Scrutinizing and rooting the multiple anomalies of Nepal earthquake sequence in 2015 with the deviation–time–space criterion and homologous lithosphere–coversphere–atmosphere–ionosphere coupling physics

The continuous increasing of Earth observations benefits geosciences and seismicity study but increases greatly the difficulties in understanding and discriminating multiple source data. Although the lithosphere–coversphere–atmosphere-ionosphere (LCAI) coupling paradigm and the deviation–time–space (DTS) criterion were presented for better searching for and understanding the potential seismic anomalies from multiple observations, the strict consistency of spatiotemporal characteristics and homologous physics of multiple-parameter seismic anomalies has not been investigated sufficiently. With the 2015 Nepal earthquake sequence being a typical case, the reported multi-parameter anomalies were systematically reviewed, and their space–time characteristics were summarized thoroughly in this study. Numerical simulation with refined geological structures in three-dimensional space revealed the inhomogeneous crustal stress field alteration (CSFA) along the faults and around the hypocenters of the 2015 Nepal earthquake sequence, which is expected to be the root of the seismic anomalies. The stress-activated positive charge carriers would have given rise to different responses near the ground surface (coversphere), including the microwave dielectric reduction, the additional infrared radiation, and the atmospheric ionization, which subsequently affected the physical properties of the atmosphere and the ionosphere and resulted in abnormal phenomena therein. Based on the DTS criterion and LCAI coupling paradigm, the seismic anomalies of the 2015 Nepal earthquakes were scrutinized strictly, and the retained anomalies were rooted carefully to the regional CSFA as well as its local blocking. Therefore, an integrated LCAI coupling framework with strict space–time correspondence and homologous physics in CSFA was proposed for the 2015 Nepal earthquake sequence. This research provides a definite philosophy as well as a practical solution for scrutinizing the rootable seismic anomalies from multi-parameter observations of earthquakes, which is of scientific meanings for searching earthquake precursors and reaching earthquake prediction.</p

Is there a one-to-one correspondence between ionospheric anomalies and large earthquakes along Longmenshan faults?

On 12 May 2008, a destructive M8.0 earthquake struck Wenchuan County (31.0° N, 103.4° E) in the Longmenshan fault zone of southwestern China. Five years later, on 20 April 2013, another terrible M7.0 earthquake struck Lushan County (30.3° N, 103.0° E) in the same fault area, only 87 km away from the epicenter of the Wenchuan earthquake. In this paper, an integrated wavelet analysis methodology is proposed to detect and diagnose ionospheric total electron content (TEC) anomalies related to seismic activities. Analytic wavelet transform is used to detect ionospheric perturbations, and then cross-wavelet analysis is used to diagnose ionospheric anomalies by gaining further insights into the dynamic relationship between the anomaly variability of ionospheric TEC and geomagnetic indices for the same set of observations. The results show that a significant ionospheric disturbance occurred on 9 May 2008 above the forthcoming epicenter, 3 days prior to the Wenchuan earthquake. However, we did not observe an ionospheric anomaly over the epicenter of the Ya'an earthquake during the 1 month period before the shock. Finally, we discuss the possible interpretations of the different seismo-ionospheric effects for the two similar earthquakes

Is there a one-to-one correspondence between ionospheric anomalies and large earthquakes along Longmenshan faults?

On 12 May 2008, a destructive M8.0 earthquake struck Wenchuan County (31.0 N, 103.4E) in the Longmenshan fault zone of southwestern China. Five years later, on 20 April 2013, another terrible M7.0 earthquake struck Lushan County (30.3 N, 103.0 E) in the same fault area, only 87 km away from the epicenter of the Wenchuan earthquake. In this paper, an integrated wavelet analysis methodology is proposed to detect and diagnose ionospheric total electron content (TEC) anomalies related to seismic activities. Analytic wavelet transform is used to detect ionospheric perturbations, and then cross-wavelet analysis is used to diagnose ionospheric anomalies by gaining further insights into the dynamic relationship between the anomaly variability of ionospheric TEC and geomagnetic indices for the same set of observations. The results show that a significant ionospheric disturbance occurred on 9 May 2008 above the forthcoming epicenter, 3 days prior to the Wenchuan earthquake. However,we did not observe an ionospheric anomaly over the epicenter of the Ya’an earthquake during the 1 month period before the shock. Finally, we discuss the possible interpretations of the different seismo-ionospheric effects for the two similar earthquakes

