Frequency content and attenuation laws for “Sierras Pampeanas” earthquakes and their direct implications on the seismic assessment for life extension of Embalse NPP

MARTINO, R. D.; BONALUMI, A.A.; ROCCA, R.J.

Toronto, Canadá

Conferencia; 19th International Conference on Structural Mechanics in Reactor Technology. SMiRT 19; 2007

Sierras Pampeanas (Pampean Ranges) are a Rocky Mountains Laramide type, located between 28º and 33º S. They are broken Andean foreland blocks, built as a consecuence of the flat-lying orientation of the Nazca subducting plate. The Sierra Chica range is a mountain block rotated along the Sierra Chica fault, a main continental feature that has neogene thrust displacement measured in several location of its trace. Embalse NPP is located very close to the Sierra Chica fault trace (less than 1 km). Historical and instrumental records show moderate seismicity (M < 6.5) for the Sierras Pampeanas. Since the early 1980´s when Embalse started its operations, some acceleration records have been registered in the Sierras Pampeanas region. They are analyzed and compared with the WES and CEUS earthquake patterns. Some of the implications on the assessment for life extension of Embalse NPP, are presented.