01-19-2014, 04:14 AM
Volcano Tamers; 1998
by Jim Wilson
Good News - Bad News
First the good news: Earth-tremor sensors and global communication networks make it possible to save millions of lives by predicting when volcanoes may erupt. Now the bad news: The people who live at the feet of active volcanoes don't seem to care.
Consider what happened last June when a mushroom cloud of smoke and ash rose above 17,890-ft. Popocatepetl, a volcano about 33 miles southeast of Mexico City. Troops dispatched to evacuate 30 villages near the peak came back empty-handed. Reportedly, the villagers refused to leave. They said that no one could be sure the volcano would swallow their homes. But if they left and it was a false alarm - as it turned out to be - bandits would plunder their possessions.
About a month later, on the West Indies island of Montserrat, die-hard residents refused to flee the path of the Soufriere Hill volcano until the British territorial government agreed to up its resettlement offer. With a half billion people endangered by active volcanoes, these reactions to hazard warnings are making an idea that once might have seemed absurd appear to be a stroke of genius: Move the lava. "You don't stop rain, you don't stop lava," says volcano tamer John P. Lockwood. "But you can divert them."
Diverting Lava Flow
When volcanoes erupt, Lockwood is often nearby. The former U.S. Geological Survey (USGS) geologist now makes a career of offering governments advice on keeping lava at bay. "Three methods have been used to attempt lava diversion," Lockwood says. Detonating explosives can disrupt lava flow. Construction of earthen walls can also deflect lava. And spraying large volumes of water can cool an advancing flow.
Experiments with aerial delivery of explosives date to a 1935 bombing mission in Hawaii organized by then-Lt. Col. George S. Patton Jr. The air-strike, by 1920s-era Keystone B-3 and B-4 bombers, was an attempt to disrupt a lava flow from Mauna Loa that was threatening the city of Hilo. Pele, the Hawaiian volcano goddess, apparently didn' t notice. Nor did she blink in 1942 when a second operation was mounted.
Bombs may not do the trick, but ground-based explosives certainly can. In 1996, the Italian army proved this by detonating 15,000 pounds of mining explosives to successfully block a lava tube leading from Mount Etna and threatening villages below. Mount Etna has also been the proving ground for earthen walls built to deflect flows. In this case, the walls were built by Italian army crews who were forced to work within 10 ft. of the 1800 [degrees] F molten rock.
The lava-diversion barrier Lockwood designed to protect the USGS Mauna Loa Observatory on the Big Island of Hawaii is based on similar design principles. It has yet to be tested. Controlling the flow of lava by spraying the brimstone with water has produced the most spectacular success of all. To get a closer look, we bought a ticket to Iceland.
Hell In Heimaey
Mid-December is not the time of year when they take the pretty pictures that adorn Iceland's travel brochures. This thought occurs to us as we look up from our breakfast of hot coffee and cold curried herring to see who's throwing gravel at the window. But it's just the rain. A storm is roiling in the North Atlantic. "It began on a day just like this," recalls Sveinbjorn Bjornsson, who in 1973 was a professor at the University of Iceland. Two seismic monitoring stations reported tremors. Telephone calls to the country' s two manned earthquake locations found nothing amiss.
On Heimaey, the only inhabited island in the Vestmannaeyjar archipelago - located 5 miles off Iceland's southern coast - there were more pressing problems than the earth moving. A storm was keeping 100 fishing boats in the harbor. In a country that puts a different fish on every coin, events like this don't make anyone happy. But at 2:30 am the next morning, those boats laying at anchor were the prettiest sight anyone had ever seen. For at precisely that moment, a 1 1/4-mile-long fissure opened less than a half mile from town. Against a back-drop of low-hanging clouds, it hurled 2200 [degrees] F lava 500 ft. into the sky. Ships that normally carried five quickly were packed with more than 100. Within six hours, all 5300 residents of the island were shuttled to the safety of the mainland.
