‘At present there is no possibility of earthquake prediction in the popular sense; that is no one can justifiably say that an earthquake of consequence will affect a named location on a specific future date. It is uncertain whether any such prediction will be possible in the foreseeable future; the conditions of the problem are highly complex. One may compare it to the situation of a man who is bending a board across his knee and attempts to determine in advance just where and when the crack will appear.’ Richter (1958, pp ). Ge Learning from Crackling Noise - What can small earthquakes tell us about future large ones?

Ge Learning from Crackling Noise - Agenda, readings and presentations will be posted atftp://ftp.gps.caltech.edu/pub/avouac/Ge /ftp://ftp.gps.caltech.edu/pub/avouac/Ge / 2 articles presented each week Please attend all seminars What can small earthquakes tell us about future large ones?

outline My motivation for the subject Introduction to Crackling noise and some of the articles in the reading list

(Stevens and Avouac, GRL, 2015) Interseismic Coupling-Slip rate on MHT S

The moment deficit accumulates in the interseismic period at a rate of 18 x10 19 Nm/yr. Geodetic rate Geological rate (Stevens and Avouac, GRL, 2015)

Gutenberg-Richter distribution releasing all the slip deficit

(Stevens and Avouac, GRL, in press)

More, larger EQs to come? How big when? The Mw 7.8 Gorkha Earthquake

Seasonal variations of surface load derived from GRACE (Bettinelli et al, 2007, Chanard et al., JGR, 2014) GPS time series Sensitivity of Himalayan seismicity to the Monsoon cycle

Foreshocks

Ge Learning from Crackling Noise - What can small earthquakes tell us about future large ones? Can we extrapolate to large event the statistics of small one? (may be not because size effect: e.g., Pacheco et al, 1992; Dahmen et al, 1998) Do small and large EQs belong to the same physical system? (e.g., Wesnousky, 1994)

Basic EQ statistics phenomelogy Gutenberg-Richter law Omori Law Reverse Omori Law Bath’s Law Waiting time scaling law Productivity Law …

‘The Earthquake History in a Fault Zone Tells Us Almost Nothing about Mmax’ (Zöller and Holschneider, SRL, 2016)

‘Induced Seismicity: What is the Size of the Largest Expected Earthquake?’ maximum expected magnitude MT in a time window of length T for a injection of volume V Satisfying? (Zöller and Holschneider, BSSA, 2013) (McGarr, JGR, 2014)

Basic EQ statistics phenomelogy Gutenberg-Richter law Omori Law Reverse Omori Law Bath’s Law Waiting time scaling law Productivity Law … These laws also apply ‘Crackling Noise‘

‘Analogies Between the Cracking Noise of Ethanol- Dampened Charcoal and Earthquakes’ et al., PRL, 2015)

‘Analogies Between the Cracking Noise of Ethanol- Dampened Charcoal and Earthquakes’ et al., PRL, 2015)

Andrade and Critical Time-to-Failure Laws in Fiber- Matrix Composites: Experiments and Model (Nechad et al, Cond. Mat., 2005)

Creep Ruptures in Heterogeneous Materials (Nechad et al, PRL, 2005)

Creep Ruptures in Heterogeneous Materials (Nechad et al, PRL, 2005)

‘Heterogeneity: The key to failure forecasting’ (Vasseur, Scientific Reports, 2015)

‘Heterogeneity: The key to failure forecasting’ (Vasseur, Scientific Reports, 2015)

‘Heterogeneity: The key to failure forecasting’ (Vasseur, Scientific Reports, 2015)

Acceleration of seismicity rate release before large earthquake is reported (e.g., Bowman and King, 1998; Bouchon et al, 2015; Schurr et al

‘The long precursory phase of most large interplate earthquakes’ (Bouchon et al, NGEO, 2015)

seismicity changes before large earthquakes (Bowman and King, 1998; King and Bowman, 2001)

Foreshocks: Nucleation process or just what is expected from EQs triggering and the GR law? (Helmstetter et al, 2003)

A most studied example of crackling noise: Barkhausen effect (Sethna, ‘Crackling noise’, Nature, 2001) The typical size of the largest avlanche scales with

Barkhausen effect (‘noise’ due to jerky magnetisation of a ferro-magnetic material) sroY

Conclusion Crackling noise can inform about the structural integrity of materials. The characteristics of extreme events might or might not be predicted depending on the noise statistical characeristics. Failure time of some heterogeneous materials can be predicted from strain history and crackling noise. Can the tools and concepts developed in this field be if any use in earthquake physics?

By next week look at the reading material and let me know a subjetc/paper of interest to you. Be brave, pick a topic outside your confort zone.