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PhD Candidate Nooshin Saloor wins Outstanding Student Paper Award for her AGU 2017 Poster

January 25, 2018

Awardee Nooshin Saloor with posterPhD Candidate Nooshin Saloor was awarded an Outstanding Student Paper Award (OSPA) for her AGU 2017 Fall Meeting Poster, "An Attempt to Rationalize the Depth-Distance Correction Q(Δ,h) of the mb Formula." OSPA awards are typically given to the top 2-5% of presenters in a section. Nooshin Saloor works with PhD advisor Emile Okal to explore Earthquake source parameters and seismic scaling laws for Intermediate and deep Earthquakes.  Below is her abstract:
"The body-wave magnitude mb remains an important quantifier of earthquakes, especially those of moderate size. We recall that it is computed according to the Prague formula, where Q is an empirical function obtained from a contoured plot by Richter [1958]. The history of its original derivation (especially its dependence on h) by Gutenberg and Richte [1945] remains murky and largely unsubstantiated, at a time when neither the concept of double-couple, nor the precise structure of the Earth (low-velocity zone; anelastic attenuation) were known.

Based on the assumption that events of common moment M0 should have the same mb for all depths (and obviously at all distances), we examine both theoretically and with the help of large populations of synthetic seismograms the contributions to  Q(D ,h)  of such parameters as geometrical spreading, surface response coefficients, the average layering of the mantle (including the low-velocity zone), the variation of attenuation with depth and the unavoidable use of instruments of various designs, in an attempt to rationalize some of the intriguing details of the Q(D ,h) contours."