Does climate change affect the earthquake cycles of intracontinental faults? An investigation based on 3D finite-element modelling

• Applicant: Professorin Dr. Andrea Hampel
• Subject Area: Geology
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 576829153

Modern climate change is associated with an increase in average temperatures and variations in precipitation, which will lead to considerable mass changes of ice and water bodies on Earth's surface in the future decades to millennials. As indicated by the palaeoseismological record of Late Pleistocene and Holocene fault activity and previous numerical modelling studies, changes in ice and water volumes have the potential to affect crustal deformation and earthquake activity in both tectonically stable and tectonically active regions. Notably, the ice and water volumes losses that have occurred over the past decades were already sufficiently large to cause discernible crustal deformation and alterations of seismicity patterns, for example, in Alaska and Greenland. As climatically enforced mass changes are expected to continue in the future, a better understanding of their impact on crustal deformation is crucial for future seismic hazard evaluations. The goal of the proposed project will be to provide quantitative information on the impact of climatically enhanced shrinkage of ice-sheets, glaciers and lakes on the seismicity of intracontinental normal, reverse and strike-slip faults in low-strain to tectonically active regimes. To achieve this goal, we will use 3D finite-element models, which simulate earthquake cycle sequences with alternating interseismic and coseismic phases on the model faults. As a major advancement compared to previous modelling studies, our approach will allow quantifying the effect of climate-induced unloading on the faulting in terms of coseismic slip, earthquake magnitudes as well as the frequency and recurrence intervals of earthquakes. Furthermore, the proposed project will investigate, for the first time, how earthquake-triggered co- and postseismic stress changes interfere with the stress changes caused by unloading and rebound. In a systematic parameter study, the influence of various parameters including the magnitude of the load, its temporal evolution and distribution relative to the fault, the relation between the length of the interseismic phase and the duration of unloading and the viscosity structure of the lithosphere on the results will be evaluated. The project results will provide quantitative constraints about climate-triggered changes in seismicity and contribute to improved seismic hazard evaluations for regions that experience loss in ice and water volumes due to modern climate change.

• DFG Programme: Research Grants