Bunaken

Bunaken: National Marine Park and Diving

Bunaken is an island of 8 km², part of the Bunaken National Marine Park. Bunaken is located at the north of the island of Sulawesi, Indonesia. It belongs administratively to the municipality of Manado. Scuba diving attracts many visitors to the island.


Bunaken National Park extends over an area of 890.65 km² of which only 3% is terrestrial, including Bunaken Island, as well as the islands of Manado Tua, Mantehage, Nain and Siladen.

The waters of Bunaken National Marine Park are up to 1,566 m deep in Manado Bay, with temperatures ranging between 27 to 29 °C. It has a high diversity of - corals, fish, echinoderms or sponges. Notably, 7 of the 8 species of giant clams that occur in the world, occur in Bunaken.

Bunaken Island

Oceanic currents may explain, in part, why Bunaken National Marine Park has such a high level of biodiversity. Northeasternly currents generally sweep through the park but abundant counter currents and gyros related to lunar cycles are believed to be a trap for free swimming larvae. This is particularly true on the south side of the crescent-shaped Bunaken Island, lying in the heart of the park.

Manado Tua

A snorkeler or diver in the vicinity of Lekuan or Fukui may spot over 33 species of butterfly fish and numerous types of groupers, damsels, wrasses and gobies. The gobies, smallish fish with bulging eyes and modified fins that allow them to attach to hard surfaces, are the most diverse but least known group of fish in the park.

Diving in Bunaken National Marine Park

- Bunaken

DANAU TOBA

THE LARGEST VOLCANIC LAKE IN THE WORLD

Lake Toba (Indonesian: Danau Toba) is a lake and supervolcano, 100 kilometres long and 30 kilometres wide, and 505 metres (1,666 ft) at its deepest point. Located in the middle of the northern part of the Indonesian island of Sumatra with a surface elevation of about 900 metres (2,953 ft), the lake stretches from 2°53′N 98°31′E / 2.88°N 98.52°E / 2.88; 98.52 to 2°21′N 99°06′E / 2.35°N 99.1°E / 2.35; 99.1. It is the largest volcanic lake in the world.


In addition, it is the site of a supervolcanic eruption that occurred about 74,000 years ago, a massive climate-changing event. The eruption is believed to have had a VEI intensity of 8. This eruption is believed to have been the largest anywhere on Earth in the last 25 million years.

According to the Toba catastrophe theory to which some anthropologists and archeologists subscribe, it had global consequences, killing most humans then alive and creating a population bottleneck in Central Eastern Africa and India that affected the genetic inheritance of all humans today.

Geology

The Toba caldera complex in Northern Sumatra, Indonesia consists of four overlapping volcanic craters that adjoin the Sumatran "volcanic front". The youngest and fourth caldera is the world's largest Quaternary caldera (100 by 30 kilometres) and intercepts the three older calderas.

An estimate of 2500-3000 cubic kilometres of dense-rock equivalent pyroclastic material, known the Youngest Toba tuff, was blasted from the youngest caldera during one of the largest single eruptions in geologic history. Following the "Youngest Toba tuff eruption", a typical resurgent dome formed within the new caldera, joining two half-domes separated by a longitudinal graben.

There are at least four cones, four stratovolcanoes and three craters visible in the lake. The Tandukbenua cone on the NW edge of the caldera is relatively lacking in vegetation, suggesting a young age of only several hundred years. Also, the Pusubukit volcano on the south edge of the caldera is solfatarically active.

The Eruption

The Toba eruption (the Toba event) occurred at what is now Lake Toba about 67,500 to 75,500 years ago. The Toba eruption was the latest of a series of at least three caldera-forming eruptions which have occurred at the volcano, with earlier calderas having formed around 700,000 and 840,000 years ago. The last eruption 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 have deduced that the total amount of erupted material was about 2,800 km3 (670 cu mi) — around 2,000 km3 (480 cu mi) of ignimbrite that flowed over the ground, and around 800 km3 (190 cu mi) that fell as ash, with the wind blowing most of it to the west. The pyroclastic flows of the eruption destroyed an area of 20,000 square kilometres (7,722 sq mi), with ash deposits as thick as 600 metres (1,969 ft) by the main vent.

The People

Most of the people who live around Lake Toba are ethnically Bataks. Traditional Batak houses are noted for their distinctive roofs (which curve upwards at each end, as a boat's hull does) and their colorful decor.

Flora and Fauna

Lake Toba offers a nurturing environment for fish such as the tilapia mossambica, aplocheilus pachax, lebistes reticulatus, osphronemus goramy, trichogaster trichopterus, channa striata, chana gachua, clarias batrachus, clarias nieuhofi, clarias. sp., nemachilus fasciatus, cyprinus carpio, puntius javanicus, puntius binotatus, osteochilus nasselti, lissochilus sp., labeobarbus sora, and rasbora sp.

Many other types of plants and animals live within the boundaries of Lake Toba. Flora organisms include various types of phytoplankton, emerged macrophytes, floating macrophytes, and submerged macrophytes. Fauna include several variations of zooplankton and benthos.

- DANAU TOBA

KELIMUTU MOUNTAIN

Lakes in Three Colors

Kelimutu is a volcano, close to the town of Moni in central Flores Island of Indonesia containing three summit crater lakes of varying colors. Tiwu Ata Mbupu (Lake of Old People) is usually blue and is the westernmost of the three lakes.


The other two lakes, Tiwu Nuwa Muri Koo Fai (Lake of Young Men and Maidens), and Tiwu Ata Polo (Bewitched or Enchanted Lake) are separated by a shared crater wall and are typically green or red in color, respectively. The lake colors do vary on a periodic basis. Subaqueous fumaroles are the probable cause of active upwelling that occurs at the two eastern lakes.

The lake have been a source of minor phreatic eruptions in historical time. The summit of the compound 1639-m-high Kelimutu volcano is elongated two km in a WNW-ESE direction; the older cones of Kelido and Kelibara are located respectively three km to the north and two km to the south. The scenic lakes are a popular tourist destination.


Keli Mutu is also of interest to geologists because the three lakes are different colors yet reside at the crest of the same volcano.

The closest airports are Maumere, and Ende. There are regular flights to Maumere from Bali. The drive from Maumere to Moni, the town at the base of Keli Mutu, takes about 3 hours.

- KELIMUTU MOUNTAIN