|
|
|
 |
|
|
Information
Lombok Rinjani Mountain
Indonesia,3726m
Mount Rinjani or Gunung Rinjani
is an active volcano in
Indonesia on the island of
Lombok. Administratively the
mountain is in the Regency of
North Lombok, West Nusa Tenggara
(Indonesian: Nusa Tenggara
Barat, NTB). It rises to 3,726
metres (12,224 ft), making it
the second highest volcano in
Indonesia.
On the top of the volcano is a
6-by-8.5-kilometre (3.7 by 5.3
mi) caldera, which is filled
partially by the crater lake
known as Segara Anak or Anak
Laut (Child of the Sea) due to
blue color of water lake as Laut
(Sea). This lake is
approximately 2,000 metres
(6,600 ft) above sea level and
estimated to be about 200 metres
(660 ft) deep; the caldera also
contains hot springs. Sasak
tribe and Hindu people assume
the lake and the mount are
sacred and some religious
activities are occasionally done
in the two areas. On 31 October
2015, Mount Rinjani started
erupting again.
Geography
Lombok is one of the Lesser
Sunda Islands, a small
archipelago which, from west to
east, consists of Bali, Lombok,
Sumbawa, Flores, Sumba and the
Timor islands; all are located
at the edge of the Australian
continental shelf. Volcanoes in
the area are formed due to the
action of oceanic crusts and the
movement of the shelf itself.
Rinjani is one of at least 129
active volcanoes in Indonesia,
four of which belong to the
volcanoes of the Sunda Arc
trench system forming part of
the Pacific Ring of Fire – a
section of fault lines
stretching from the Western
Hemisphere through Japan and
South East Asia. The islands of
Lombok and Sumbawa lie in the
central portion of the Sunda
Arc. The Sunda Arc is home to
some of the world's most
dangerous and explosive
volcanoes. The eruption of
nearby Mount Tambora on Sumbawa
is known for the most violent
eruption in recorded history on
15 April 1815, with a scale 7 on
the VEI.
The highlands are forest clad
and mostly undeveloped. The
lowlands are highly cultivated.
Rice, soybeans, coffee, tobacco,
cotton, cinnamon, cacao, cloves,
cassava, corn, coconuts, copra,
bananas and vanilla are the
major crops grown in the fertile
soils of the island. The slopes
are populated by the indigenous
Sasak population. There are also
some basic tourist related
activities established on
Rinjani primarily in or about
the village of Senaru.
Rinjani volcano on the island of
Lombok rises to 3,726 metres
(12,224 ft), second in height
among Indonesian volcanoes only
to Sumatra's Kerinci volcano.
Rinjani has a steep-sided
conical profile when viewed from
the east, but the western side
of the compound volcano is
truncated by the 6 x 8.5 km,
oval-shaped Segara Anak caldera.
The western half of the caldera
contains a 230-metre-deep lake
whose crescentic form results
from growth of the post-caldera
cone Barujari at the eastern end
of the caldera. Color infrared
view of Rinjani Volcano on
Lombok Island, May 1992. Lombok
Strait and Bali are on the top,
Alas Strait and Sumbawa Island
are on the bottom.
Geologic summary
On the basis of plate tectonics
theory, Rinjani is one of the
series of volcanoes built in the
Lesser Sunda Islands due to the
subduction of Indo-Australian
oceanic crust beneath the Lesser
Sunda Islands, and it is
interpreted that the source of
melted magma is about 165–200
kilometres (103–124 mi) depth.
The geology and tectonic setting
of Lombok (and nearby Sumbawa)
are described as being in the
central portion of the Sunda
Arc. The oldest exposed rocks
are Miocene, suggesting that
subduction and volcanism began
considerably later than in Java
and Sumatra to the west, where
there are abundant volcanic and
intrusive rocks of Late Mesozoic
age. The islands are located on
the eastern edge of the Sunda
shelf, in a zone where crustal
thickness is apparently rapidly
diminishing, from west to east.
The seismic velocity structure
of the crust in this region is
transitional between typical
oceanic and continental profiles
and the Mohorovičić
discontinuity (Moho) appears to
lie at about 20 kilometres (12
mi) depth. These factors tend to
suggest that there has been
limited opportunity for crustal
contamination of magmas erupted
on the islands of Lombok and
Sumbawa. In addition, these
islands lie to the west of those
parts of the eastern-most Sunda
and west Banda arcs where
collision with the Australian
plate is apparently progressing.
The volcano of Rinjani is 165 to
190 kilometres (103–118 mi)
above the Benioff Zone. There is
a marked offset in the line of
active volcanoes between the
most easterly Sumbawa volcano
(Sangeang Api) and the line of
active volcanoes in Flores. This
suggests that a major
transcurrent fault cut across
the arc between Sumbawa Island
and Flores. This is considered
to be a feature representing a
major tectonic discontinuity
between the east and west Sunda
Arcs (the Sumba Fracture).
Further, a marked absence of
shallow and intermediate
earthquake activity in the
region to the south of Lombok
and Sumbawa is a feature
interpreted to represent a
marked break in the Sunda Arc
Zone. Faulting and folding
caused strong deformation in the
eastern part of Lombok Basin and
is characterized by block
faulting, shale diapirs and mud
volcano. (source by
https://en.wikipedia.org/wiki/Mount_Rinjani)
Lombok Rinjani Trekking
Fax Number : 0370 - 692035
Whatshapp : +62
081339522032
Mobile Number : +62
081803684982
Website :
http://www.lombokrinjani.com
e-mail address :
lombokrinjani@gmail.com
Jl.Tenggiri no.15 BTN
Green Valley Senggigi - Lombok, Indonesia
|
|
|
|
| |
|
 |
 |
|
|
|
|
