Towards an Earthquake Ground-Motion Database for Western and Central Australia

A ground-motion dataset from moderate-to-large magnitude earthquakes is compiled for earthquakes occurring in Proterozoic and Archean terranes of the Australian continental crust. Data, which are predominantly weak-motion velocity recordings, are compiled from low-sample-rate continuous waveform buffers and segmented high-sample-rate data (where available) recorded by the Australian National Seismograph Network (ANSN). Additional data are retrieved from various temporary deployments and, more recently, from the Incorporated Research Institutions for Seismology (IRIS) data centre. All raw data were first converted to a uniform miniSEED format from various binary and ASCII formats used over time. Corresponding instrument metadata is compiled in the standard FDSN StationXML format. The dataset currently contains 1497 earthquake recordings from 164 earthquakes occurring between 1990 and 2019. The magnitudes of earthquakes within the dataset range from MW 2.5 to 6.1 with hypocentral distances up to 1500 km. The time-series data are consistently processed to correct for the instrument response and to reduce the effect of background noise. A range of engineering parameters are calculated in time and frequency domains using the USGS’s ground-motion processing software, “gmprocess”. Numerous near-source recordings exceed peak accelerations of 0.10 g and range up to 0.66 g, while the maximum peak velocity of the dataset exceeds 27 cm/s. In spite of the limited number of seismic stations located throughout the Australian continental landmass, the dataset compiled herein will improve characterisation of ground-motion attenuation in the region and will provide an excellent supplement to ground-motion datasets collected in analogue seismotectonic regions worldwide. Presented at the 2021 Seismological Society of America (SSA) Annual Meeting