High-resolution surface faulting from the 1983 Idaho Lost River Fault Mw 6.9 earthquake and previous events

Simone Bello,Tyler Scott,Federica Ferrarini,Francesco Brozzetti,Daniele Cirillo,J Ramón Arrowsmith,Chelsea P Scott,Giusy Lavecchia,Rita De Nardis

doi:10.1038/s41597-021-00838-6

Simone Bello, Tyler Scott + Show 7 more

Open Access

https://doi.org/10.1038/s41597-021-00838-6

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Abstract

We present high-resolution mapping and surface faulting measurements along the Lost River fault (Idaho-USA), a normal fault activated in the 1983 (Mw 6.9) earthquake. The earthquake ruptured ~35 km of the fault with a maximum throw of ~3 m. From new 5 to 30 cm-pixel resolution topography collected by an Unmanned Aerial Vehicle, we produce the most comprehensive dataset of systematically measured vertical separations from ~37 km of fault length activated by the 1983 and prehistoric earthquakes. We provide Digital Elevation Models, orthophotographs, and three tables of: (i) 757 surface rupture traces, (ii) 1295 serial topographic profiles spaced 25 m apart that indicate rupture zone width and (iii) 2053 vertical separation measurements, each with additional textual and numerical fields. Our novel dataset supports advancing scientific knowledge about this fault system, refining scaling laws of intra-continental faults, comparing to other earthquakes to better understand faulting processes, and contributing to global probabilistic hazard approaches. Our methodology can be applied to other fault zones with high-resolution topographic data.

Highlights

Background & SummaryIn the past 40 years, numerous moderate-to-large intra-continental extensional earthquakes (Mw 6–7) have generated complex surface ruptures along primary and secondary synthetic and antithetic splay faults
We provide the mapped traces as shapefiles, three tables that provide geometric information on the Coseismic surface ruptures (CoRs) and Quaternary fault scarp (Qfs) of the areas shown in Fig. 1, vertical separations (VS) measurements, methodology, topographic profiles, and quality parameters stored in Pangaea[34]
Our data are critical for informing paleoseismic, tectonic geomorphology and structural geologic investigations of the Lost River Fault (LRF), as well as for characterizing probabilistic fault displacement hazard analysis[29], the effect of geometric discontinuities on rupture extent, and slip-length scaling in large earthquakes[35,36,37,38]

Summary

Background & Summary

In the past 40 years, numerous moderate-to-large intra-continental extensional earthquakes (Mw 6–7) have generated complex surface ruptures along primary and secondary synthetic and antithetic splay faults. We provide the mapped traces as shapefiles, three tables that provide geometric information on the CoRs and Qfs of the areas shown, VS measurements, methodology, topographic profiles, and quality parameters stored in Pangaea[34]. This database provides new high-resolution information on recent-ground-rupturing earthquakes along the LRF, a major active extensional fault. Our data are critical for informing paleoseismic, tectonic geomorphology and structural geologic investigations of the LRF, as well as for characterizing probabilistic fault displacement hazard analysis[29], the effect of geometric discontinuities on rupture extent, and slip-length scaling in large earthquakes[35,36,37,38]. Our methodology advances systematic approaches for measuring fault scarp profiles from the growing archive of high-resolution topography

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