Towards Advancing the Earthquake Forecasting by Machine Learning of Satellite Data

Earthquakes have become one of the leading causes of death from natural hazards in the last fifty years. Continuous efforts have been made to understand the physical characteristics of earthquakes and the interaction between the physical hazards and the environments so that appropriate warnings may be generated before earthquakes strike. However, earthquake forecasting is not trivial at all. Reliable forecastings should include the analysis and the signals indicating the coming of a significant quake. Unfortunately, these signals are rarely evident before earthquakes occur, and therefore it is challenging to detect such precursors in seismic analysis. Among the available technologies for earthquake research, remote sensing has been commonly used due to its unique features such as fast imaging and wide image-acquisition range. Nevertheless, early studies on pre-earthquake and remote-sensing anomalies are mostly oriented towards anomaly identification and analysis of a single physical parameter. Many analyses are based on singular events, which provide a lack of understanding of this complex natural phenomenon because usually, the earthquake signals are hidden in the environmental noise. The universality of such analysis still is not being demonstrated on a worldwide scale. In this paper, we investigate physical and dynamic changes of seismic data and thereby develop a novel machine learning method, namely Inverse Boosting Pruning Trees (IBPT), to issue short-term forecast based on the satellite data of 1371 earthquakes of magnitude six or above due to their impact on the environment. We have analyzed and compared our proposed framework against several states of the art machine learning methods using ten different infrared and hyperspectral measurements collected between 2006 and 2013. Our proposed method outperforms all the six selected baselines and shows a strong capability in improving the likelihood of earthquake forecasting across different earthquake databases

From visual comparison to robust satellite techniques: 30 years of thermal infrared satellite data analyses for the study of earthquake preparation phases

This review paper reports the main contributions and results achieved after more than 30 years of studies on the possible relationships among space-time variation of Earth’s thermally emitted radiation, measured by satellite sensors operating in the Thermal InfraRed (TIR) spectral range (8-14 m), and earthquake occurrence. Focus will be given on the different existing methods/models to: 1) discriminate a possible pre-seismic TIR anomaly from all the other TIR signal fluctuations; 2) correlate such anomalies with space, time and magnitude of earthquakes; 3) physically justify such a correlation

A comprehensive multiparametric and multilayer approach to study the preparation phase of large earthquakes from ground to space: The case study of the June 15 2019, M7.2 Kermadec Islands (New Zealand) earthquake

This work deals with a comprehensive multiparametric and multilayer approach to study earthquake-related processes that occur during the preparation phase of a large earthquake. As a case study, the paper investigates the M7.2 Kermadec Islands (New Zealand) large earthquake that occurred on June 15, 2019 as the result of shallow reverse faulting within the Tonga-Kermadec subduction zone. The analyses focused on seismic (earthquake catalogs), atmospheric (climatological archives) and ionospheric data from ground to space (mainly satellite) in order to disclose the possible Lithosphere-Atmosphere-Ionosphere Coupling (LAIC). The ionospheric investigations analysed and compared the Global Navigation Satellite System (GNSS) receiver network with in-situ observations from space thanks to both the European Space Agency (ESA) Swarm constellation and the China National Space Administration (CNSA in partnership with Italian Space Agency, ASI) satellite dedicated to search for possible ionospheric disturbances before medium-large earthquakes, i.e. the China Seismo-Electromagnetic Satellite (CSES-01). An interesting comparison is made with another subsequent earthquake with comparable magnitude (M7.1) that occurred in Ridgecrest, California (USA) on 6 July of the same year but in a different tectonic context. Both earthquakes showed anomalies in several parameters (e.g. aerosol, skin temperature and some ionospheric quantities) that appeared at almost the same times before each earthquake occurrence, evidencing a chain of processes that collectively point to the moment of the corresponding mainshock. In both cases, it is demonstrated that a comprehensive multiparametric and multilayer analysis is fundamental to better understand the LAIC in the occasion of complex phenomena such as earthquakes.This work was undertaken in the framework of Limadou-Science+ funded by ASI (Italian Space Agency). Part of the funds were also given by Working Earth (Pianeta Dinamico) Project. We thank GeoNet (NZ) for providing TEC data (we also thank Claudio Cesaroni and Luca Spogli for giving suggestions on TEC data analyses) and the Kyoto World Data Center for Geomagnetism (http://wdc.kugi.kyoto-u.ac.jp/) for providing geomagnetic data indices. ESA is thanked for providing the Swarm satellite data and the CNSA (Chinese National Space Administration) for providing CSES-01 satellite data

