新托福阅读：Volcano borehole prompts safety doubts

活火山上钻孔直通火山中心保护意大利城市那不勒斯免遭灾难性火山喷发

Drilling deep into the heart of an active volcano might sound dangerous, but a team of scientists say that it could prove vital to protecting the Italian city of Naples from a potentially devastating eruption.

Early next month, researchers will begin to sample rocks and install underground sensors inside Campi Flegrei, a giant volcanic formation in southern Italy. They hope to learn where the magma is stored and what signs might precede an eruption. Campi Flegrei last erupted in 1538, and the ground in the area has been swelling for the past 40 years, leading to fears of another eruption within decades.

But critics say that the project is taking place too close to Naples and could lead to pollution, earthquakes or an explosion. The selected location "makes no sense," says Benedetto de Vivo, a professor of geochemistry at the University of Naples.

Campi Flegrei is thought to have formed 39,000 years ago, when a major eruption caused the ground to collapse in a 13-kilometer-wide area above a chamber of magma. The resultant bowl-shaped depression, known as a caldera, extends along the shore of the Gulf of Naples and is the site of a large number of craters and steaming fissures on land.

Scientists estimate that magma lies at least 7,000 meters below the surface of the caldera, but little is else is known about Campi Flegrei, or similar volcanoes. "Calderas are the only volcanoes that can cause truly catastrophic eruptions with global consequences, yet they are still poorly understood," says Giuseppe De Natale, the project's coordinator and a geophysicist at Italy's National Institute for Geophysics and Volcanology in Naples.

Deep heat

To learn more about the volcano, researchers are planning to drill a well in Bagnoli, a former industrial area near Naples and on the eastern part of the caldera. In the pilot phase of the project, starting in early October, De Natale's team will aim to reach a depth of 500 meters. The next phase, in which they will drill a 4,000-metre well at the same site, is to begin in spring 2011.