More than a year after a magnitude-8 earthquake rocked southern Peru, a team of Peruvian and French scientists launched a satellite-controlled robotic glider submarine Thursday off the coast of Pisco to study the deep ocean floor.
Glider submarines, a barely decade-old technology, are autonomous underwater vehicles that can swoop and soar deep beneath the ocean waves on extended ocean sampling missions lasting from hours to weeks or months, and to thousands of kilometers of range.
The submarine robot, which uses buoyancy-based propulsion to rise and fall through the ocean as it aerodynamicly glides forward, was launched by a team of scientists sponsored by France’s LOCEAN and LEGOS labs and Institute for Research and Development (IRD) as well as the Geophysical Institute of Peru and the Andean country’s Ocean Institute, or Imarpe.
The glider, which is to travel as deep as 200 meters, or 657 feet, has been fitted with instruments to measure ocean temperature, salinity, oxigen concentration, currents, chlorophyll fluorescence as well as turbidity and sediment concentrations.
The information it gathers, which is transmitted to computers via a built-in satellite phone when the glider periodically surfaces, will be used to develop high-resolution numerical ocean models. The research team also hopes to improve the performance of actual ocean simulation models, which are used, among other things, to measure seafloor plate tectonic motions.
At the site of the August 15 2007 Pisco earthquake, which destroyed three-quarters of the city centre and killed approximately 500 people, the Nazca and South American plates constantly collide and slide over and under each other.
This process, called subduction, is responsible for small offshore earthquakes as well as more than 60 moderate to large earthquakes annually.
But, subduction is also responsible for Peru’s largest and most destructive earthquakes.
The August 15 shock originated in the ocean floor near the source of two other destructive magnitude 8 earthquakes in 1908 and 1974. And, subduction of the Nazca and South American plates triggered Peru’s worst earthquake, a magnitude 9 that occurred in 1868. The quake killed over 25,000 throughout the Pacific Basin and triggered catastrophic tsunamis that travelled as far as New Zealand.
