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Contribution of Geomatics and Remote Sensing to Environmental Study in the Cretaceous Basin of Errachidia-Boudenib (Morocco)

100%

Mehdaoui R. , Mili E.-M. , Ousmana H. , Said B. A. , El Khamal Y. , Aziz H. , El Fakir R.

Ecological Engineering & Environmental Technology

2023

tom Vol. 24, iss. 1

196--206

The present study aims at mapping areas vulnerable to water erosion based on the Priority Activity Program/Regional Activity Center (PAP/CAR) model guidelines, geomatics, remote sensing, and GIS in the Errachidia-Boudenib Cretaceous basin. This basin is located in south-eastern Morocco and covers an area of 13 000 km2, the basin is 320 km long and 75 km wide. The method of estimating water erosion is composed of three phases; a predictive phase consisting of a mapping of predisposing factors such as slope, substrate, and/or soils and vegetation cover, a descriptive phase based on the mapping of actual erosion, and an integration phase to arrive at the identification and evaluation of the erosion risk. The mapping of areas vulnerable to water erosion indicates that 70% of the studied basin has low erodibility and 22% is notable, while only 8% has high to very high erodibility. The areas most affected by degradation are located at the end of the basin and correspond to lands with steep slopes (>35%). Consequently, this study has allowed us to locate certain sectors and roads that may be affected by this type of erosion, namely the mountainous areas of the High Atlas and roads numbered R13, R601, R 703, and P7106.

Identification and evolution of the Turonian aquifer case study: Cretaceous basin of Béchar, southwestern Algeria

100%

Sadat S. , Mansour H. , Mekkaoui A. , Merzougui T.

Journal of Water and Land Development

2020

tom no. 46

190--199

Faced with the challenges of sustainable groundwater resource management in the arid zone, the identification of reserves and their monitoring have become vital. This paper aims to identify the Turonian aquifer in the Cretaceous Béchar basin, and calculate its transmissivity, permeability and storage coefficient, as well as its evolution over time. This Turonian aquifer is characterized by marine limestones (gentle dip shelters 45° to the North and 5° to 10° to the South). Pumping tests revealed a transmissivity T of 10–4 to 10–2 m2·s–1, a permeability K of 10–6 to 10–4 m·s–1 and a storage coefficient S of approximately 10–3. Two piezometric campaigns, carried out between (1976–2018), show a converging and constant flow direction from the North–East to the South–West and from the North–West to the South–East towards the outlet of the basin. Decreased values were observed in the North and South–West borders due to isopiezometric lines. However, this water table is not in a stationary state, it shows seasonal and interannual fluctuations in relation to the variable rainfall and the exploitation rate. In terms of facies, the projection of the two hydrochemical campaigns, during 1976 and 2018 on the Piper diagram, did not show any significant evolution, they are concentrated in the chlorinated and sulphated calcium and magnesium facies.

Identification and evolution of the Turonian aquifer case study: Cretaceous basin of Béchar, southwestern Algeria

86%

Sadat S. , Mansour H. , Mekkaoui A. , Merzougui T. , Sadat S. , Mansour H. , Mekkaoui A. , Merzougui T.

The Czertezik Succession in the Pieniny National Park (Pieniny Klippen Belt, West Carpathians): stratigraphy, tectonics, palaeogeography

72%

Birkenmajer K.

2007

tom Vol. 127

7-50

The stratigraphic column of the Czertezik Succession (Pieniny Klippen Belt, West Carpathians) includes Upper Liassic through Upper Cretaceous rock units. The succession crops out in several tectonic windows from below the Pieniny Nappe and/or the Branisko Nappe which were thrust over the Czertezik Unit during Laramian folding of the Klippen Belt. Lithological development and succession of strata of the Czertezik Unit in these windows prove that its original sedimentary zone was a direct southern continuation of the Czorsztyn one. In the present author's opinion, contrary to Wierzbowski et al. (2004), the Czertezik Succession in the territory of Poland lacks the Bajocian-Callovian ammonitico rosso unit = the Niedzica Limestone Formation. The Czorsztyn Limestone Formation (Kimmeridgian, also ammonitico rosso facies) distinguished by the present author in the Czertezik Succession at Czertezik and Pieniński Stream (Pieniny Range), and at Wysoka Mt (Little Pieniny Range), attributed by Wierzbowski et al. (2004) to the "Niedzica Limestone Formation", did not yield any age-diagnostic fossils to support their change of its Kimmeridgian (resp. Oxfordian-Kimmeridgian) age to an Upper Bajocian-Callovian one. This limestone occurs always above, and not below the radiolarite horizon (Czajakowa Radiolarite Fm.). In the present author's opinion, two klippes with fossiliferous Niedzica Limestone Formation described by Wierzbowski et al. (2004) from Litmanová and Milpoš, East Slovakia, do not represent the Czertezik Succession but are typical examples of the Niedzica Succession. A palinspastic-sedimentological model proposed in this paper shows probable Middle Jurassic palaeogeographic position of the very discontinuous sedimentary area of the Niedzica Succession, between larger submarine crinoid limestone fans developed in the Czorsztyn and Czertezik sedimentary zones.