic plugs ==
[[File:Rhumsiki Peak.jpg|thumb|Volcanic plug near [[Rhumsiki]], [[Cameroon]].]]

=== Africa ===
Near the village of [[Rhumsiki]] in the [[Far North Region (Cameroon)|Far North Province]] of [[Cameroon]], Kapsiki Peak is an example of a volcanic plug and is one of the most photographed parts of the [[Mandara Mountains]]. Spectacular volcanic plugs are present in the center of [[La Gomera]] island in the [[Canary Islands]] archipelago, within the [[Garajonay National Park]]. [[Pico_Cão_Grande|The Pico Cão Grande]] (Portuguese for "Great Dog Peak") is a landmark needle-shaped volcanic plug peak in São Tomé and Príncipe, in the Caué District of São Tomé Island in Parque Natural Obô de São Tomé. Its summit is 663 m (2,175 ft) above sea level,[1] and it rises about 370 m (1,210 ft) over the surrounding terrain.[2] 
[[File:Roque Bentayga visto desde Artenara.jpg|thumb|[[Roque Bentayga]] from the town of [[Artenara]]]]

=== Asia ===
[[Sigiriya]] is an ancient rock fortress near the town of [[Dambulla]] in [[Sri Lanka]]. Approximately 180m high, it is now a UNESCO listed [[World Heritage Site]].<ref>{{cite web |last1=Voiland |first1=Adam |title=Sri Lanka's Granite Fortress |url=https://earthobservatory.nasa.gov/images/149543/sri-lankas-granite-fortress |website=NASA Earth Observatory |date=5 March 2022 |access-date=24 November 2024}}</ref>

=== Europe ===
[[File:Rocher St Michel à Aiguilhe.JPG|thumb|upright|[[Saint Michel d'Aiguilhe]] chapel, on top of a volcanic plug in [[Le Puy-en-Velay]], France.]]

[[Borgarvirki]] is a volcanic plug located in north Iceland.

A volcanic plug is situated in the town of [[Motta Sant'Anastasia]] in Italy.

[[Saint Michel d'Aiguilhe]] chapel, whose construction started in 969,<ref>{{Base Mérimée|PA00092565|Eglise Saint-Michel}}</ref> near [[Le Puy-en-Velay]] in France. The volcanic plug rises about {{convert|85|m}} above the surroundings. Another building on a volcanic plug is the 14th century [[Trosky Castle]] in the [[Czech Republic]].  [[Strombolicchio]], the northernmost of the [[Aeolian Islands]], and [[Rockall]], a small, uninhabited, remote [[islet]] in the North [[Atlantic Ocean]], are also volcanic plugs.

In the [[United Kingdom]], two examples of a building on a volcanic plug are the [[Edinburgh Castle|Castle Rock]] in [[Edinburgh]], Scotland, and [[Deganwy Castle]], [[Wales]]. The [[Law, Dundee]], [[Ailsa Craig]], [[Bass Rock]], [[North Berwick Law]] and [[Dumgoyne]] hill are other examples of volcanic plugs located in [[Scotland]]. There are over 30 volcanic plugs in [[Northern Ireland]], including [[Slemish]] in [[Ballymena]], [[Tievebulliagh]], [[Scawt Hill]], [[Carrick-a-Rede Rope Bridge|Carrickarede]], [[Scrabo Tower|Scrabo]] and [[Slieve Gallion]].<ref name="hmso">Wilson, H E et al (1986) Geological Survey of Northern Ireland, HMSO</ref>

=== North America and the Caribbean === 

There are several volcanic plugs in the [[United States]], including [[Morro Rock]] in [[California]], Devils Elbow located in the [[Heceta Head Lighthouse]] Scenic State Park on the [[Oregon]] coast, Thumb Butte in the [[Sierra Prieta]] of Arizona, and [[Shiprock]] in [[New Mexico]]. [[Devils Tower]] in [[Wyoming]] and [[Little Devils Postpile]] in [[Yosemite National Park]], California, are also believed, by many [[geologist]]s, to be volcanic plugs.  In Canada, the [[Northern Cordilleran Volcanic Province]] gives rise to several confirmed and suspected plugs. Chief among these is [[Castle Rock (volcano)|Castle Rock]], located in [[British Columbia]], which last erupted during the [[Pleistocene]].  The southern coast of [[Saint Lucia]] is dominated by the iconic [[Pitons (Saint Lucia)|Pitons]], a [[UNESCO]] [[World Heritage Site]]. The twin peaks, Gros Piton and Petit Piton, steeply rise more than {{convert|770|m|ft}} above the [[Caribbean Sea|Caribbean]].

