Kawah Ijen Volcano Kawah Ijen volcano is one of several volcanoes located in the 15km diameter Ijen Caldera in E Java, Indonesia. The caldera rim is still visible in places, but has been partially buried by Kawah Ijen, 2800m high Gunung Merapi (not to be confused with Merapi volcano near Yogyakarta), Gunung Rante and Gunung Pendil volcanoes. The caldera is today largely filled with coffee plantations. Kawah Ijen harbours a large warm acidic crater lake and an active sulphur mine. Due to its easy accessibility, turqoise lake and unique sulphur mining operation, the crater is regularly visited by tourists. The last recorded magmatic eruption of Kawah Ijen was in 1817. The eruption displaced the crater lake and resulted in inundation of several villages along the drainage route. Phreatic eruptions have been reported in 1796, 1917, 1936, 1950, 1952, 1993, 1994, 1999, 2000 (also minor ash emission), 2001, 2002 (with minor ash emission). The increasing frequency may reflect better reporting since the explosions are usually confined to the lake and cause little or no damage. http://www.photovolcanica.com/VolcanoInfo/Kawah%20Ijen/Kawah%20Ijen.html Photovolcanica.com Crater of Kawah Ijen volcano containing highly acidic lake and solfatara (bottom left). Sulphur Mining at Kawah Ijen Solfatara Pipe used to extract molten sulphur from the solfatara Small molten sulphur flow The sulphur mining operation consists of a number of pipes driven into the solfatara. Solfatara temperatures nearing 250 'C have been reported, although chemical analysis of solfatara gases suggests temperatures inside to be above 300'C. Condensation of volcanic gases saturated with elemental sulphur (formed by SO2 + 2H2S = 3S + 2H2O reaction) occurs as they cool during passage through the pipes. Molten sulphur trickles out of the end of the pipes, solidifying nearby as it cools further. The miners then break up the sulphur deposits and carry them out of the crater and, via the weighing station, to a nearby sugar refinery. Due to unprotected exposure to volcanic gases and loads of up to 100kg per trip, the life expectancy of the miners is low (not much over 30 years). The volcanic gases emitted are also responsible for the characteristics of the nearly 200m deep crater lake. Takano et al., 2004 (J. Volc. and Geotherm. Res. 135, p.299-329) extensively studied the crater lake. Injection rates of 340 tonnes/day of sulphur dioxide were calculated, accounting for the extreme acidity. Lake temperature and pH fluctuate and were reported at around 36'C and 0.1, respectively, near the surface in this study. Temperature and acidity change, along with visible lake surface changes such as colour fluctuations or local bubbling or upwelling can provide signs of increased activity along with seismic data which are regularly obtained. Also, observations by the mine workers can be taken into account, such as increased breathing difficulty or dizziness, suggesting changes in gas composition or levels. Interestingly, reports of birds falling into the lake (presumably due to intoxication by volcanic gases) have also been taken into account when assessing the risk of impending eruptions (Smithsonian Global Volcanism Program report 06/1997 (BGVN 22:06). Miners working in intense gases with merely handkerkiefs for protection. Miner carrying blocks of sulphur from the mine. Small sulphur flow emanating from pipe in sulphur mine ==================== http://www.kawahijen.com/ Kawah Ijen Tourism Service Indonesia is famous for hosting some of the world's most powerful volcanoes. Krakatoa, located on an island in the Sunda Strait between Java and Sumatra in Indonesia, is well known because of its 1883 eruption, which generated the loudest sound historically reported: it was distinctly heard even in the Australian city of Perth (approx. 1930 miles or 3100km), or the island of Rodrigues near Mauritius (approx. 3000 miles or 4800 km). 