Dataset Identification:
Resource Abstract:
- description: The word volcano is used to refer to the opening from which molten rock and gas issue from Earth's interior
onto the surface, and also to the cone, hill, or mountain built up around the opening by the eruptive products. This slide
set depicts explosive eruptions, lava fountains and flows, stream eruptions, and fissure eruptions from 19 volcanoes in 13
countries. Volcano types represented in this set include strato, cinder cone, complex, fissure vent, lava dome, shield, and
island-forming. Perhaps no force of nature arouses more awe and wonder than that of a volcanic eruption. Volcanoes can be
ruthless destroyers. Primitive people offered sacrifices to stem the tide of such eruptions and many of their legends were
centered around volcanic activity. Volcanoes are also benefactors. Volcanic processes have liberated gases of the atmosphere
and water in our lakes and oceans from the rocks deep beneath Earth's surface. The fertility of the soil is greatly enhanced
by volcanic eruptive products. Land masses such as islands and large sections of continents may owe their existence entirely
to volcanic activity. The word "volcano" is used to refer to the opening from which molten rock and gas issue from
Earth's interior onto the surface, and also to the cone, hill, or mountain built up around the opening by the eruptive
products. The molten rock material generated within Earth that feeds volcanoes is called magma and the storage reservoir near
the surface is called the magma chamber. Eruptive products include lava (fluid rock material) and pyroclastics or tephra (fragmentary
solid or liquid rock material). Tephra includes volcanic ash, lapilli (fragments between 2 and 64 mm), blocks, and bombs.
Low viscosity lava can spread great distances from the vent. Higher viscosity produces thicker lava flows that cover less
area. Lava may form lava lakes of fluid rock in summit craters or in pit craters on the flanks of shield volcanoes. When the
lava issues vertically from a central vent or a fissure in a rhythmic, jet-like eruption, it produces a lava fountain. Pyroclastic
(fire-broken) rocks and rock fragments are products of explosive eruptions. These may be ejected more or less vertically,
then fall back to Earth in the form of ash fall deposits. Pyroclastic flows result when the eruptive fragments follow the
contours of the volcano and surrounding terrain. They are of three main types: glowing ash clouds, ash flows, and mudflows.
A glowing ash cloud (nue ardente) consists of an avalanche of incandescent volcanic fragments suspended on a cushion of air
or expanding volcanic gas. This cloud forms from the collapse of a vertical ash eruption, from a directed blast, or is the
result of the disintegration of a lava dome. Temperatures in the glowing cloud can reach 1,000 deg C and velocities of 150
km per hour. Ash flows resemble glowing ash clouds; however, their temperatures are much lower. Mudflows (lahars) consist
of solid volcanic rock fragments held in water suspension. Some may be hot, but most occur as cold flows. They may reach speeds
of 92 km per hour and extend to distances of several tens of kilometers. Large snow-covered volcanoes that erupt explosively
are the principal sources of mud flows. Explosions can give rise to air shock waves and base surges. Air shock waves are generated
as a result of the explosive introduction of volcanic ejecta into the atmosphere. A base surge may carry air, water, and solid
debris outward from the volcano at the base of the vertical explosion column. Volcanic structures can take many forms. A few
of the smaller structures built directly around vents include cinder, spatter, and lava cones. Thick lavas may pile up over
their vents to form lava domes. Larger structures produced by low viscosity lava flows include lava plains and gently sloping
cones known as a shield volcanoes. A stratovolcano (also known as a composite volcano) is built of successive layers of ash
and lava. A volcano may consist of two or more cones side by side and is referred to as compound or complex. Sometimes a violent
eruption will partially empty the underground reservoir of magma. The roof of the magma chamber may then partially or totally
collapse. The resulting caldera may be filled by water. The volcanic structure tells us much about the nature of the eruptions.;
abstract: The word volcano is used to refer to the opening from which molten rock and gas issue from Earth's interior
onto the surface, and also to the cone, hill, or mountain built up around the opening by the eruptive products. This slide
set depicts explosive eruptions, lava fountains and flows, stream eruptions, and fissure eruptions from 19 volcanoes in 13
countries. Volcano types represented in this set include strato, cinder cone, complex, fissure vent, lava dome, shield, and
island-forming. Perhaps no force of nature arouses more awe and wonder than that of a volcanic eruption. Volcanoes can be
ruthless destroyers. Primitive people offered sacrifices to stem the tide of such eruptions and many of their legends were
centered around volcanic activity. Volcanoes are also benefactors. Volcanic processes have liberated gases of the atmosphere
and water in our lakes and oceans from the rocks deep beneath Earth's surface. The fertility of the soil is greatly enhanced
by volcanic eruptive products. Land masses such as islands and large sections of continents may owe their existence entirely
to volcanic activity. The word "volcano" is used to refer to the opening from which molten rock and gas issue from
Earth's interior onto the surface, and also to the cone, hill, or mountain built up around the opening by the eruptive
products. The molten rock material generated within Earth that feeds volcanoes is called magma and the storage reservoir near
the surface is called the magma chamber. Eruptive products include lava (fluid rock material) and pyroclastics or tephra (fragmentary
solid or liquid rock material). Tephra includes volcanic ash, lapilli (fragments between 2 and 64 mm), blocks, and bombs.
