According to the US Geological Survey , the earthquake was caused by sections of the earth rubbing alongside each other at vertical , or nearly vertical , fracture points in what is known as a strike-slip fault .
Servicio Geológico de Estados Unidos ( USGS ) ukan yatiyäwiparjamax uka uraq khathatix pä placas terrestres ukan muqthaptäwipatw utjaw sasinw yatiyi .