The 09 December 2024 Mw5.7 Parker Butte Earthquake: Orthogonal surface fracturing and associated ground disturbances near Yerington, Nevada, central Walker Lane

The Mw5.7 Parker Butte earthquake occurred on 09 December, 2024, ~24 km NNE of Yerington (western Nevada, USA) due to sinistral slip on an unmapped ENE-striking fault. Field reconnaissance and a drone survey were conducted within <1-8 days and ~1 month, respectively, after the earthquake. We observed a lack of surface rupture above the ENE-striking plane of the mainshock and most aftershocks, as well as surface fracturing along a NW-trending lineament orthogonal to the mainshock. Shaking effects included minor sediment failures, liquefaction features, and short-lived fracturing and refreezing features in ice on the Walker River and agricultural channels. Damage to infrastructure was minimal, only settlement and cracking of one bridge abutment fill prism. We estimate ground motions of up to 0.4 g and 23 cm/s. These observations provide valuable data about the effects of moderate magnitude earthquakes and highlight the importance of coordinated multidisciplinary geodetic, seismologic, and field geologic responses. The orthogonal faults indicated by the mainshock and the secondary surface fractures are part of a pattern in the region, where orthogonal faults have slipped in several historical earthquake sequences, establishing this as a common style of faulting within the complex network of faults that comprise the Walker Lane.