Low viscosity lava can spread great distances from the vent. Higher viscosity produces thicker lava flows that cover less
area. Lava may form lava lakes of fluid rock in summit craters or in pit craters on the flanks of shield volcanoes. When the
lava issues vertically from a central vent or a fissure in a rhythmic, jet-like eruption, it produces a lava fountain. Pyroclastic
(fire-broken) rocks and rock fragments are products of explosive eruptions. These may be ejected more or less vertically,
then fall back to Earth in the form of ash fall deposits. Pyroclastic flows result when the eruptive fragments follow the
contours of the volcano and surrounding terrain. They are of three main types: glowing ash clouds, ash flows, and mudflows.
A glowing ash cloud (nue ardente) consists of an avalanche of incandescent volcanic fragments suspended on a cushion of air
or expanding volcanic gas. This cloud forms from the collapse of a vertical ash eruption, from a directed blast, or is the
result of the disintegration of a lava dome. Temperatures in the glowing cloud can reach 1,000 deg C and velocities of 150
km per hour. Ash flows resemble glowing ash clouds; however, their temperatures are much lower. Mudflows (lahars) consist
of solid volcanic rock fragments held in water suspension. Some may be hot, but most occur as cold flows. They may reach speeds
of 92 km per hour and extend to distances of several tens of kilometers. Large snow-covered volcanoes that erupt explosively
are the principal sources of mud flows. Explosions can give rise to air shock waves and base surges. Air shock waves are generated
as a result of the explosive introduction of volcanic ejecta into the atmosphere. A base surge may carry air, water, and solid
debris outward from the volcano at the base of the vertical explosion column. Volcanic structures can take many forms. A few
of the smaller structures built directly around vents include cinder, spatter, and lava cones. Thick lavas may pile up over
their vents to form lava domes. Larger structures produced by low viscosity lava flows include lava plains and gently sloping
cones known as a shield volcanoes. A stratovolcano (also known as a composite volcano) is built of successive layers of ash
and lava. A volcano may consist of two or more cones side by side and is referred to as compound or complex. Sometimes a violent
eruption will partially empty the underground reservoir of magma. The roof of the magma chamber may then partially or totally
collapse. The resulting caldera may be filled by water. The volcanic structure tells us much about the nature of the eruptions.
Citation
- Title Volcanoes in Eruption - Set 1.
-
- creation Date
2015-11-10T05:28:11.280705
Resource language:
Processing environment:
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Metadata data stamp:
2018-08-06T19:38:24Z
Resource Maintenance Information
- maintenance or update frequency:
- notes: This metadata record was generated by an xslt transformation from a dc metadata record; Transform by Stephen M. Richard, based
on a transform by Damian Ulbricht. Run on 2018-08-06T19:38:24Z
Metadata contact
-
pointOfContact
- organisation Name
CINERGI Metadata catalog
-
- Contact information
-
-
- Address
-
- electronic Mail Address cinergi@sdsc.edu
Metadata language
eng
Metadata character set encoding:
utf8
Metadata standard for this record:
ISO 19139 Geographic Information - Metadata - Implementation Specification
standard version:
2007
Metadata record identifier:
urn:dciso:metadataabout:7ebed0ca-e743-4daa-ab7a-443a64290073
Metadata record format is ISO19139 XML (MD_Metadata)