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Abstract—The effect of water saturation of the medium on the property of earthquakes to trigger other earthquake shocks (earthquake productivity) is studied using the long-term seismological observations and water inflow monitoring data in the Khibiny massif ore deposits. The analysis indicates that water saturation of the medium is a significant factor affecting the productivity of earthquakes. [ABSTRACT FROM AUTHOR]

The main disadvantages of selected elements of seismicity modeling for composing the General Seismic Zoning maps are considered in the framework of a probabilistic approach. We proposed a method that should provide more precise assessment of probable future seismicity after the improvements of the disadvantages. A stochastic seismicity model is suggested for the first time as a synthetic earthquake catalog, which is generated for an arbitrary conditional period and which reproduces the properties of the catalog of factual earthquakes including spatiotemporal grouping. The verification method of seismicity models is suggested to check the correspondence of the models to the primary data and the assessment of the predictive efficiency of the models and to compare various models based on these characteristics. [ABSTRACT FROM AUTHOR]

Abstract—This paper analyzes the use of the automated aftershock hazards assessment system (AFCAST) through the example of a series of aftershocks of the Mw 7.8 earthquake in Turkey of February 6, 2023 (the Pazarcik earthquake). The paper presents automated estimates of the aftershock activity area, the magnitude of the strongest aftershock, and the duration of the hazardous period, yielded using data on the main shock and on the first aftershocks. [ABSTRACT FROM AUTHOR]

For the first time, a numerical comparison of the General Seismic Zoning (GSZ) maps with the effect of earthquakes that actually occurred after the publication of the maps was carried out. The area of zones of expected intensity on the GSZ map is compared with the area of isoseists from actual earthquakes. It turned out that the isoseist area is on average by an order less than expected according to the GSZ. This paper describes possible reasons for such an overestimation and proposes ways to improve seismic hazard assessments. [ABSTRACT FROM AUTHOR]

Mechanisms of stress transfer and probabilistic models have been widely investigated to explain earthquake clustering features. However, these approaches are still far from being able to link individual events and to determine the number of earthquakes caused by a single event. An alternative approach based on proximity functions allows us to generate hierarchical clustering trees and to identify pairs of nearest-neighbours between consecutive levels of hierarchy. Then, the productivity of an earthquake is the number of events of the next level to which it is linked. Using a relative magnitude threshold Δ M to account for scale invariance in the triggering process, we show that the Δ M -productivity attached to each event is a random variable that follows an exponential distribution. The exponential rate of this distribution does not depend on the magnitude of triggering events and systematically decreases with depth. These results could now be used to characterize active fault systems and improve epidemic models of seismicity. [ABSTRACT FROM AUTHOR]

The paper addresses the study of the ability of mining-induced earthquakes to generate successive shocks. Based on the example of the Khibiny natural–technogenic system, it is shown that the number of the initiated shocks (the productivity) has the exponential distribution with the form independent on the magnitude and depth of the events. This result is consistent with the similar productivity law previously established for the tectonic earthquakes on the global and regional levels, expanding the validity of this law to the lower energy scales of seismic events ~104 J (M ≥ 0). [ABSTRACT FROM AUTHOR]

The paper summarizes the results of the experiment on advance earthquake forecasting using the Reverse Tracing of Precursors (RTP) algorithm based on the phenomenon of the increase in seismicity correlation range before large earthquakes. During the test period from 2003 to 2019, 28 strong earthquakes occurred in five regions of the world, and 23 of these events fell within the regions and alarm intervals diagnosed by the algorithm. The probability of occasional success in the regions was at most 30% and averaged about 15%. These results confirm the efficiency of the RTP algorithm. The tests have also shown a high degree of nonrandom coincidence of the strong earthquakes and their preceding indicators in the form of the increase in the correlation range—the chains of the earthquakes. [ABSTRACT FROM AUTHOR]

This paper considers the global statistics of times of largest aftershocks relative to the times of the corresponding main shocks. A large data set was used to show that the time-dependent distribution of largest aftershocks obeys a power law distribution. This is analogous to the Omori law for the sequence of all aftershocks. It is also shown that the times of the second, etc., largest aftershocks obey the same distribution. Thereby, we have confirmed the hypothesis that the times and magnitudes in an aftershock sequence are independent and make a good case for the Reasenberg–Jones representation of the aftershock process as a superposition of the Omori–Utsu law and the Gutenberg–Richter relation. Events that are smaller than the largest in an aftershock sequence show no delay relative to the largest event; this rejects the idea of the aftershock process as a direct failure cascade involving gradual transitions from larger to lesser scales, which imposes certain restrictions on the widely popular stochastic models of aftershock generation as branching processes. The above result is important in practice for prediction of aftershock activity and for assessing the hazard of large aftershocks. [ABSTRACT FROM AUTHOR]

The geometry of supposed coupling zones in the Kamchatka subduction zone is determined by the earthquake size distribution based on ealier revealed relationship between its shape and rate of inelastic deformations. In the areas of higher aseismic slip, a break of linearity in earthquake size distribution is observed owing to the deficit of large earthquakes. Zones of higher coupling between the oceanic and continental plates are characterized by an excess of large earthquakes and an inverse bend in the earthquake size distribution. The mapping results of the bend value agree with the coupling zones distinguished from satellite geodetic data and inversion of marigrams. [ABSTRACT FROM AUTHOR]