=== South America ===

[[Pinnacle Rock (Galápagos)|Pinnacle Rock, Galápagos, Ecuador]].

=== Oceania === 

There are several volcanic plugs in the [[North Island]] of [[New Zealand]], including:
* the Pinnacles in the [[Coromandel Peninsula]]
* [[Bream Head]] in [[Northland Region|Northland]]
* Paritutu and the adjacent [[Sugar Loaf Islands]] in [[Taranaki]]
* St. Paul's Rock at [[Whangaroa Harbour]]
* [[Piha]]'s Lion Rock, which hosted a fortified [[Māori people|Maori]] [[pā]]
* Mount Pohaturoa near the village of [[Ātiamuri]], a distinctive sight for travelers along [[State Highway 1 (New Zealand)|State Highway 1]]

In New Zealand's [[South Island]], [[Ōnawe Peninsula|Onawe Peninsula]] on [[Banks Peninsula]] is a prominent volcanic plug, and erosion of [[Saddle Hill (New Zealand)|Saddle Hill]] near [[Dunedin]] has also revealed a plug. Dunedin's [[Mount Cargill]] displays two plugs: its main summit and the subsidiary summit of Buttar's Peak.

In [[Australia]], [[The Nut (Tasmania)|The Nut]] in [[Tasmania]] are further examples, along with [[Mount Warning]] and the several peaks in the [[Warrumbungles]] in New South Wales. The 11 peaks of the [[Glass House Mountains National Park|Glasshouse Mountains National Park]] including [[Mount Beerwah]], [[Mount Tibrogargan]], [[Mount Coonowrin]], [[Mount Cooroora]], [[Mount Ngungun]], Mount Tibberoowuccum, Mount Tunbubudla, and Mount Beerburrum, in [[South East Queensland]] are volcanic plugs.<ref>{{cite web |url=https://www.australia.com/en/places/brisbane-and-surrounds/guide-to-the-glass-house-mountains.html |title=Guide to the Glass House Mountains – Tourism Australia |date=21 July 2021 }}</ref><ref>{{cite web
 |url= http://www.geomaps.com.au/scripts/mountwarning.php
 |work= Geological sites of NSW
 |title= Wollumbin/Mt Warning Shield Volcano
 |publisher= Cartoscope Pty Limited
 |access-date= 30 June 2013
}}
</ref>

== Gallery ==
<gallery mode="packed" widths="100">
Edinburgh Castle From Princes Street Garden 001.jpg|[[Edinburgh Castle]] in [[Scotland]] is built upon an [[Castle Rock (Edinburgh)|ancient volcanic plug]].
Mt Popa.jpg|[[Mount Popa|Taung Kalat]], Burma.
Strombolicchio2.jpg|[[Strombolicchio]] Island and its lighthouse, close to Stromboli Island ([[Aeolian Islands]], Italy).
RoqueNublo2.jpg|[[Roque Nublo]], symbol of [[Gran Canaria]] island.
Slemish (8) - geograph.org.uk - 834986.jpg|[[Slemish]], a volcanic plug in [[Northern Ireland]], is traditionally associated with [[St Patrick]].
TroskyCastle.JPG|[[Trosky Castle]] ("Panna" Tower), Czech Republic.
Devils_Tower.jpg|[[Devils Tower]], Wyoming, USA.
File:Shiprock.snodgrass3.jpg|[[Shiprock]], New Mexico, USA.
File:Whangaroa_Harbour3.JPG|St. Paul's Rock, above [[Whangaroa Harbour]], Northland, New Zealand.
São Tomé - Pico Cão Grande.jpg|[[Pico Cão Grande]], landmark volcanic plug peak on [[São Tomé Island]] (São Tomé and Príncipe), rising over {{convert|300|m}} above the surroundings.
Dent_de_la_Rancune,_voie_normale.png|Dent de la Rancune, a challenging climbing site in the [[Chaîne des Puys]], France.
File:Crater Bluff Warrumbungles.jpg|Crater Bluff in the [[Warrumbungles]], New South Wales

</gallery>
{{Commons category|Volcanic plugs}}

== References ==
{{Reflist}}

{{Earth's landforms}}

[[Category:Volcanic plugs| ]]
[[Category:Volcanic landforms]]