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One exception to this trend is a hot spot, rising from the mantle underneath central Germany, which has been responsible in geologic time for volcanoes such as the Vogelsberg in Hesse and currently provides heat to hot springs and lakes in the region. Weathering mantles made up of saprolite are common in Europe.
Volcanoes are usually mountains (sometimes islands, lakes, plateaus, calderas, seamounts or lava domes) that are formed when magma (liquid rock) wells up from inside the Earth. There are also analogous formations away from the Earth. Many volcanoes are categorized both as volcanoes and other landforms, such as mountains (if qualified).
Volcanoes, he said, were formed where the rays of the sun pierced the earth. The volcanoes of southern Italy attracted naturalists ever since the Renaissance led to the rediscovery of Classical descriptions of them by wtiters like Lucretius and Strabo. Vesuvius, Stromboli and Vulcano provided an opportunity to study the nature of volcanic ...
GCSE Bitesize was launched in January 1998, covering seven subjects. For each subject, a one- or two-hour long TV programme would be broadcast overnight in the BBC Learning Zone block, and supporting material was available in books and on the BBC website. At the time, only around 9% of UK households had access to the internet at home.
Erta Ale means "smoking mountain" in the local Afar language and its southernmost pit is known locally as "the gateway to hell". In 2009, it was mapped by a team from the BBC using three-dimensional laser techniques, [ 6 ] in order for the mapping team to maintain a distance and avoid the lakes' searingly hot temperatures.
A volcano needs a reservoir of molten magma (e.g. a magma chamber), a conduit to allow magma to rise through the crust, and a vent to allow the magma to escape above the surface as lava. [16] The erupted volcanic material (lava and tephra) that is deposited around the vent is known as a volcanic edifice, typically a volcanic cone or mountain. [16]
There were three main shield volcanoes built on the seamount base (from north to south): the Northern Edifice, the Central Edifice and the Jandia Edifice. [73] [74] The central shield volcano is the oldest, built mostly from 22 to 18 Ma but with a later phase from 17.5 to 13 Ma. The southern shield volcano formed from 21 to 14 Ma.
Great Britain does not have any active volcanoes now, but has had an active volcanic past. The last active volcanoes stopped erupting about 60 million years ago and the islands are no longer located upon any tectonic boundary or active volcanic region, nor are there other geological phenomena in the island group able to give rise to active ...