36,417 were killed, mostly by the tsunamis which followed the explosion. The 1883 eruption of Krakatoa was equivalent to an explosion of 200 megatons of TNT, about 13000 times the yield of the Little Boy bomb which devastated Hiroshima, Japan. Sea waves caused by the eruption were recorded as far as the English Channel. But perhaps the most amazing Indonesian volcano is Kawah Ijen (2,600m or 8,660ft tall), the "Green Crater" from western Java, which has a lake made of 36 million cubic meters representing a solution of sulfuric acid and hydrogen chloride, the most powerful existing acids. On the edges of the lake, the fumaroles (volcanic gas eruptions) depose 4 tonnes of sulfur daily. Such acid lakes are also found on the volcanoes Kusatsu-Shirane (Japan) and Poas (Costa Rica), but the Indonesian lake is by far the largest acid lake on Earth, having a maximum depth of 212m (706ft). These lakes result from the mix of rainfall water with gases coming from the depths of the volcano. The walls of the Kawah Idjen lake are light ocher, but the water has a turquoise color, with emerald reflexes. The temperature of the water is of 34o C, and sulfur bubbles float on the surface. The surroundings are covered by a sulfur powder. The smell is pungent and irritating, filled with sulfur dioxide. From place to place, sulfur pours at a temperature of 120o C, like bright red trails, which gradually solidify, turning lemon yellow. The lake contains 600,000 tonnes of hydrogen chloride, 550,000 tonnes of sulfuric acid, 200,000 tonnes of aluminium sulphate and 170,000 tonnes of iron sulphate. People from the neighboring area extract sulfur from the crater manually - an extremely hard work. To increase efficiency, the workers build tunnels of stone and undulated plates to channel the sulfur-rich fumaroles. The sulfur then leaks, cools down and solidifies inside these improvised channels, which are subsequently broken using metal piles. The recovered stuff contains 99% sulfur. The sulfur is made into pieces, loaded in baskets and transported on the men's back outside the crater. Once on the top, the workers must descend to the weighing place. In one day, a man can carry up to 360 kg (750 pounds) of sulfur. The daily production of the exploitation is just of 4 tonnes, a derisory quantity, if we consider the fact that the crater harbors 30,000 tonnes of sulfur. The sulfur is transported to Banjuwangi, 37 km (23 mi) away and it will be used for vulcanizing rubber or refining sugar. ======================== http://en.wikipedia.org/wiki/Ijen Wikipedia The Ijen volcano complex is a group of stratovolcanoes, in East Java, Indonesia. It is inside a larger caldera Ijen, which is about 20 kilometers wide. The Gunung Merapi stratovolcano is the highest point of that complex. (not to be confused with Mount Merapi, Central Java aka Gunung Merapi) West of Gunung Merapi is the Ijen volcano, which has a one-kilometer-wide turquoise-colored acid crater lake. The lake is the site of a labor-intensive sulfur mining operation, in which sulfur-laden baskets are carried by hand from the crater floor. Many other post-caldera cones and craters are located within the caldera or along its rim. The largest concentration of post-caldera cones forms an E-W-trending zone across the southern side of the caldera. The active crater at Kawah Ijen has an equivalent radius of 361 meters, a surface of 41 × 106 square meters. It is 200 meters deep and has a volume of 36 × 106 cubic meters. In 2008, explorer George Kourounis took a small rubber boat out onto the acid lake to measure its acidity. The pH of the sulfuric acid in the crater was measured to be 0.5. [1] Contents [hide] 1 Sulfur mining at Ijen 2 See also 3 References 4 External links [edit] Sulfur mining at IjenAn active vent at the edge of the lake is a source of elemental sulfur, and supports a mining operation. Escaping volcanic gasses are channeled through a network of ceramic pipes, resulting in condensation of molten sulfur. The sulfur, which is deep red in color when molten, pours slowly from the ends of these pipes and pools on the ground, turning bright yellow as it cools. The cooled material is broken into large pieces and carried out in baskets by the miners. Typical loads range from 70–100 kilograms, and must be carried to the crater rim approximately 200 meters above before being carried several kilometers down the mountain. Most miners make this journey twice a day. The miners are paid by a nearby sugar refinery by the weight of sulfur transported; as of September 2010 the typical daily earnings were equivalent to approximately $13.00 US. The miners often use insufficient protection while working around the volcano[2] and are susceptible to numerous respiratory complaints. ===================== http://www.boston.com/bigpicture/2010/12/kawah_ijen_by_night.html