Hallal Nassim

Center for Research in Astronomy and Astrophysics Geophysics | CRAAG · Aléas et risques géologiques

This paper presents a comprehensive seismic hazard assessment of the Mila earthquake epicentral area that occurred on August 7, 2020 (Mw 5.0) in northeast Algeria. The analysis emphasizes the environmental factors that likely played a crucial role in amplifying the earthquake’s damaging impacts on the region. This interdisciplinary methodology enco...

Landslides are the main gravitational phenomena in the Neogene basins of Algeria. This feature is mainly favored by the lithological nature of the fill materials, the climate, and the slope morphology. They are known for their high residential concentration and urban development. For better management and planning of future projects in landslide-pr...

Natural risks comprise a whole range of disasters and dangers, requiring comprehensive management through advanced assessment, forecasting, and warning systems. Our specific focus is on landslides in difficult terrains. The evaluation of landslide risks employs sophisticated multicriteria models, such as the weighted sum GIS approach, which integra...

In Algeria, the north part is known by complex geological structures with a very important topography. This area is characterized by medium to high seismic activity, with a relatively high magnitude Mw of 5–7 and a maximum intensity of XIII. In the North-East, the Mila region, which is part of the North-East Algeria Alpine Chain, is exposed to this...

The coastal aquifer of Ras Jebel is located in the northeastern governorate of Bizerte. It is formed by a Mio–Plio-quaternary geological structure. The region of Ras Jebal is considered an important agricultural centre due to intensive groundwater exploitation. This overexploitation results in a decrease in piezometry and an increase in salinity. T...

Natural risks encompass a range of disasters and dangers, requiring comprehensive management through assessments, anticipations, and advanced alert systems. Our specific focus is on landslides in challenging terrains. The evaluation of landslide risks employs sophisticated multicriteria models, such as the weighted sum approach, integrating qualita...

About 270 landslides have been triggered in the Mila region (northeast Algeria) linked to the 7 August 2020 Mw 5 earthquake, but they have not been analyzed and mapped throughout the region. As a consequence, the potential link between the earthquake, faults, and the set of large landslides registered subsequently in the same region has not yet bee...

Here, we present a seismic hazard evaluation for the August 7, 2020 (Mw 5.0) Mila earthquake that occurred in northeast Algeria. The study addresses the environmental factors that could contribute significantly to the highly damaging impact of this event. The following aspects were included in an interdisciplinary methodology that was adopted: the...

The specific lithology of the southern part of Bejaia city represents a major limitation to urban settlement and expansion. This is partly due to landslides that tend to affect this region. To date, one of these landslides in this region has occurred in the Targa Ouzemour area, where the damage extended approximately six hectares. The main purpose...

The preservation of historical heritage buildings against natural hazards, especially seismic risk, is extremely challenging. The earthquake is, of all the cataclysms, the one that engages the most deeply the responsibility of the State. Countries presenting medium to moderate seismic risk, like Northeast of Algeria, want to protect this particular...

On August 7th, 2020, a magnitude Mw = 5.0 earthquake shook 5 km north of Mila city center, northeast of Algeria, causing substantial damage directly to structures, and indirectly from induced impacts of landslides and rock falls, ultimately disrupt to everyday civilian life. Given the recent significant seismic occurrences in the region, a detailed...

In the Mila region (NE of Algiers), the problem of soil instabilities is mainly related to continental and marine sedimentary deposits. This area is known by older landslides triggered by the interaction of several causes and triggering factors (geology, climate, seismicity, etc.). The main objective of this study is to map Mila landslides caused b...

The Neogene basins are well known for their high susceptibility to landslides. This feature is mainly favoured by the lithological nature of the filling materials and slope morphology. This study proposes a combined frequency ratio and limits equilibrium methodology to perform a regional analysis of slope stability in the Neogene basin of Aomar Ben...

On August 7th, 2020, a magnitude Mw = 5.0 earthquake shook 5 km north of Mila city center, northeast of Algeria, causing substantial damage directly to structures, and indirectly from induced impacts of landslides and rock falls, ultimately disrupt to everyday civilian life. Given the recent significant seismic occurrences in the region, a detailed...

This paper defines the dynamic analysis and geometric demonstration of movement transmission and the dynamic soil-structure interaction using two different approaches: the finite component process and the limit component approach (EM). This mathematical process is an influential geometric approach right for dynamic tasks. In this item, we used very...

