# Natural Time and Nowcasting Earthquakes: Are Large Global Earthquakes Temporally Clustered?

@article{Luginbuhl2018NaturalTA, title={Natural Time and Nowcasting Earthquakes: Are Large Global Earthquakes Temporally Clustered?}, author={Molly Luginbuhl and John B. Rundle and Donald L. Turcotte}, journal={Pure and Applied Geophysics}, year={2018}, volume={175}, pages={661-670} }

The objective of this paper is to analyze the temporal clustering of large global earthquakes with respect to natural time, or interevent count, as opposed to regular clock time. To do this, we use two techniques: (1) nowcasting, a new method of statistically classifying seismicity and seismic risk, and (2) time series analysis of interevent counts. We chose the sequences of $$M_{\lambda } \ge 7.0$$Mλ≥7.0 and $$M_{\lambda } \ge 8.0$$Mλ≥8.0 earthquakes from the global centroid moment tensor (CMT… Expand

#### 16 Citations

Statistical physics models for aftershocks and induced seismicity

- Geology, Medicine
- Philosophical Transactions of the Royal Society A
- 2018

Nowcasting is introduced to extend RI forecasting to time-dependent seismicity, for example, during an aftershock sequence, and it is shown how nowcasting can be used to assess the success of these efforts to reduce the seismic activity. Expand

Nowcasting Earthquakes in the Bay of Bengal Region

- Geology
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Statistical quantification of observed seismicity is important for understanding earthquake dynamics and future risk in any seismic-prone region. In this paper, we implement the idea of nowcasting… Expand

Contemporary Earthquake Hazards in the West-Northwest Himalaya: A Statistical Perspective through Natural Times

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Himalayan earthquakes have deep societal and economic impact. In this article, we implement a surrogate method of nowcasting (Rundle et al., 2016) to determine the current state of seismic hazard… Expand

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- Reports on progress in physics. Physical Society
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The focus is on anticipating the earthquake rupture before it occurs, rather than characterizing it rapidly just after it occurring, and new types of data, models, and computational power may provide avenues for progress using machine learning that were not previously available. Expand

Detrended fluctuation analysis of seismicity and order parameter fluctuations before the M7.1 Ridgecrest earthquake

- Geology
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- 2020

Detrended fluctuation analysis (DFA) has been recently applied for the investigation of temporal correlations between the earthquake magnitudes before major earthquakes. Here, we employ DFA together… Expand

Natural Time Analysis: The Area under the Receiver Operating Characteristic Curve of the Order Parameter Fluctuations Minima Preceding Major Earthquakes

- Medicine, Computer Science
- Entropy
- 2020

Fifteen distinct minima—observed simultaneously at two different natural time scales and deeper than a certain threshold—are found on analyzing the seismicity of Japan from 1 January 1984 to 11 March 2011 (the time of the M9 Tohoku EQ occurrence) 1 to 3 months before large EQs. Expand

Investigation of the temporal correlations between earthquake magnitudes before the Mexico M8.2 earthquake on 7 September 2017

- Geology
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Abstract By employing Detrended Fluctuation Analysis (DFA), which has been established as a standard method to investigate long range correlations in nonstationary time series, we study the temporal… Expand

Minima of the fluctuations of the order parameter of seismicity and earthquake networks based on similar activity patterns

- Geology
- 2019

Abstract Natural time analysis has provided an order parameter for seismicity. It has been shown that the fluctuations of this order parameter exhibit characteristic minima before strong earthquakes… Expand

Natural Time Analysis of Seismicity within the Mexican Flat Slab before the M7.1 Earthquake on 19 September 2017

- Medicine, Computer Science
- Entropy
- 2020

It is shown that, after the minimum of ΔS, the order parameter of seismicity starts diminishing, thus approaching gradually the critical value 0.070 around the end of August and the beginning of September 2017, which signals that a strong earthquake is anticipated shortly in the flat slab. Expand

Precursory variations of Tsallis non-extensive statistical mechanics entropic index associated with the M9 Tohoku earthquake in 2011

- Physics
- 2020

Applying natural time analysis, which has been introduced by the authors in 2001, to the Japanese seismic data, we find that the system enters the critical stage upon the occurrence of M = 4.2–5.0… Expand

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