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1. Understanding Alaska’s Earthquakes

   Abers, GA; Adams, AN; Haeussler, PJ; Roland, E; Shore, PJ; Wiens, DA; Schwartz, SY; Sheehan, AF; Shillington, DJ; Webb, S; et al (October 2019, Eos)

   NORTH AMERICA’S LARGEST EARTHQUAKES and most powerful volcanic eruptions occur along the Alaska Peninsula subduction zone, a meeting of two tectonic plates that sweeps an arc across the North Pacific margin between Alaska and Russia. However, studies that would help us understand these hazards are few and far between in this remote, sparsely populated region. A major new shoreline- crossing community seismic experiment spans the Alaska Peninsula subduction zone, with the intention of filling gaps in our knowledge of this region. Information that we collect along this margin can provide direct information about many first- order questions about subduction zone processes that influence earthquakes and volcanism. 

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2. Physics of Megathrust Earthquakes: Introduction

   https://doi.org/10.1007/s00024-019-02308-y  

   Barbot, Sylvain (September 2019, Pure and Applied Geophysics)
3. How Earthquakes Start and Stop

   https://doi.org/10.1029/2018EO094513  

   Marsan, David; Beroza, Greg; Gomberg, Joan (March 2018, Eos)

   Earthquakes: Nucleation, Triggering, Rupture, and Relationships to Aseismic Processes; Cargèse, Corsica, France, 2–6 October 2017 

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4. The generation of large earthquakes

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   Kato, Aitaro; Ben-Zion, Yehuda (January 2021, Nature Reviews Earth & Environment)

   null (Ed.)
5. Frequency-difference backprojection of earthquakes

   https://doi.org/10.1093/gji/ggac323  

   Neo, Jing Ci; Fan, Wenyuan; Huang, Yihe; Dowling, David (August 2022, Geophysical Journal International)

   SUMMARY Backprojection has proven useful in imaging large earthquake rupture processes. The method is generally robust and requires relatively simple assumptions about the fault geometry or the Earth velocity model. It can be applied in both the time and frequency domain. Backprojection images are often obtained from records filtered in a narrow frequency band, limiting its ability to uncover the whole rupture process. Here, we develop and apply a novel frequency-difference backprojection (FDBP) technique to image large earthquakes, which imitates frequencies below the bandwidth of the signal. The new approach originates from frequency-difference beamforming, which was initially designed to locate acoustic sources. Our method stacks the phase-difference of frequency pairs, given by the autoproduct, and is less affected by scattering and -time errors from 3-D Earth structures. It can potentially locate sources more accurately, albeit with lower resolution. In this study, we first develop the FDBP algorithm and then validate it by performing synthetic tests. We further compare two stacking techniques of the FDBP method, Band Width Averaged Autoproduct and its counterpart (BWAP and non-BWAP), and their effects in the backprojection images. We then apply both the FDBP and conventional backprojection methods to the 2015 M7.8 Gorkha earthquake as a case study. The backprojection results from the two methods agree well with each other, and we find that the peak radiation loci of the FDBP non-BWAP snapshots have standard error of less than 0.33° during the rupture process. The FDBP method shows promise in resolving complex earthquake rupture processes in tectonically complex regions. 

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