FAULTMOD · Quantitative understanding of the interseismic evolution of fault properties: numerical modelling using lab-experiments
6РП — Действия „Мария Кюри“
- Период
- 2006-01-01 → 2007-12-31
- Финансиране от ЕС
- 80 000 €
- Участници
- 1
- Схема
- IRG
Линиите свързват координатора с партньорите.
Накратко на български
Свойствата на разломите в земната кора се анализират чрез лабораторни опити и компютърни модели за бавната деформация на скалите. Това помага за по-доброто разбиране на поведението на сеизмогенните зони и свързания с тях риск от земетресения.
Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.
Резултати накратко
Final Activity Report Summary - FAULTMOD (Quantitative understanding of the interseismic evolution of fault properties: numerical modelling using lab-experiments)
A better understanding of the rheological properties of fault zones is key to understanding the behaviour of seismogenic zones and the seismic hazard associated with them. Advances in the performance of computers and numerical methods have allowed considerable progress in the modelling of the dynamic rupture propagation in the past 10 years. One limitation of this approach stems from the paucity of the available information regarding the fault properties at the onset of the rupture and the capacity of the interseismic processes to maintain or re-create complexity. This work has therefore focused on finding new ways to constrain the rheology of fault zones, in particular during the interseismic periods. Particular attention was paid to the evaluation and actual use of the measurement errors during laboratory experiments. An innovative probabilistic (Bayesian) modelling framework was designed for this purpose and enabled the propagation of these sources of variability through forward models of seismogenesis. The challenge consisted in 1) designing new techniques for the quantitative analysis of experimental slow rock deformation, and 2) proposing the first physics-based earthquake renewal model (probability density function for the time to failure). The methodology developed in this project proved useful to bridge the gap between experimental data and numerical models of seismogenesis and it could be applied to the integration of other types of observations. Indeed, we also initiated a very promising study on the analysis of dense surface deformation fields obtained from high-resolution optical images as a constraint for source models and models of fault-zone rheology. More importantly, our Bayesian methodology also enabled us to produce simulated times to failure of the same (probabilistic) nature as the basic ingredients of seismic hazard assessment.
Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз
Цел на проекта
Constraints on the recurrence times and the potential sizes of earthquakes on a fault are crucial prerequisites for seismic hazard assessment. The recovery of fault strength as well as changes in effective stress after a large earthquake depend on the tim e-evolution of the hydraulic, frictional, creep and poroelastic properties of the healing fault zone. The underlying physical and chemical processes determine how long it will take for different parts of the fault to reach failure again, thus controlling b oth the timing and size of the next rupture. To investigate this, we will conduct forward modelling of the hydraulic and strength properties of fault zones during the interseismic period using a Bayesian methodology. By implementing constitutive relationsh ips based on laboratory data, and knowing the associated uncertainties, we will achieve a new measure of robustness in process-based deterministic fault models. However, existing experimental data are rarely adequate to completely define the behaviour of a given fault gouge composition under the hot, wet conditions relevant to crustal fault zones. We will therefore work in collaboration with a European center for high temperature rock and fault mechanics, to develop experiments best suited for our modelling .Working at the IPG Strasbourg will enable me to join a geophysics institute committed to the study of earthquakes and actively participating in European projects. In addition, working with Utrecht will give me additional training in rock deformation exper iments. My career opportunities will thus be significantly broadened.The project will provide the EU with the first effort to develop a process-based fault model fully using today's experimental capabilities. Contrary to previous numerical models based on purely empirical relationships, ours will make use of in situ measurements of fault properties. Such an integrative tool will benefit seismic hazard-assessment projects in Europe, in Turkey, and beyond.'
Оригинален текст от CORDIS (на английски).
Участници
- CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE · PARISКоординаторФранция
Връзки
Данни: CORDIS, © Европейски съюз