Surface rupture and distributed deformation revealed by optical satellite imagery: The intraplate 2016 Mw 6.0 Petermann Ranges earthquake, Australia

Ryan Gold1, Dan Clark2, William Barnhart3, Tamarah King4, Mark Quigley4, Richard Briggs1 (1USGS; 2Geoscience Australia; 3Department of Earth and Environmental Sciences, University of Iowa; 4School of Earth Sciences, University of Melbourne)

Geophysical Research Letters, 2019


As described in a previous post, we got out to the 2016 Petermann surface rupture within ~ 8 days. The only data at that point was a magnitude, some aftershocks, a focal mechanism, an ever-moving epicentre (seismologists were still refining their locations), and some cracking along a dirt road observed by Dan Clark (Geoscience Australia) during deployment of temporary seismometers. After only a few days we were forced out of the field due to rain, but thanks to a 20km hike in the wrong direction, we knew the fault was NE dipping and located at the cracking observed by Dan.

Examples of the road cracking in question

As we sat waiting for the roads to dry out so we could finally go and look for the rupture, colleagues in the USA and at Geoscience Australia were busy analyzing post-earthquake satellite data. InSAR across the Petermann earthquake location became available, and showed a clear ~21 km long fault rupture at the surface, with up to 1 m of offset in the direction of the satellite. This was the first new information to reach us, and supported our field observations.

InSAR interferogram from Geoscience Australia

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Surface-rupturing historical earthquakes in Australia and their environmental effects: new insights from re-analyses of observational data


Tamarah R. King1, Mark Quigley1, Dan Clark2 (1School of Earth Sciences, University of Melbourne; 2Geoscience Australia)

Geosciences, 2019 


From May – July 2019 I didn’t really see my friends, I postponed my birthday, and I barely spoke to family. I was completely focused on writing a review paper of historic Australian surface rupturing earthquakes.

I’d spent years coming back to these eleven surface ruptures in QGIS wondering why they didn’t seem to resemble ‘faults’ as I thought they should (i.e. planar structures). At some point I’d digitised historic maps of the ruptures and some of the historic offset data, with the idea of trying to find answers to why they had such odd shaped surface ruptures. But my research was focused on other things, so I put these ideas and questions aside. Then in May 2019, My supervisor Mark was invited to contribute to a special edition on environmental effects, and suggested I could collate data from Australian surface ruptures. The deadline was two months away. Seemed easy?

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Earthquake environmental effects produced by the Mw 6.1, 20th May 2016 Petermann earthquake, Australia

Tamarah R. King1, Mark C. Quigley, 1Dan Clark2 (1School of Earth Sciences, University of Melbourne; 2Geoscience Australia)

Tectonophysics, 2018


In May 2016 I was ~ 4 months into my PhD and preparing to leave for field-work in remote central Australia. Six days before my planned departure, the Mw 6.1 Petermann earthquake occurred just 300 km west of my planned field site. My partner and I drove the 2,200 km from Melbourne in three days, picked up Mark Quigley at the Yulara (Uluru/Ayers Rock) airport, and drove the final 150 km of single lane dirt track to the epicentre location.

At that point, we didn’t know if there was a surface rupture. But as we neared the epicentre, we noticed rock outcrops with clear fresh damage, and cracks along the road increasing in frequency. We camped on the approximate epicentre location and (based on the focal mechanism) knew the fault would be east of us (dipping SW), or west of us (dipping NE).

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