Failed deep-drilling project yields data on high-temperature earthquake fault zone

Nature : The Alpine Fault, which lies at the boundary between the Australian and Pacific tectonic plates, is the largest seismic hazard on South Island, the larger of the two major islands in New Zealand. The fault averages a magnitude 8 earthquake every 330 years and last ruptured in 1717. In anticipation of its next major eruption, the Deep Fault Drilling Project was launched, which involves 90 scientists from 12 countries. Although the target drilling depth was 1300 m, the team got only as far as 893 m when a problem inserting a steel tube stopped the drilling. Nevertheless, the team was still able to extract rock samples near the fault and install a fiber-optic cable to act as a seismometer and measure temperature. As a result, the researchers have been able to collect some “very intriguing” data, and the project is proving to be an overall success. The team reported its findings this week at the fall meeting of the American Geophysical Union in San Francisco.