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<div style="margin: 0px;"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(200, 38, 19);"><b>Two sides of a coin: Massive liquefaction-induced flowslides and limited lateral spreading</b> </span><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> </span></div>
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<div style="margin: 0px;"><font color="#000000"><span style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">Ben Mason, </span></font><span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Associate
Professor, Oregon State University</span></div>
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<div style="margin: 0px;"><span style="margin: 0px; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">During the first part of the talk, I will focus on three massive flowslides that occurred along the east side of the
Palu Valley following the 2018 earthquake near Palu, Indonesia. The post-earthquake reconnaissance was supported by the Geotechnical Extreme Events Reconnaissance (GEER) Association. I will describe the field reconnaissance, including pre-field planning, </span><span style="margin: 0px; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">remote
imaging, and post-field data collection as well as some simple finite difference modeling aimed at understanding the importance of soil liquefaction on the flowslide displacements. During the second part of the talk, I will focus on a mechanics-based model developed
to estimate limited lateral spreading displacements. Finally, I will compare and contrast the two extremes (i.e., flowsliding versus limited lateral displacements) and give some potential thoughts of future directions. The talk is largely based on two articles,
and I’ve posted the bibliographical information below.</span></div>
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<b style="color: rgb(200, 38, 19); font-family: Arial, Helvetica, sans-serif; font-size: 11pt; background-color: white;"><span style="margin:0px;font-weight:400;font-size:15px;font-family:"Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif;color:black;background-color:rgb(255, 255, 255)">
<div style="margin:0px"><font color="black" face="Times"><span style="margin:0px;font-size:14px">———</span></font></div>
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</span><font face="Times" style="font-size:15px;font-weight:400;background-color:rgb(255, 255, 255);color:black">Mason, H. B., Montgomery, J., Gallant, A. P., Hutabarat, D., Reed, A. N., Wartman, J., Irsyam, M., Simatupang, P. T., Alatas, I. M., Prakoso, W.
A., Djarwadi, D., Hanifa, R., Rahardgo, P., Faizal, L., Harnanto, D. S., Kawanda, A., Himawan, A., and Yasin, W. (2021). East Palu Valley flowslides induced by the 2018 MW7.5 Palu-Donggala earthquake, <i>Geomorphology</i> 373, 107482-1-17. 10.1016/j.geomorph.2020.107482<br>
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</font><span style="margin:0px;font-weight:400;font-size:15px;font-family:"Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif;color:black;background-color:rgb(255, 255, 255)"><font face="Times">Leshchinsky,
B. A., Mason, H. B., Olsen, M. J., and Gillins, D. T. (2018). Lateral spreading within a limit equilibrium framework: Newmark sliding blocks with degrading yield accelerations, <i>Geotechnique</i> 68(8), 699-712. 10.1680/jgeot.16.P.292</font></span></b></div>
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