As the public applauded the rescue, geologists began to worry. Images from American NOAA-2 and Landsat-1 satellites revealed a national disaster in the making. The lava had formed a 3000-ft.-wide 60-ft.- tall slug that, on its present track, would fill the harbor. To the quarter million who then lived in Iceland, Heimaey was as important as, say, Detroit is to Americans, It was one of the country' s top sources of foreign exchange. The idea of spraying the lava with seawater came from an observation made 10 years earlier when the newest of the Vestmannaeyjar islands, Surtsey, broke the surface after an underwater eruption.
Thorbjorn Sigurgeirsson, of the University of Iceland, had observed that sea spray falling on the lava appeared to solidify it from the top down, causing it to alter its path. Sveinbjorn takes a 3D map off the wall of his new office in the National Energy Authority in Reykjavik and recalls the course of the battle for Heimaey. It began with fire hoses, and then was fought with fire boats - and finally, giant industrial pumps. The water cooled the slug and slowed its rate of travel while steering its path into the open sea. This work took five months, during which 500 volcano tamers shuttled to Heimaey in groups of 75. Working back-to-back 14-hour days in conditions so hot their boots often caught fire, they slowly solidified the edge of the lava. It was only 500 ft. shy of closing the mouth of the harbor when the eruption ended on July 3.
The residents returned to an island that was 20% larger, had a more sheltered port and a landscape now graced with a pair of volcanoes. With most of the 2 million cu. yds. of volcanic debris that littered the streets, they lengthened the airport runway. Sveinbjorn came to the island often. It was time for the volcano tamers to collect war reparations. So for the next 10 years, an automatic system that watered the still-smoldering lava provided heat for all the homes on Heimaey. Lockwood and Sveinbjorn are realistic about what volcano tamers can and cannot do. At Heimaey, the port was saved, but at the expense of a portion of the city. Lockwood tends to be a bit philosophical about it all. "Nature," he observes, "always wins in the long run."
Popular Mechanics; March 1998
by Jim Wilson
Good News - Bad News
First the good news: Earth-tremor sensors and global communication networks make it possible to save millions of lives by predicting when volcanoes may erupt. Now the bad news: The people who live at the feet of active volcanoes don't seem to care.
Consider what happened last June when a mushroom cloud of smoke and ash rose above 17,890-ft. Popocatepetl, a volcano about 33 miles southeast of Mexico City. Troops dispatched to evacuate 30 villages near the peak came back empty-handed. Reportedly, the villagers refused to leave. They said that no one could be sure the volcano would swallow their homes. But if they left and it was a false alarm - as it turned out to be - bandits would plunder their possessions.
About a month later, on the West Indies island of Montserrat, die-hard residents refused to flee the path of the Soufriere Hill volcano until the British territorial government agreed to up its resettlement offer. With a half billion people endangered by active volcanoes, these reactions to hazard warnings are making an idea that once might have seemed absurd appear to be a stroke of genius: Move the lava. "You don't stop rain, you don't stop lava," says volcano tamer John P. Lockwood. "But you can divert them."
Diverting Lava Flow
When volcanoes erupt, Lockwood is often nearby. The former U.S. Geological Survey (USGS) geologist now makes a career of offering governments advice on keeping lava at bay. "Three methods have been used to attempt lava diversion," Lockwood says. Detonating explosives can disrupt lava flow. Construction of earthen walls can also deflect lava. And spraying large volumes of water can cool an advancing flow.
Experiments with aerial delivery of explosives date to a 1935 bombing mission in Hawaii organized by then-Lt. Col. George S. Patton Jr. The air-strike, by 1920s-era Keystone B-3 and B-4 bombers, was an attempt to disrupt a lava flow from Mauna Loa that was threatening the city of Hilo. Pele, the Hawaiian volcano goddess, apparently didn' t notice. Nor did she blink in 1942 when a second operation was mounted.
