Title |
Gravitational body forces focus North American intraplate earthquakes
|
---|---|
Published in |
Nature Communications, February 2017
|
DOI | 10.1038/ncomms14314 |
Pubmed ID | |
Authors |
Will Levandowski, Mark Zellman, Rich Briggs |
Abstract |
Earthquakes far from tectonic plate boundaries generally exploit ancient faults, but not all intraplate faults are equally active. The North American Great Plains exemplify such intraplate earthquake localization, with both natural and induced seismicity generally clustered in discrete zones. Here we use seismic velocity, gravity and topography to generate a 3D lithospheric density model of the region; subsequent finite-element modelling shows that seismicity focuses in regions of high-gravity-derived deviatoric stress. Furthermore, predicted principal stress directions generally align with those observed independently in earthquake moment tensors and borehole breakouts. Body forces therefore appear to control the state of stress and thus the location and style of intraplate earthquakes in the central United States with no influence from mantle convection or crustal weakness necessary. These results show that mapping where gravitational body forces encourage seismicity is crucial to understanding and appraising intraplate seismic hazard. |
X Demographics
Geographical breakdown
Country | Count | As % |
---|---|---|
United States | 18 | 30% |
United Kingdom | 6 | 10% |
China | 1 | 2% |
Peru | 1 | 2% |
Panama | 1 | 2% |
Switzerland | 1 | 2% |
Chile | 1 | 2% |
Greece | 1 | 2% |
Canada | 1 | 2% |
Other | 3 | 5% |
Unknown | 26 | 43% |
Demographic breakdown
Type | Count | As % |
---|---|---|
Members of the public | 46 | 77% |
Scientists | 10 | 17% |
Science communicators (journalists, bloggers, editors) | 3 | 5% |
Practitioners (doctors, other healthcare professionals) | 1 | 2% |
Mendeley readers
Geographical breakdown
Country | Count | As % |
---|---|---|
Portugal | 1 | 2% |
Italy | 1 | 2% |
Unknown | 55 | 96% |
Demographic breakdown
Readers by professional status | Count | As % |
---|---|---|
Researcher | 14 | 25% |
Student > Ph. D. Student | 13 | 23% |
Professor | 4 | 7% |
Student > Bachelor | 3 | 5% |
Student > Doctoral Student | 2 | 4% |
Other | 7 | 12% |
Unknown | 14 | 25% |
Readers by discipline | Count | As % |
---|---|---|
Earth and Planetary Sciences | 35 | 61% |
Computer Science | 2 | 4% |
Agricultural and Biological Sciences | 1 | 2% |
Medicine and Dentistry | 1 | 2% |
Engineering | 1 | 2% |
Other | 0 | 0% |
Unknown | 17 | 30% |