In June 2010, a team of scientists and intrepid explorers stepped onto the shore of the lava lake boiling in the depths of Nyiragongo Crater, in the heart of the Great Lakes region of Africa. The team had dreamed of this: walking on the shores of the world's largest lava lake. Members of the team had been dazzled since childhood by the images of the 1960 documentary "The Devil's Blast" by Haroun Tazieff, who was the first to reveal to the public the glowing red breakers crashing at the bottom of Nyiragongo crater. Photographer Olivier Grunewald was within a meter of the lake itself, giving us a unique glimpse of its molten matter. (The Big Picture featured Olivier Grunewald's arresting images of sulfur mining in Kawah Ijen volcano in East Java, Indonesia, in a December 2010 post.) -- Paula Nelson
The view from the volcano’s rim, 11,380 feet above the ground. At 1,300 feet deep, the lava lake has created one of the wonders of the African continent.
The permanent lava lake of the Nyiragongo is the biggest in the world, an estimated 282 million cubic feet of lava. In 1977 and 2002, the lava lake breached the crater, destroying a large part of the city of Goma in the Democratic Republic of Congo. #
At the surface of the lake, bubbles of gas explode. The surface is permanently churned by fury from the earth's crust.
Even though the lava lake often overflows, the seven members of the expedition yearn to walk its shores. c #
Mount Nyiragongo is the most active of the eight volcanoes forming the Virunga range. #
At the beginning of the descent to the second terrace, falling rocks are a major risk. The gas often blinds the climbers. #
The expedition members need to tote a total of 1,300 pounds of equipment, food, and water -- enough for two days. The base camp is set up about 400 feet above the lava lake. #
To prepare for the expedition, members have undergone four months of training. #
Jacques Barthelemy, a mountaineer and veteran of Nyiragongo, uses a rope to bring bags of equipment to the second terrace
Volcanic gases heat the base camp. Members often need to don gas masks for sleeping.
Using a laser telemeter, a member measures the changing size of the lava lake.
Dario Tedesco, a volcanologist, collects gas to learn more about the volcanic activity
The hot gas condenses into a small puddle. Scientists say it is vital to take measurements in the crater over several periods in order to better understand the volcano and determine when it could erupt.
At night, the base camp is illuminated by the light of the lava lake
The goal of the expedition is to reach the rim of the lava lake. Nobody has previously survived such an encounter
Members of the team keep in contact through radio and relay data about the lava lake's activities and the direction of the gases
Climbers must determine the best method for descent.
Pierre-Yves Burgi collects gas near the bottom of the crater. The samples will be studied by Dario Tedesco, who was recently named as the head of Natural Risk Analysis and Prevention with the United Nations Office for Project Services
Bubbles of gas explode at the surface of the lava lake
Franck Pothé approaches the lava. For such a close encounter, the wind must be at his back, pushing the heat away. Pothé is constantly informed of the swirling winds via radio contact with other members
Marc Caillet is the first member of the team to reach the lake’s rim.
Olivier Grunewald prepares his photographic equipment to protect it from temperatures that can reach 1,300 degrees.
Approaching 282 million cubic feet of lava requires extensive protections
Encumbered by equipment, Olivier Grunewald must be guided by radio to where he can place his hands and feet.
Grunewald, on the lava lake’s first close-up: "I was so overwhelmed by the spectacle of this surface and trying to take pictures, I had no idea of time, of heat ... suddenly the radio told me that it was time to go, the activity being too close.’
A major risk is the frequent overflows of the lake. Members surveying the lake from the second terrace help alert others to any threatening lava movements.
At dawn, the light becomes magic, but gases could cover the bottom of the crater in a matter of seconds. #
An overflow starts at the beginning of the night. Year after year, the lava reaches higher along the crater walls, until another breach or an eruption empties the vessel. The goal of the expedition is to increase volcanologists’ knowledge and ability to predict such an event and prevent another disaster.