Bombs may not do the trick, but ground-based explosives certainly can. In 1996, the Italian army proved this by detonating 15,000 pounds of mining explosives to successfully block a lava tube leading from Mount Etna and threatening villages below. Mount Etna has also been the proving ground for earthen walls built to deflect flows. In this case, the walls were built by Italian army crews who were forced to work within 10 ft. of the 1800 [degrees] F molten rock.
The lava-diversion barrier Lockwood designed to protect the USGS Mauna Loa Observatory on the Big Island of Hawaii is based on similar design principles. It has yet to be tested. Controlling the flow of lava by spraying the brimstone with water has produced the most spectacular success of all. To get a closer look, we bought a ticket to Iceland.
Hell In Heimaey
Mid-December is not the time of year when they take the pretty pictures that adorn Iceland's travel brochures. This thought occurs to us as we look up from our breakfast of hot coffee and cold curried herring to see who's throwing gravel at the window. But it's just the rain. A storm is roiling in the North Atlantic. "It began on a day just like this," recalls Sveinbjorn Bjornsson, who in 1973 was a professor at the University of Iceland. Two seismic monitoring stations reported tremors. Telephone calls to the country' s two manned earthquake locations found nothing amiss.
On Heimaey, the only inhabited island in the Vestmannaeyjar archipelago - located 5 miles off Iceland's southern coast - there were more pressing problems than the earth moving. A storm was keeping 100 fishing boats in the harbor. In a country that puts a different fish on every coin, events like this don't make anyone happy. But at 2:30 am the next morning, those boats laying at anchor were the prettiest sight anyone had ever seen. For at precisely that moment, a 1 1/4-mile-long fissure opened less than a half mile from town. Against a back-drop of low-hanging clouds, it hurled 2200 [degrees] F lava 500 ft. into the sky. Ships that normally carried five quickly were packed with more than 100. Within six hours, all 5300 residents of the island were shuttled to the safety of the mainland.
As the public applauded the rescue, geologists began to worry. Images from American NOAA-2 and Landsat-1 satellites revealed a national disaster in the making. The lava had formed a 3000-ft.-wide 60-ft.- tall slug that, on its present track, would fill the harbor. To the quarter million who then lived in Iceland, Heimaey was as important as, say, Detroit is to Americans, It was one of the country' s top sources of foreign exchange. The idea of spraying the lava with seawater came from an observation made 10 years earlier when the newest of the Vestmannaeyjar islands, Surtsey, broke the surface after an underwater eruption.
Thorbjorn Sigurgeirsson, of the University of Iceland, had observed that sea spray falling on the lava appeared to solidify it from the top down, causing it to alter its path. Sveinbjorn takes a 3D map off the wall of his new office in the National Energy Authority in Reykjavik and recalls the course of the battle for Heimaey. It began with fire hoses, and then was fought with fire boats - and finally, giant industrial pumps. The water cooled the slug and slowed its rate of travel while steering its path into the open sea. This work took five months, during which 500 volcano tamers shuttled to Heimaey in groups of 75. Working back-to-back 14-hour days in conditions so hot their boots often caught fire, they slowly solidified the edge of the lava. It was only 500 ft. shy of closing the mouth of the harbor when the eruption ended on July 3.
The residents returned to an island that was 20% larger, had a more sheltered port and a landscape now graced with a pair of volcanoes. With most of the 2 million cu. yds. of volcanic debris that littered the streets, they lengthened the airport runway. Sveinbjorn came to the island often. It was time for the volcano tamers to collect war reparations. So for the next 10 years, an automatic system that watered the still-smoldering lava provided heat for all the homes on Heimaey. Lockwood and Sveinbjorn are realistic about what volcano tamers can and cannot do. At Heimaey, the port was saved, but at the expense of a portion of the city. Lockwood tends to be a bit philosophical about it all. "Nature," he observes, "always wins in the long run."
Popular Mechanics; March 1998