Using modern seismological data to reveal earthquake precursors

The results of earthquake prediction largely depend on the quality of data and the methods of their joint processing. At present, for a number of regions, it is possible, in addition to data from earthquake catalogs, to use space geodesy data obtained with the help of GPS. The purpose of our study is to evaluate the efficiency of using the time series of displacements of the Earth’s surface according to GPS data for the systematic prediction of earthquakes. The criterion of efficiency is the probability of successful prediction of an earthquake with a limited size of the alarm zone. We use a machine learning method, namely the method of the minimum area of alarm, to predict earthquakes with a magnitude greater than 6.0 and a hypocenter depth of up to 60 km, which occurred from 2016 to 2020 in Japan, and earthquakes with a magnitude greater than 5.5. and a hypocenter depth of up to 60 km, which happened from 2013 to 2020 in California. For each region, we compare the following results: random forecast of earthquakes, forecast obtained with the field of spatial density of earthquake epicenters, forecast obtained with spatio-temporal fields based on GPS data, based on seismological data, and based on combined GPS data and seismological data. The results confirm the effectiveness of using GPS data for the systematic prediction of earthquakes.

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Active Fault Systems in the Inner Northwest Apennines, Italy: A Reappraisal One Century after the 1920 Mw ~6.5 Fivizzano Earthquake

Geosciences ◽

10.3390/geosciences11030139 ◽

2021 ◽

Vol 11 (3) ◽

pp. 139

Author(s):

Giancarlo Molli ◽

Isabelle Manighetti ◽

Rick Bennett ◽

Jacques Malavieille ◽

Enrico Serpelloni ◽

...

Keyword(s):

Large Scale ◽

Active Fault ◽

Active Faults ◽

Dense Network ◽

Earthquake Fault ◽

Slip Rates ◽

Fault Systems ◽

Seismological Data ◽

Seismogenic Faults

Based on the review of the available stratigraphic, tectonic, morphological, geodetic, and seismological data, along with new structural observations, we present a reappraisal of the potential seismogenic faults and fault systems in the inner northwest Apennines, Italy, which was the site, one century ago, of the devastating Mw ~6.5, 1920 Fivizzano earthquake. Our updated fault catalog provides the fault locations, as well as the description of their architecture, large-scale segmentation, cumulative displacements, evidence for recent to present activity, and long-term slip rates. Our work documents that a dense network of active faults, and thus potential earthquake fault sources, exists in the region. We discuss the seismogenic potential of these faults, and propose a general tectonic scenario that might account for their development.

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Alarm systems based on a pair of short-term earthquake precursors

Bulletin of the Seismological Society of America ◽

10.1785/bssa0780041538 ◽

1988 ◽

Vol 78 (4) ◽

pp. 1538-1549

Author(s):

Giuseppe Grandori ◽

Elisa Guagenti ◽

Federico Perotti

Keyword(s):

Statistical Analysis ◽

Active Region ◽

Southern California ◽

Main Shock ◽

Weak Shock ◽

Earthquake Precursors ◽

Alarm System ◽

Short Term ◽

Alarm Systems

Abstract A statistical analysis of the foreshock-main shock correlation for a seismically active region in Italy is presented. It is found that the probability that a weak shock be followed within 2 days by a main shock is of the order of 2 per cent, while the probability that a main shock be preceded by a foreshock is of the order of 50 per cent. These results are quite similar to those found by L. Jones (1985) for southern California. The effectiveness of alarm systems based on a pair of short-term earthquake precursors is then analyzed. In particular, the analysis shows under what conditions the precursor, consisting of potential foreshocks, could be combined with another precursor to provide a reasonably effective alarm system.

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How to Predict Earthquakes by Using Simple and Reliable Method? Peru, Chile, Italy, Greece, New Zealand, Andaman and Nicobar Islands, India

Austin Environmental Sciences ◽

10.26420/austinenvironsci.2021.1059 ◽

2021 ◽

Vol 6 (2) ◽

Author(s):

Prakash Pillai S ◽

Keyword(s):

Centrifugal Force ◽

Reliable Method ◽

Orbital Motion ◽

Earthquake Precursors ◽

Generation Process ◽

Tectonic Plates ◽

The Earth ◽

Eruption Precursors ◽

Weather Anomalies ◽

Seasonal Weather

This paper intended to highlight the simple, quick and reliable method to detect impending earthquake�s location. Volcanic eruption precursors are originated only around the volcanos, like that the onshore earthquake precursors are originated only from earthquake epicenter zones. Epicenter zones are earthquake zones, a little variation of fault zone, it comprises movable tectonic plates. Due to the orbital motion of the earth, centrifugal force generated, this centrifugal force is the major driving force of tectonic plates. The position of the orbital motion of the earth generated seasonal variations/atmospheric weather anomalies as onshore earthquake precursors and earthquakes, year after year repeating at same places. The generation process of seasonal weather anomalies is the part of generation process of earthquakes at epicenter zones. Both seasonal weather anomalies and seismic anomalies are not continued all through the year at same places. When earth comes to particular position, tectonic plates of particular epicenter zones are set to more active and becomes unstable epicenter zones, causes identifiable, observable, recordable and testable onshore earthquake precursors 1-15 days prior to earthquakes occur.

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Brief communication "On the recent reaffirmation of ULF magnetic earthquakes precursors"

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-2193-2011 ◽

2011 ◽

Vol 11 (8) ◽

pp. 2193-2198 ◽

Cited By ~ 19

Author(s):

F. Masci

Keyword(s):

Geomagnetic Activity ◽

Geomagnetic Field ◽

Earthquake Precursors

Abstract. Hayakawa et al. (2009) and Hayakawa (2011) have recently reviewed some "anomalous" ULF signatures in the geomagnetic field which previous publications have claimed to be earthquake precursors. The motivation of this review is "to offer a further support to the definite presence of those anomalies". Here, these ULF precursors are reviewed once again. This brief communication shows that the reviewed anomalies do not "increase the credibility on the presence of electromagnetic phenomena associated with an earthquake" since these anomalous signals are actually caused by normal geomagnetic activity. Furthermore, some of these ULF precursors have just been rebutted by previous publications.

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