A summary plot of the events located by the USGS as of Thursday 07 April, morning (US Eastern Time). Credit: Image by C. J. Ammon, Penn State, data from the US Geological Survey.
A summary plot of the events located by the USGS as of Sunday morning (US Eastern Time). Estimates of historic rupture areas are also shown; Credit: Image by C. J. Ammon, Penn State, rupture outlines from Hiroo Kanamori, Caltech, data from the US Geological Survey.
A comparison of an estimate of coseismic slip (created in collaboration with Thorne Lay at UC Santa Cruz and Hiroo Kanamori at CalTech) with the aftershocks and bathymetry. You can read about the model at the link to preprint of the Earth, Planets, Space manuscript. Some details: The slip was estimated using distantly recorded P waveforms and Relative Source Time Functions estimated from Rayleigh wave signals using the Mw 7.5 foreshock as an empirical Green function and from high-sample rate (continuous) GPS observations. Click here to see the model. Click here to see inversion summary.
Credit: Rupture model by C. J. Ammon and Mike Cleveland Penn State, T. Lay, UC Santa Cruz, and H. Kanamori, Caltech. Aftershock data from the US Geological Survey.
Updated on 8 April, 2011. The symbol sizes may not match the aftershock animation. The depth is encoded in the colors: red < 33; orange < 101; yellow < 201; green < 301; blue deeper than 301. I will update when I get some time. Credit: Animation by C. J. Ammon, Penn State, data from the US Geological Survey. If you want a copy and do not have QuickTime Pro to download the source, try using "Download Linked File" on this link (43 mBytes).
Very nice GPS data from Japan. The data show large eastward offsets produced by the mainshock (which occurred at time zero) and a large, early aftershock (Mw 7.9) that occurred just under 30 minutes later. Credit: Preliminary GPS time series provided by the ARIA team at JPL and Caltech. All original GEONET RINEX data provided to Caltech by the Geospatial Information Authority (GSI) of Japan. Chart by C. J. Ammon, Penn State.
Location of GPS station 0216 and the recent aftershocks. The Mw 9.0 mainshock caused sliding along much of the area covered by aftershocks. The large aftershock 30 minutes later is located close to the GPS observing station.
|Charles J. Ammon, Professor of Geosciences
Department of Geosciences
440 Deike Bldg.
University Park, PA 16802