Stóra-Eldborg undir Geitahlíð (; also Stóra-Eldborg við Geitahlíð ) is a small

Holocene The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene togethe ...

volcano in

Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...

, on

Reykjanes Reykjanes () is a small headland on the southwestern tip of the Reykjanes Peninsula in Iceland, giving the main peninsula its name. The region is about from Iceland's international airport. As the name means "smoking peninsula" connected to volc ...

peninsula, 50 m high,Íslandshandbókin. Náttúra, saga of sérkenni. Reykjavík 1989, p. 45 with a 30 m deep

crater Crater may refer to: Landforms *Impact crater, a depression caused by two celestial bodies impacting each other, such as a meteorite hitting a planet *Explosion crater, a hole formed in the ground produced by an explosion near or below the surfac ...

.Reynir Ingibjartsson: 25 Gönguleiðir á Reykjanesskaga. Náttúrann við Bæjarveggin. Reykjavík , p.112 - 117 It is located at about 5 km from

Krýsuvík ''For the volcanic landforms around Krýsuvík, see also: Krýsuvík (volcanic system)'' Krýsuvík (also Krísuvík, both pronounced in Icelandic) is an area in Southwest Iceland at about 35 km from Reykjavík. Geography and access It i ...

and as the name says at the foot of a bigger mountain, the

tuya A tuya is a flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are rare worldwide, being confined to regions which were covered by glaciers and had active volcanism during the same period. As lava ...

of ''Geitahlíð''.

Volcanism

Eruption fissures of the Brennisteinsfjöll volcanic system

Despite its location, just some 5 km from the high temperature area of Seltún, the volcano and its counterparts, the crater rows, fissures, as well as the

''Geitahlíð'' (385 m) with the crater Æsubúðir on its top, are not part of the Krýsuvík volcanic system, but of the volcanic system of

Brennisteinsfjöll Brennisteinsfjöll (, "Sulfur mountains"
Brennisteinsfjöll. Detailed description. In: Catalogue of Icelandic Volcanoes ...

as its southernmost outpost. Eldborgir erupted about 2400 BP. The crater row also includes some

lava channel A lava channel is a stream of fluid lava contained within zones of static (i.e., solid and stationary) lava or lava levees. The initial channel may not contain levees per se, until the parental flow solidifies over what develops into the channel and ...

s. The lava at time of eruption run 2,5 km to the sea.

The pyroclastic cones

Stóra-Eldborg undir Geitahlíð is a

pyroclastic cone Volcanic cones are among the simplest volcanic landforms. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and s ...

, built up mostly from spatter and

scoria Scoria is a pyroclastic, highly vesicular, dark-colored volcanic rock that was ejected from a volcano as a molten blob and cooled in the air to form discrete grains or clasts.Neuendorf, K.K.E., J.P. Mehl, Jr., and J.A. Jackson, eds. (2005) ''G ...

it forms part of a crater row. Another such eruption fissure is to be found nearby, therefore Icelanders prefer the plural ''Eldborgir undir Geitahlíð''. One of the eruption fissures dissects the older tuya Geitahlíð. The ''Litla-Eldborg'' crater is part of the parallel crater row and eruption fissure. The eruption products of both fissures are petrologically different when compared. For this reason, it has been thought, that the fissures are not from the same eruption series.Helgi Páll Jónsson: Eldfjallagarður og jarðminjasvæði á Reykjanesskaga. Jarðvísindadeild Háskóli Íslands 2011. MS ritgerð. Leiðbeinendur Ólafur Ingólfsson.
Skoðað 17. ágúst 2020. Litla-Eldborg regrettably is rather damaged by quarrying.

Tuya Geitahlíð

The pyroclastic cones bear their name, because they are located very near to the

Geitahlíð (386 m), and one of the fissures even can be seen dissecting the side of the older volcano. The tuya has its origin in subglacial eruptions under a

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

glacier during a cold spell of Ice Age. A

crater is located up on summit plateau of the tuya which produced the lava field Krýsuvíkurhraun. It entered the sea to the south and formed the upper layers at

urbjarg.

Fólk tales

The location is connected to the fólk tale about the cousins ''Krýsa'' and ''Herdís''. The old women, who could use witchcraft, had a hefty discussion about the borders of their respective lands. One wanted to cast a spell so that all the fish in a nearby lake would be hairy, the other intended to bring up a storm and let all fishermen die. But this did not happen. Instead, the dispute ended with the death of both of them. The fólk tale says that they were buried side by side and the place of the graves is still known to locals.

Nature protection

The crater and its surroundings were placed under nature protection in 1987 as a natural monument inside of Reykjanesfólkvangur.Circumpolar protected areas monitoring. CAFF Monitoring Meeting No. 5, Report, March 2011. Retrieved 30 July 2020.
/ref>

Hiking

There are some – partially marked - hiking trails on the eruption fissure, up to the rim of the Stóra-Eldborg-Crater and in the vicinity. Reynir Ingibjartsson also proposes a tour up on the tuya through a small valley behind Stóra-Eldborg to visit the crater up on the tuya and because of the view over all of the south coast of Reykjanes as well as over other parts of Iceland's south coast up to

Eyjafjallajökull Eyjafjallajökull (; ), sometimes referred to by the numeronym E15, is one of the smaller ice caps of Iceland, north of Skógar and west of Mýrdalsjökull. The ice cap covers the caldera of a volcano with a summit elevation of . The volcan ...

External links

Stóra-Eldborg next to Geitahlíð. Visit Reykjanes. Official Travel Guide.
*The Environment Agency of Iceland
Umhverfisstofnunn.
(in Icelandic)

References

{{DEFAULTSORT:Stóra-Eldborg undir Geitahlíð Volcanoes of Iceland Volcanic craters Reykjanes Volcanic Belt Brennisteinsfjöll Volcanic System