Project Details
Projekt
Bridging Geodesy and Seismology for improved and automated estimation of faulting events
Applicant
Professorin Dr. Henriette Sudhaus
Subject Area
Geophysics
Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
Geodesy, Photogrammetry, Remote Sensing, Geoinformatics, Cartography
Term
from 2015 to 2022
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 276464525
Earthquake generally occur on tectonically loaded faults. Fast fault slip generates seismic waves and therefore earthquakes that globally pose a hazard to our growing societies. Also associated slower slip contributes silently to the relaxation of loaded faults. Considered we would know the fault loading and could measure fast and slow slip precisely, we would be able to derive the fault's slip deficit. With amount and spatial distribution of the slip deficit, we could estimate locations and magnitudes of potential future earthquakes, which is figuratively the holy grail of seismology.Today we are about to grasp these players of the seismic cycle at a few high-strain plate boundaries, e. g. in Japan, achieved by employing dense and expensive multi-parametric sensor networks. In particular the combination of seismic and geodetic sensors proved to be a key to capture both dynamic and static ground motion of seismic and aseismic slip. However, in our chase for the grail we have built on ever more focused observations and tailored analyses, neglecting to promote globally applicable and consistent modelling frameworks with data integration, with error estimation being our step child and trade-offs and non-unique results regular guests. It mostly remains unquantified how reliable the retrieved rupture images are. Also, how these findings compare to intraplate tectonic environments with less fault activity is unclear. To gain more general knowledge on fast and slow fault slip I propose to widen the scope. Global observations of fault slip also inside continents are possible independently of local networks by using the teleseismic networks and spaceborne Interferometric Synthetic Aperture RADAR (InSAR). Two new high-performance civil radar satellite missions are in space since 2014. They will provide SAR data with high reliability and I therefore distinguish InSAR as a very potent technique that, combined with teleseismic waveforms, will timely enhance global seismology. What is needed and part of this project is a common modelling framework for teleseismic and InSAR data and further an inclusive modelling of fast and slow slip. Here I plan to develop the kinematic rupture modelling towards more precise, but robust, slip images that are verified by uncertainty estimates based on rigorous error propagation. The goal is to enrich earthquake catalogues with better information on fault locations, fault extension and slip to support hazard assessments. Further, I want to quantify the resolution limits to extract reliable values on the natural variability of rupture properties, poorly known so far, and scaling laws for fast and slow ruptures. The developments shall become standardized routines and will enable automated data analysis and increased performance for the growing data inflow. Better methods and more robust results gained in comprehensive studies of fault slip will bring global seismology forward to new realms beyond magnitude.
DFG Programme
Independent Junior Research Groups
International Connection
Saudi Arabia, United Kingdom
