Tuesday, December 23, 2008
First human contact with magma
According to a report in National Geographic News, the drilling crew cracked through rock layers deep beneath Hawaii and touched magma in its natural environment.
The find was made 1.5 miles (2.5 kilometers) underground during exploratory drilling for geothermal energy.
The crew hit something unusual during routine operations at the Puna Geothermal Venture, owned by Ormat Technologies, Inc., of Reno, Nevada.
When the workers tried to resume drilling, they discovered that magma had risen about 25 feet (8 meters) up the pipe they”d inserted.
The rock solidified into a clear glassy substance, apparently because it chilled quickly after hitting groundwater.
“This is an unprecedented discovery,” said Bruce Marsh, a volcanologist from Johns Hopkins University in Maryland, who will be studying the find. ”Normally, volcanologists have to do “postmortem studies” of long-solidified magmas or study active lava during volcanic eruptions,” he said.
But this time, they”d found magma in its natural environment, something Marsh described as nearly as exciting as a paleontologist finding a dinosaur frolicking on a remote island.
Scientists had long known that magma chambers must lie in the vicinity of the drill site.
The drilling was being conducted for an existing geothermal power plant built to harvest heat from the world’’s most active volcanic zone, Kilauea volcano, which has been spewing lava continuously since 1983.
According to Don Thomas, a geochemist from the University of Hawaii’’s Center of the Study of Active Volcanoes, it was just a matter of time until some drilling operation there struck hot magma.
In addition, researchers found that the magma is made of dacite, a type of rock that’’s a precursor to granite, rather than the basalt that forms most of Hawaii.
Volcanologist Marsh is excited by the prospects for further study.
“This is just the tip of the iceberg,” he said. “We don”t know where it’’s going to lead, but it’’s a golden opportunity,” he added.
It might even be possible to do experiments inside the magma.
“This could be the first magma observatory in the Earth,” Marsh said. “This is a singular event of first contact with inner Earth, where magma lives,” he added.
With an estimated temperature of 1,050 degrees Celsius, the magma is also valuable as a high-quality heat source for geothermal energy production.