Preservation of amorphous ultrafine material: A proposed proxy for slip during recent earthquakes on active faults.

ABSTRACT: The criteria for designating an "Active Fault" not only are important for understanding regional tectonics, but also are a paramount issue for assessing the earthquake risk of faults that are near important structures such as nuclear power plants. Here we propose a proxy, based on the preservation of amorphous ultrafine particles, to assess fault activity within the last millennium. X-ray diffraction data and electron microscope observations of samples from an active fault demonstrated the preservation of large amounts of amorphous ultrafine particles in two slip zones that last ruptured in 1596 and 1999, respectively. A chemical kinetic evaluation of the dissolution process indicated that such particles could survive for centuries, which is consistent with the observations. Thus, preserva

SUBMITTER: Hirono T 

PROVIDER: S-EPMC5101524 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature