Large-N seismic arrays for applications from lithospheric structure to local surface processes

Brandon Schmandt¹

¹Department of Earth and Planetary Sciences, University of New Mexico, Alberquerque, US

Among the portable instruments used by natural source seismologists, cable-free seismographs containing geophones have seen rapidly expanded use in recent years for collecting continuous seismic data. Such rapidly deployable autonomous recording units are often referred to as ‘nodes’. They facilitate the deployment of large numbers of sensors to form ‘Large-N’ arrays suited to more wholistic investigation of wavefields rather than seismic motions at isolated sites. Some of the strengths and limitations nodal arrays will be illustrated through examples from ongoing collaborative research focused on tectonic, magmatic, and geomorphic processes operating across a wide range of scales. For crustal and lithospheric scale studies rapidly deployable and low impact nodal arrays can efficiently provide a higher frequency view of heterogeneous structures such as plate boundary interfaces and remnants of crustal growth by tectonic accretion. At finer scales of hundreds of meters nodal arrays can identify spatial and temporal variations in mechanical surface processes such as sediment transport in rivers and groundwater transport. Across the range of scales considered, nodal arrays open up increasing opportunities for synergy between natural and controlled source seismology projects. The presentation will use the examples above to illustrate some potential opportunities for ambitious future projects that leverage highly portable cable-free seismographs.