University of Tabriz Journal of Civil and Environmental Engineering 2008-7918 43 73 2014 02 20 Investigation on the Components of 2012 Twin Earthquakes of Azerbaijan along Principal Directions Investigation on the Components of 2012 Twin Earthquakes of Azerbaijan along Principal Directions 47 56 1257 FA Heidar Malekzadeh Hosein Ghaffarzadeh Journal Article 2014 05 03 Principal directions Ground motion Near-fault Uncorrelated axes Varzeghan-Ahar Earthquakes https://ceej.tabrizu.ac.ir/article_1257_d995b5aae551e4ac356a617f0dcb0a1a.pdf