Date: January 18, 2018
Speaker: Jeffrey R. Keaton, Amec Foster Wheeler (Wood)
Topic: Suggested Enhancements to the Geologic Model Complexity Rating System
The suggested Geologic Model Complexity Rating System, introduced in 2014, was developed considering the 1993 Oregon rockfall hazard rating sys-tem with four rating levels. Five of the nine Geologic Model Complexity Rating System components pertained to geologic complexity; four regional components (genetic, structural/deformation, alteration/dissolution, and weathering/erosion) and one site-scale component. The other Geologic Model Complexity Rating System components were: terrain features, information quality, geologist competency, and level of effort. A pairwise comparison of components for a landslide hazard study, using a multi-factor decision analysis procedure called Analytic Hierarchy Process (AHP), weighted geologist competency highest (20%), fol-lowed by genetic complexity and deformation (each 18%) and site-scale co-plexity and level of effort (each ~11%). The other four components had weights from 8% to 3%. The 1-9 scoring for AHP, with 1 indicating that components are equal and 9 indicating one is extremely more important, appeared to be useful for objective comparisons. The AHP matrix configuration lists components in the same order in rows and columns. Regional complexity is now being considered as a single four-element component that depends not only on the basic geology of the site area, but also on the purpose of the geologic evaluation. Thus, the suggested enhancements streamline the Geologic Model Complexity Rating System, reducing it from nine components to six, but also complicates it by considering basic geology and purpose of evaluation as fundamentally important to the geologic model. These enhancements bring the suggested Geologic Model Complexity Rating System into alignment with the Oregon rockfall hazard rating system, which included facility components (i.e., what is at risk) for which the hazard was being rated.
Speaker: Jahn’s Distinguised Lecturer – Scott Anderson
Speaker: Aaron Schlessinger
Topic: Pavement Enhancement with High Performance Geogrids
Speaker: Kelin X. Whipple, Professor, ASU SESE
Speaker: John Rockhill
John D. Rockhill is an archaeologist with Amec Foster Wheeler in Phoenix, Arizona with 20 years of field and laboratory experience in the southwestern United States, Egypt and Sudan. John was born and raised in Safford, Arizona and received his Bachelor of Science degree in Biology in 1975 from the U.S. Air Force Institute through the University of South Carolina. John has worked on and directed a number of field projects with emphasis on large scale survey, mapping and excavation of prehistoric and historic sites and their features and the laboratory analysis of lithic, glass and metal artifacts.
Please join the Phoenix Chapter of the Association of Environmental and Engineering Geologists (AEG), the American Institute of Professional Geologists (AIPG), and the Arizona Hydrological Society (AHS) at the 11th Annual Arizona AEG student night on March 30, 2017. This year at Student Networking Night we will pair students and professionals for mock-interviews for the students and lightning talks by professionals. This is an opportunity for students to learn how diverse the geologic field is and what varying aspects are available as a professional. This is also a night for professionals to meet students and learn what they are studying and what they hope to do once they graduate.
The event will begin at 6:00 pm and will be held in the La Paz Room of the Student Memorial Union on the Tempe campus of Arizona State University. For directions, please refer to the accompanying map of the ASU Campus and Student Memorial Union, or visit http://www.asu.edu/map/interactive/.
Speaker: Mostafa Khoshmanesh, ASU SESE PhD Student
Topic: Insights into fault behavior and underlying processes from geodesy, seismology, and geology
Geodetic techniques, measuring the ground surface movements at sub-millimeter precision, provide the seismotectonics community with an imperative opportunity to study faulting behavior at unprecedented details. Provided by these observations, we are now aware that part of the tectonic stress is released through aseismic slip or creep. The spatial extent and rate of creep determines the fault earthquake potential. Also, the temporal variation of creep rate, so-called Slow Slip Events (SSE) are capable of triggering major earthquakes. Kinematic models developed to integrate seismic and geodetic observations, allow resolving the spatiotemporal distribution of creep on the fault surface, disregarding the underlying mechanism. Focusing on the Central San Andreas Fault (CSAF) as my primary study area, in this presentation I will explain the methods that I developed to study spatial and temporal evolution of fault creep. My results show that creep rate on CSAF is not steady and episodic SSEs are observed on the entire seismogenic depth in a semi-periodic manner. I will briefly discuss the possible underlying mechanisms to explain the observed SSEs. I conclude that transient elevation of water pressure trapped in intergranular pore spaces, due to compaction of material within the fault zone is a feasible mechanism for initiating SSEs on the CSAF. I will also provide evidence for the link between SSEs on the CSAF and earthquakes on neighboring locked zones, including the 2004 Mw6.0 Parkfield earthquake. Studies of this kind can greatly improve the probabilistic earthquake forecasts models by considering the periodicity of these SSEs over the conventional assumption of constant loading rate.
Mostafa Khoshmanesh is a PhD candidate in the School of Earth and Space Exploration at Arizona State University. He received his BA in surveying engineering in 2010 and MS in Geodesy in 2013, both from Iran. Since the beginning of his PhD in geological science in 2014, he has been a research assistant in Remote Sensing and Tectonic Geodesy Laboratory at ASU. His main area of interest is tectonic geodesy, with concentration on studying seismic and aseismic faulting processes. For this purpose he uses advanced Interferometric Synthetic Aperture Radar (InSAR) methods, combined with other geodetic, seismic, and geologic data set. His recent research on the time-dependent model of creep along the Central San Andreas Fault in California, has been published in high ranked Journal of Geophysical Research and is one of the most accessed articles in 2015.