Boston.com Photographer Olivier Grunewald has recently made several trips into the sulfur mine in the crater of the Kawah Ijen volcano in East Java, Indonesia, bringing with him equipment to capture surreal images lit by moonlight, torches, and the blue flames of burning molten sulfur. Covered last year in the Big Picture (in daylight), the miners of the 2,600 meter tall (8,660ft) Kawah Ijen volcano trek up to the crater, then down to the shore of a 200-meter-deep crater lake of sulfuric acid, where they retrieve heavy chunks of pure sulfur to carry back to a weighing station. Mr. Grunewald has been kind enough to share with us the following other-worldly photos of these men as they do their hazardous work under the light of the moon. (30 photos total) A sulfur miner stands inside the crater of the Kawah Ijen volcano at night, holding a torch, looking towards a flow of liquid sulfur which has caught fire and burns with an eerie blue flame. (© Olivier Grunewald) Descending into the Kawah Ijen caldera, a one-kilometer-wide acidic crater lake lies in the middle. On its shore, the sulfur mining operation. (© Olivier Grunewald Steam and acidic gases emerge from fumaroles among yellowish chunks of sulfur and burning liquid sulfur on Kawah Ijen. (© Olivier Grunewald) # Flaming molten sulfur flows inside the volcanic crater. Sulfur will melt at just above 100 C (212 F), but the temperatures in the crater do not get high enough for spontaneous combustion - the fires are lit by the miner's dripping torches. (© Olivier Grunewald) # A miner chips away hunks of solid sulfur to take with him back to the mine office. (© Olivier Grunewald) # 6A sulfur deposit clings to the edge of an old barrel now embedded in sulfur inside Kawah Ijen. (© Olivier Grunewald) # Miners labor in hellish conditions to retrieve the sulfur - Photographer Olivier Grunewald describes the smell as overwhelming, requiring a gas mask for safety, which few of the miners possess. (© Olivier Grunewald) # Miners rest near a fire, holding long crowbars they use to pry the sulfur from the crater. (© Olivier Grunewald) # A formation caused by liquid sulfur flow inside the crater of Kawah Ijen. When molten, sulfur appears nearly blood red, as it cools, it becomes more and more yellow. (© Olivier Grunewald) # 10Molten sulfur burns after it drips from stone and ceramic pipes that have condensed the sulfuric gases from the volcano into a liquid, depositing it to cool and harden for later retrieval. (© Olivier Grunewald) # Lit by torches, miners chop away at the solid sulfur deposits, retrieving chunks they can carry back out. (© Olivier Grunewald) # A miner works on a block of sulfur, to fit it into the baskets used to carry the mineral out of the volcano. (© Olivier Grunewald) # Working close to condensation pipes a miner gathers sulfur from Kawah Ijen, molten sulfur burning blue in the background. (© Olivier Grunewald) # Miners carry heavy blocks of sulfur, preparing for their return trip. (© Olivier Grunewald) # 15Molten sulfur burns atop a solid sulfur deposit. Miners will extinguish the flames before they leave to prevent any loss of sulfur. (© Olivier Grunewald) # 16A miner begins his return trip with his heavy load of sulfur. (© Olivier Grunewald) # 19Miners begin their journey home, clouds of steam and gas behind them lit by moonlight, torchlight, and burning liquid sulfur. (© Olivier Grunewald) # 21A miner adjusts his load of sulfur blocks. (© Olivier Grunewald) # 22Miners carrying torches climb back up the wall of Kawah Ijen's crater, beginning their return trip with a 200 meter climb to the crater lip. (© Olivier Grunewald) # 23Looking back down on the mining operation inside the volcano, the burning sulfur, acidic lake and moonlit crater walls. (© Olivier Grunewald) # 25Inside the initial processing facility, the blocks of sulfur are broken down into much smaller bits. (© Olivier Grunewald) # 26The sulfur bits are then placed in large vessels above wood fires to be melted once again. (© Olivier Grunewald) # 28Some molten sulfur is channeled into other vessels. (© Olivier Grunewald) # 29The final step, spreading the liquid sulfur on slabs to cool into sheets, which, once hardened, will be shipped to local factories for use in vulcanizing rubber, bleaching sugar and other industrial processes. (© Olivier Grunewald) #