Brazil and volcano by Linda Potter
As I started this search I
turned first to Wikipedia and found only one volcano listed there. The following is the information I found
there when I put in Brazil and Volcanoes:
This
is a list of active and extinct volcanoes found mainly on Wikipedia even though
I went through the few listing I found on the web almost all of what I found was
linked to Wikipedia. From what research
I found it seems that Brazil has only one active volcano and that is Trindade. I posted cites that you can view pictures as they would not transfer when I copied and pasted from my windows program.
Trindade
600
1968
20°30′50″S
29°19′52″W / 20.514°S 29.331°W / -20.514; -29.331 (Trindade)
Holocene
(Wikipedia)
Volcanoes of the world and the number 9 and 41 are the
closest to Brazil -- The Trindale hotspot is marked 41 on map (Wikipedia).
The
Trindade hotspot is a working hypothesis supposing that the submarine volcanic
chain Vitória-Trindade, off the eastern coast of Brazil in the southern
Atlantic Ocean as a volcanic hotspot chain. It was considered that the supposed
hot-spot should be responsible for the creation of the east-west trending
Vitória-Trindade seamount chain, which includes the Trindade and Martim Vaz
archipelago at its easternmost end. Trindade, a small island in the
archipelago, is the hotspot's most recent eruptive center.
This
ideas was based on the geochemical data, especially of the highly
silica-undersaturated alklaine ultramafic rocks of the Trindade Island and
Martim Vaz Island. The isotopic data is OIB-type, which is favourable to the
hot-spot hypothesis. However, the volcanic chain direction is E-W and the
absolute motion vector of the South America Plate is NW. Therefore, the
volcanic chain cannot be a hot-spot chain. Recent research papers, as Skoletnev
et al. (2010) and Motoki et al. (2012), proposed that the hot mantle penetrated
horizontally along the Vitória-Trindade fracture zone which is present in the
lithospheric mantle. Because of the same reason, the Fernando de Noronha
Volcanic chain also is not a hot-spot chain. On the other hand, the NW-SE
magmatic alignments, such as the Cruzeiro do Sul Chain, Bahia Chain, and
Macau-Queimado, are considered to be hot-spot chains. (Wikipedia)
Trindade
and Martim Vaz (Portuguese: Trindade e Martim Vaz, [tɾĩˈdadʒi i mɐʁˈtʃĩ ˈvas]
or [tɾĩˈdadi i mɐʁˈtĩ ˈvas]) is an archipelago located about 1,200 kilometers
(740 mi) east of Vitória in the Southern Atlantic Ocean, belonging to the State
of Espírito Santo, Southeast Brazil. The archipelago has a total area of 10.4
km² (4.0 sq mi) and a population of 32 (Brazilian Navy personnel). The
archipelago consists of five islands and several rocks and stacks; Trindade is
the largest island, with an area of 10.1 km² (3.9 sq mi); about 49 km (30
miles) east of it are the tiny Martim Vaz islets, with a total area of 0.3 km²
(30 hectares).
The
islands are of volcanic origin and have rugged terrain. They are largely
barren, except for the southern part of Trindade. They were discovered in 1502
by Portuguese explorer Estêvão da Gama and stayed Portuguese until they became
part of Brazil at its independence. From 1890 to 1896, Trindade was occupied by
the United Kingdom until an agreement with Brazil was reached. During the
period of British occupation, Trindade was known as "South Trinidad."
more from WikipediaSnipview added this 414
days ago in Volcanoes of Brazil•Like•Comment• Share• FlagPress Enter to post
your comment Image via http://www.tralopia.com/en/place/no...Nova Iguaçu
Volcano
For wonderful pictures visit the following site ("Vulcão de Nova Iguaçu" in Portuguese) is
located in the state of Rio de Janeiro, Brazil, in an area of volcanic rocks at
the north-eastern border of the Mendanha massif. Klein and Vieira proposed the
site to be an extinct volcano with a volcanic cone, volcanic crater, and
volcanic bomb. Scientific journals have studied the volcanic geology of the
area, identifying the rocks of volcanic appearance as constituted of
subvolcanic intrusive rock bodies. The Nova Iguaçu volcano theory is now
extinct in academic communities, but the myth continues in sightseeing
promotion groups.
Recent
research revealed that volcanic eruptions did occur in the Nova Iguaçu region.
After the eruptions, an intense uplifting and consequent regional denudation
took place. The cones, craters, lavas, pyroclastic flow deposits, and volcanic
bombs have been washed away in the strong tropical erosion of this region,
exposing the underlying geologic structure. The Municipal Park is underlain by
the geologic bodies corresponding to the magma chamber (composed of syenite and
trachyte) and subvolcanic conduit (made up of pyroclastic rocks) of a depth of
3 kilometers, such as pyroclastic dikes. That is, no extinct volcano is present
at Nova Iguaçu. The outcrops are world-rare geological phenomena that expose
the underground geologic structures of the volcanic area.
The
Pico do Cabugi, also known as the Serra do Cabuji or Serrote da Itaretama, is
the only extinct volcano in Brazil which preserves its original form. It is 590
meters high and is located in the Cabugi Ecological State Park in the
municipality of Angicos in the state of Rio Grande do Norte.
Composed
mainly of basaltic alkaline intrusive rocks, this volcano was the result of a
major geological upheaval in the tertiary era which were responsible for
various volcanic cones in the rocky state of Rio Grande do Norte. They have
been dated using radioactive isotopes as the most recent of Brazilian igneous
rocks (± 19 million years). The presence of small xenoliths indicate that these
rocks have originated at a great depth (about 60 km).
The
researcher Lenine Pinto argues that when Brazil was first discovered by Pedro
Álvares Cabral, it was Pico do Cabugi that he first saw and not Monte Pascoal
(Wikipedia)
Taller
than Niagara Falls, twice as wide with 275 cascades spread in a horsehoe shape
over nearly two miles of the Iguazu River, Iguazú Falls are the result of a
volcanic eruption which left yet another large crack in the earth (About).
As you can see above one of the most amazing
sites are what a volcano left behind.
When we think about volcano’s we usually think of fire and
destruction. Which is true, just ask those
who have lost their home in Hawaii, however, sometimes something beautiful is
left behind. Crater Lake in Oregon is
one of the many lakes that have formed in volcanic craters. What about Yellowstone it is said to be the
results of a sleeping giant volcano.
Work Cited
About Travel, www.brazil.org.za/iguazu-falls.html
Trindade e Martim Vaz" by john.vergari - Arquipélago de Trindade e Martim Vaz. Licensed under CC BY 2.0 via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Trindade_e_Martim_Vaz.jpg#mediaviewer/File:Trindade_e_Martim_Vaz.jpg
Wikipedia,
Brazil and Volcanoes, http://tools.wmflabs.org/geohack/geohack.php?pagename=List_of_volcanoes_in_Brazil¶ms=20.514_S_29.331_W_type:mountain&title=Trindade,
http://www.snipview.com/search?q=Extinct_volcano
,
Very complete entry. Do not worry about the pictures.With your links,w e can all go and check them out! Hope you are enjoying discovering Brazil..
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