Researchers from Southern Illinois University (SIU) and Saint Louis University (SLU) are deploying 45 broadband seismographs and three short-period seismic arrays in the Wabash Valley in Illinois and Indiana. The experiment is part of the on-going EarthScope project and is aimed at better understanding the driving forces of the Wabash Valley Seismic Zone (WVSZ) such as regional lithospheric stresses exploiting a weak zone, glacial isostatic adjustment, and lithospheric basal tractions induced by mantle dynamics. By applying a variety of seismic techniques including body wave and surface wave tomography, receiver functions, shear-wave splitting, and mapping of background crustal seismicity, this seismic experiment will illuminate the seismic structure beneath the study area and impose valuable constraints on driving mechanism for this geologically enigmatic feature as well as further our understanding of intraplate earthquakes.
This project directly advances the Earthscope mission to advance our understanding of intraplate seismic zone dynamics and to improve seismic hazard assessments in the midcontinent. It allows for more quantitative comparisons between the WVSZ and the New Madrid Seismic Zone to its south. It furthers the education of a PhD student at SIU and one at SLU as well as sponsors undergraduate research at both institutions. The students are involved in a number of different aspects of the research from the fieldwork comprising station installation, servicing, and data collection to data analysis and interpretation. These students learn a number of seismic analytical methods that point them towards further research and study within the framework of EarthScope and other cutting-edge scientific initiatives. The PIs of the project work with science teachers at several high schools located in the study area. Two seismographs are located on school property, with display for students to view real-time seismic data and provide access to educational resources from Earthscope.