The aim of this study is to conduct a probabilistic seismic hazard analysis and spatial variation of seismic hazard at the surface level for Northeast of Algeria, covering 4°E–9°E, 33°N–38°N. The most recent peak ground acceleration (PGA) attenuation relationship, along with the updated seismic catalog and the best knowledge on the seismic activity...

We have kindly received the comments by Ham-dache and Pelàez on our published paper (Hamidatou et al. 2019); This article will give us the opportunity to provide more explanation and clarifications on the methodology followed during our work. We find these comments and critiques helpful for our future works. However, most of them were generated fro...

A moderate earthquake (ML 5.0) occurred in the Oued Djer region of the Tell Atlas, Algiers Province, Central Algeria, on 02 January 2018 (20:59:00 UTC), 10 km southwest of Mitidja Basin (36.39° N, 2.54° E), at a depth of 4 km. The earthquake is significant because it occurred immediately south of the epicentral area of the 1988 MS 5.4 Oued Djer Ear...

Nowadays information about geotechnical parameters and future stability of soil is highly demanded by geotechnical laboratories and companies. In this context, the LCTP has carried out a general study on landslides and unstable zones threatening the national and Wilaya network roads, by producing movement zoning maps of the 17 wilayas positioned in...

In the geotechnical field it is possible to encounter very complex phenomena, which are hardly analyzed by analytical methods based on physical laws. Classical methods, such as empirical correlations have too little power to efficiently generate them. Nevertheless, geotechnical engineers have successfully adopted different experimental methods of i...

In the geotechnical field it is possible to encounter very complex phenomena, which are hardly analyzed by analytical methods based on physical laws. Classical methods, such as empirical correlations have too little power to efficiently generate them. Nevertheless, geotechnical engineers have successfully adopted different experimental methods of i...

A better understanding of the spatiotemporal evolution of landslides in urban zones is a key factor in assessing the risk of future slides within these areas. The El Biar landslide, located around the center of Algiers city, is one of the most important landslides in the region. It occurs mostly within a high strategic zone between schools, embassi...

Dans la région d’Aokas (w. Bejaïa), les falaises du massif calcaire dolomitique qui borde la ville du côté ouest ont enregistré plusieurs phénomènes spectaculaires de type chute de bloc et éboulement-écroulement. Les plus importants date de 2005, 2014 et 2015. Ce massif est affecté par plusieurs failles, la plus importante est subverticale, transpr...

Un mouvement de terrain est apparu sur un talus situé à proximité de la route nationale RN25 dans la commune d'Aomar (Wilaya de BOUIRA), appelé talus d'Aomar (fig.1). Le site du glissement concerné par la présente étude fait partie du bassin post-nappes d'Aomar-Ben-Haroun d'âge miocène supérieur. Figure1. Carte de localisation de la commune d'Aomar...

Dans la région d'Aokas, se trouve l'une des merveilles sites géologiques de la Wilaya de Bejaïa, c'est la Grotte Féerique du Cap Aokas. Ce lieu est l'identité de toute une station touristique dans la région. Découverte en 1963 par des ouvriers aux cours des travaux de réalisation du tunnel dans le Cap Aokas, duquel la ville tire son nom Aokas signi...

The Cape Aokas situated in the oriental coastal region of Béjaïa city (Algeria). The cape takes its origin from the babor mountain chain to the Mediterranean Sea along the Aokas city. Its relief is characterized by abrupt slopes. On May 9th, 2005 rocks fall in large mass (20,000 to 30,000m3) from one of the walls constituting the cape, blocked traf...

This article contributes to the analysis of the various factors that interact in triggering and reactivating of landslides in Béjaïa city and its eastern coastal region. These factors are associated with lithologic nature of the various geological formations outcropping, morphology and its evolution during the Quaternary period, rainfall patterns a...

The oriental coastal region of Béjaïa city is situated in the mountainous chain of the Babors. The relief is steep as well as slopes which are very abrupt. In the North, the Babors coastal massif dominates the Mediterranean Sea forming the Cap of Aokas and Djebel Djamaa N’ sia in the city of Melbou. The recent realized tunnels (T1, T2) cross the li...

Underground work’s constructions and design techniques depend closely on the geological environment. The properties of the rock mass influence directly on the various steps of their realization so that geological and geotechnical studies become an absolute necessity to characterize the rock mass and to control the imposed constraints. At the end, w...