A New Strategy to Compare Inverted Rupture Models Exploiting the Eigenstructure of the Inverse Problem

Finite-fault-slip inversions provide crucial information on earthquake rupture phenomena. Many slip-inversion methods exist and differ in how the rupture model is parameterized and which regularizations or constraints are applied (e.g., Ide, 2007, and references therein). Some methods are utilized even routinely for large earthquakes and published online (e.g., the U.S. Geological Survey website http://earthquake.usgs.gov/, last accessed August 2015). However, the slip-inversion results obtained by various authors for the same event may differ (e.g., Clévédé et al., 2004). There is currently no consensus about which slip-inversion method is preferable, and there are concerns about the reliability of the inferred source models due to the nonuniqueness or ill conditioning of the inverse problem (Hartzell et al., 2007; Zahradník and Gallovič, 2010; Gallovič and Zahradník, 2011; Shao and Ji, 2012). Therefore, slip inversion is still a subject of active research.