Stochastic Modeling of the Al Hoceima (Morocco) Aftershock Sequences of 1994, 2004 and 2016

Abstract

The three aftershock sequences that occurred in Al Hoceima, Morocco, in May 1994 (Mw 6.0), February 2004 (Mw 6.4) and January 2016 (Mw 6.3) were stochastically modeled to investigate their temporal and energetic behavior. A form of the restricted trigger model known as the restricted epidemic type aftershock sequence (RETAS) was used for the temporal analysis of the selected series. The best-determined fit models for each sequence differ based on the Akaike information criteria. The revealed discrepancies suggest that, although the activated fault systems are close (within 10 to 20 km), their stress regimes change and shift across each series. In addition, a stochastic model was presented to study the strain release following a specific strong earthquake. This model was constructed using a compound Poisson process and depicted the progression of the strain release during the aftershock sequence. The proposed model was then applied to the data. After the RETAS model was used to evaluate the behavior of the aftershock decay rate, the best-fit model was obtained and integrated into the strain-release stochastic analysis. By detecting the potential disparities between the observed data and model, the applied stochastic model of strain release allows for a more comprehensive examination. Furthermore, comparing the observed and expected cumulative energy release numbers revealed some variations at the start of all three sequences. This demonstrates that significant aftershock clusters occur more frequently shortly after the mainshock at the start of the sequence rather than if they are assumed to occur randomly.

Advancing Complexity Research in Earth Sciences and Geography

“…Alaei et al [7] propose a 2D pseudo-viscoelastic time-domain full-waveform inversion approach for the seismic imaging of complex velocity structures. Hamdache et al [8] employ a stochastic model entitled the restricted epidemic-type aftershock sequence (RETAS) to examine the similarities/differences in the three aftershock sequences that occurred in Al Hoceima, Morocco, in May 1994 (Mw 6.0), February 2004 (Mw 6.4) and January 2016 (Mw 6.3). In addition, in their study, Edigbue et al [9] develop a combined local and global optimization approach for jointly inverting two-dimensional direct current resistivity (DCR) and seismic refraction (SR) data for the purpose of reliably estimating the corresponding physical model parameters.…”

“…This book arises from a Special Issue of Applied Sciences that aimed to systematically examine the many complex phenomena that occur in earth sciences and geography, employing state-of-the-art methods for modeling complex data in order to invigorate research in earth sciences and geography, and to facilitate the further development of complexity science. Altogether, this Special Issue comprises 20 papers, contributed by researchers from all over the world and covering a range of diverse topics, including the encryption of digital elevation models [2], facies heterogeneity [3], the simulation of the snow cover process [4], the exploration of ice elevation change [5], earthquake and seismic activity [6][7][8][9], landslide susceptibility [10,11], the effect of reforestation [12], coordination between the supply and demand of ecosystem services [13], indoor positioning [14], public transport flow networks and retail store locations [15], the equality of healthcare facilities [16], recommender systems for e-retail [17], globalization [18], international trade and optimal industrial structure [19], risk analysis [20], and the quantification of political processes [21]. Below, I briefly explain the premise of each work, and when appropriate, highlight what could be further explored in future.…”

Identifying the Occurrence Time of the Destructive Kahramanmaraş-Gazientep Earthquake of Magnitude M7.8 in Turkey on 6 February 2023

“…Recently, the fractal characteristics of seismicity identified by the interevent times have found useful applications to cases of induced seismicity [69], see also [70], as well as in the case of the Anatolian region with implications for seismic hazards before and during the 2023 Kahramanmaraş seismic sequence [71]. Additionally, in forecasting fractal studies, see, e.g., [72,73], declustered catalogs are used. To date, NTA has not been applied to such catalogs.…”