IMPORTANCE OF LITHOSPHERE-COVERSPHERE-ATMOSPHERE COUPLING TO EARTHQUAKE ANOMALY RECOGNITION

The GEOSS under construction is providing space-,aero-,ground/sea-based multiple observations on planet Earth for the seismogenic process monitoring and earthquake precaution. The stress enhancement and energy accumulation in seismic activity area change locally the physical parameters of lithosphere with the developing of a series of effects that can comprise most of the following ones: initial cracks, the fracturing of rockmass, the changing of electromagnetic properties, the decreasing of dielectric constant, the re-activation of P-holes, the leaking of poregas, and the rise of water-level. The physical states of coversphere and atmosphere are to be affected due to the lithosphere-coversphere-atmosphere (LCA) coupling, and the signals from the underground, surface, and atmosphere to satellites are to be changed with parameter anomaly. We suggested that the LCA coupling is important for understanding GEOSS observations, especially for earthquake anomaly recognition (EAR). Using deviation-time-space-thermal (DTS-T) method for EAR, three recent major earthquakes (2009 Italy L'Aquila earthquake, 2010 China Yushu earthquake and 2010-2011 New Zealand earthquake sequence) are taken as typical cases for analysis to the multi-parameters anomalies, preceding the shocking, with quasi-synchronism and geoconsistency. The specific LCA coupling effects related with the earthquakes are also discussed in brief

IMPORTANCE OF LITHOSPHERE-COVERSPHERE-ATMOSPHERE COUPLING TO EARTHQUAKE ANOMALY RECOGNITION

The GEOSS under construction is providing space-,aero-,ground/sea-based multiple observations on planet Earth for the seismogenic process monitoring and earthquake precaution. The stress enhancement and energy accumulation in seismic activity area change locally the physical parameters of lithosphere with the developing of a series of effects that can comprise most of the following ones: initial cracks, the fracturing of rockmass, the changing of electromagnetic properties, the decreasing of dielectric constant, the re-activation of P-holes, the leaking of poregas, and the rise of water-level. The physical states of coversphere and atmosphere are to be affected due to the lithosphere-coversphere-atmosphere (LCA) coupling, and the signals from the underground, surface, and atmosphere to satellites are to be changed with parameter anomaly. We suggested that the LCA coupling is important for understanding GEOSS observations, especially for earthquake anomaly recognition (EAR). Using deviation-time-space-thermal (DTS-T) method for EAR, three recent major earthquakes (2009 Italy L'Aquila earthquake, 2010 China Yushu earthquake and 2010-2011 New Zealand earthquake sequence) are taken as typical cases for analysis to the multi-parameters anomalies, preceding the shocking, with quasi-synchronism and geoconsistency. The specific LCA coupling effects related with the earthquakes are also discussed in brief.PublishedMunich, Germany1.10. TTC - Telerilevamento3.1. Fisica dei terremotirestricte