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From : en.wikipedia.org




Lake Toba





Lake Toba is a lake, 100 km long and 30 km wide, and 505 m. (1,666 ft.) at its deepest point, in the middle of the northern part of the Indonesian island of Sumatra with a surface elevation of about 900 m (3,000 feet), stretching from 2.88° N 98.52° E to 2.35° N 99.1° E. It is the largest volcanic lake in the world.




The Toba eruption (the Toba event) occurred at what is now Lake Toba about 67,500 to 75,500 years ago. It had an estimated Volcanic Explosivity Index of 8 (described as "mega-colossal"), making it possibly the largest explosive volcanic eruption within the last twenty-five million years. Bill Rose and Craig Chesner of Michigan Technological University deduced that the total amount of erupted material was about 2800 cubic km (670 cubic miles) — around 2,000 km³ of ignimbrite that flowed over the ground and around 800 km³ that fell as ash, with the wind blowing most of it to the west. By contrast, the 1980 eruption of Mount St. Helens ejected around 1.2 cubic km of material, whilst the largest volcanic eruption in historic times, at Mount Tambora in 1815, emitted the equivalent of around 100 cubic kilometres of dense rock and created the "Year Without a Summer" as far away as North America.
The Toba eruption was the latest of a series of at least three
caldera-forming eruptions which have occurred at the volcano. Earlier calderas were formed around 700,000 and 840,000 years ago.[2]
To give an idea of its magnitude, consider that although the eruption took place in Indonesia, it deposited an ash layer approximately 15 cm (6 in) thick over the entire Indian subcontinent; at one site in central India, the Toba ash layer today is up to 6 m (20 feet) thick[3] and parts of Malaysia were covered with 9 m of ashfall.[4] In addition it has been calculated that 1010 metric tons of sulphuric acid was ejected into the atmosphere by the event, causing acid rain fallout.[5]

Landsat photo of Sumatra surrounding Lake Toba
The subsequent collapse formed a
caldera that, after filling with water, created Lake Toba. The island in the center of the lake is formed by a resurgent dome.
Though the year can never be precisely determined, the season can: only the
summer monsoon could have deposited Toba ashfall in the South China Sea, implying that the eruption took place sometime during the northern summer.[6] The eruption lasted perhaps two weeks, but the ensuing "volcanic winter" resulted in a decrease in average global temperatures by 3 to 3.5 degrees Celsius for several years. Greenland ice cores record a pulse of starkly reduced levels of organic carbon sequestration. Very few plants or animals in southeast Asia would have survived, and it is possible that the eruption caused a planet-wide die-off. There is some evidence, based on mitochondrial DNA, that the human race may have passed through a genetic bottleneck within this timeframe, reducing genetic diversity below what would be expected from the age of the species. According to the Toba catastrophe theory proposed by Stanley H. Ambrose of the University of Illinois at Urbana-Champaign in 1998, human populations may have been reduced to only a few tens of thousands of individuals by the Toba eruption.









The Sound of the Wind


Cibobos beach is located in Serang, Banten, West Java. To be more specific, it's
About 45 kilometers away from southern Serang and 70 kilometers from
Malimping, Bayah subdistrict, Lebak regency, Banten province. The word Cibobos
Comes from the Sundanese words Ci and Bobos. Ci means water and Bobos means
Fart. People around this beach call it so, because the waves that touch the rocks
Produce farting-like sounds.

A virgin beach with clean sand and fresh air creates a calm and comforting
Atmosphere. Wonderful reefs that jut out from the sea add to beautiful scenery of Hindia Ocean. Camping rock climbing and building sand castles are some of the fun. Activities that you can do together with your friends here. However if you don't like camping you can stay in a hostel for only 70000 to 120000 rupiah a day.


On they journey to Jakarta you can take the road that passes Pelabuhan Ratu
Sukabumi. Along the road between Malimping Bayah and Sukabumi you also can see other beautiful beaches such a Karangteraje Ciantir and Swarna. So what are you waiting for? Drop everything at once and go for one of those beautiful beaches. You won’t be sorry.

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