Thursday, March 14, 2019 - AGS Luncheon Lecture
Ground Failures Induced by Seismic Shaking During the 2018 Anchorage
Noon Luncheon 11:30-1:00 pm
Strong ground motions during the November 30, 2018 M7 Anchorage, Alaska earthquake triggered numerous ground failures in artificial fill and natural materials over a >5000 km2 area in south-central Alaska. Shaking generated by the intraslab earthquake (40 km deep) produced peak ground accelerations of 0.3-0.8 g throughout much of the greater Anchorage-Matanuska-Susitna Valley urban area. Post-earthquake aerial and ground surveys, spanning December 1–10, focused on ground failures (liquefaction, lateral spreads, and landslides) in artificial fill and natural materials. Coseismic failures in artificial fill damaged engineered road and rail embankments and buildings, particularly residential homes. Ground failures in natural materials occurred where landslides were
Rob Witter, US Geological Survey, Alaska Science Center, Anchorage
Dr. Rob Witter is a research geologist at the USGS Alaska Science Center in Anchorage. He received his undergraduate degree from Whitman College, Walla Walla, Washington and his PhD from the University of Oregon in Eugene. Dr. Witter’s research emphasizes paleoseismology of active faults with a particular focus on neotectonics of convergent margins. His research interests also include: examining the range of rupture variability during subduction zone earthquakes; using paleogeodesy to estimate the amount of vertical displacement caused by past earthquakes; investigating tsunami deposits to better characterize tsunami hazards; and improving public education in geologic hazards. Prior to joining the USGS, Dr. Witter designed and implemented the tsunami hazard mitigation program for the Oregon Department of Geology and Mineral Industries. He also worked as an earth science consultant in Walnut Creek California.