Enhancing Diversity in the Geosciences by Testing the Rigidity of the Eurasia Plate Using GPS

University Of Arizona, Tucson AZ

Investigators

Abstract

Preliminary analyses of GPS-derived crustal motions from 251 continuous GPS stations in west and central Europe cast doubt on the rigidity of western Eurasia. Possible belts of concentrated deformation appear to coincide with prominent seismically active and/or geologically distinct features, such as the Trans-European Suture Zone, the Rhine Graben, and the Pyrenees Mountain belt. But the motions are small and many additional tests of the internal kinematics of the region are required. This project exploits existing data from hundreds of continuously operating GPS stations located in west and central Europe to determine whether or not intraplate seismicity is accompanied by observable intraplate deformation. The project involves: (1) acquisition and analysis of new data from existing continuous GPS networks in Europe and the Mediterranean region; and (2) statistical tests of western Eurasia plate rigidity in order to explore possible explanations for observed crustal motions such as microplate motion, interplate and inter-microplate elastic strain accumulation, diffuse intraplate deformation, ephemeral strain accumulation associated with glacial isostatic adjustment, site specific secular motion, and time correlated measurement error. The science objectives will provide an opportunity to attract new Geoscience majors with physical disabilities, an important underrepresented group in the Geosciences. Specifically and in conjunction with the University of Arizona Disability Resource Center, the project will (1) increase awareness of Geoscience research opportunities; (2) develop strong mentoring relationships between undergraduate students with physical disabilities and more senior researchers; and (3) create meaningful undergraduate research experiences, including hypothesis testing and dissemination of results at a student-run symposium and at national level scientific conferences. The main objective of this project is to test the internal rigidity of the western Eurasia plate. The theory of plate tectonics is based upon the idea that relative motion between adjacent plates is accommodated mostly within narrow zones of intense deformation. However, abundant intraplate seismicity and strain accumulation observed by space geodesy indicates that this hypothesis is not strictly valid. Where plate boundaries involve continental lithosphere the zones of interplate deformation may extend hundreds of kilometers into the continental interiors, blurring the distinction between interplate and intraplate deformation. This project exploits existing of data from hundreds of continuously operating GPS stations located in west and central Europe to determine whether or not intraplate seismicity is accompanied by observable intraplate deformation. Understanding the rigidity of continental plate interiors is also important for earthquake hazards assessment because intraplate earthquakes may have very long recurrence periods, and are thus difficult to anticipate. The project will broaden participation and diversity among Geoscience majors by creating meaningful and broadly accessible undergraduate research experiences, including hypothesis testing, and dissemination of results at a student run symposium and at national scientific conferences.