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61.
Amal Enniouar Abdelouahed Lagnaoui Adnane Habib 《Proceedings of the Geologists' Association. Geologists' Association》2014
A Middle Jurassic site at Tafaytour area (Argana Basin, Morocco) with trackways of six large sauropod dinosaurs is regarded as having high scientific and touristic value. The new dinosaur track site is extremely vulnerable, and suffers from continuous degradation caused by weathering and human activity. Documentation and protection of this tracksite is still a necessity for its integration into local geotourism activities, where it may have a socio-economic impact on the local population. Taking into consideration many similar tracksites, and strata of great paleontological interest in Morocco, including the Tafaytour tracksite, the implementation of legislation for the protection of Morocco's geological heritage, especially the paleoichnological heritage, to protect against destruction, is strongly recommended. This is necessary to cement geoheritage impact, both for scientific reasons and to value add to the socio-economic activities of the local people. 相似文献
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Habib Belayouni Francesco Guerrera Manuel Martín-Martín Francisco Serrano 《International Journal of Earth Sciences》2013,102(3):831-855
The Numidian and Post-Numidian stratigraphy of the Tunisian Tell has been updated based on 16 stratigraphic sections belonging to the Massylian sub-domain of the Maghrebian Flysch Basin and to the External Domain. The new data concern detailed litho- and biostratigraphy, gaps, synchronous marker levels, lateral correlations, tectonic contacts, etc. The successions studied show many diachronous and unconformity boundaries delimiting sedimentary depositional sequences related to some tectonic/sedimentary processes. Two main Miocene sedimentary successions (Numidian and Post-Numidian) are recognized overlying the Sub-Numidian Succession (pre-Early Aquitanian) by new integrated (planktonic foraminifera and calcareous nannoplankton) chronostratigraphic analyses, allowing an update of the formations studied. The Miocene tectonic/sedimentary relationships and the timing of the deformation are summarized as follows: (1) the activation of a foredeep stage and a tectogenesis phase gives rise to an accretionary orogenic wedge during mainly the Early Miocene; (2) a late-orogenic phase is checked in the Late Burdigalian-Early Langhian characterized by a marine glauconitic terrigenous sedimentation; (3) a post-orogenic generalized phase is confirmed from the Middle Miocene on in shallow marine or continental sedimentation. These results show good correlation along the Maghrebian Chain and Betic Cordillera. Finally, a paleogeographic and geodynamic evolutionary model concerning the Miocene African Tunisian Margin is postulated. 相似文献
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Lepidocybium flavobrunneum (Smith, 1849) is widespread in warmer oceanic waters and has recently been recorded in the catches of tuna longline vessels in the New Zealand region. Twenty‐five specimens were caught at 31°46′‐32°03′S, 170°49′‐171°11′ E on 23–27 June 1979, thus extending the known range of the species to northern New Zealand. 相似文献
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Runoff and sediment yield modeling using SWAT model: case of Wadi Hatab basin,central Tunisia 总被引:1,自引:0,他引:1
This study presents an application of the model Soil and Water Assessment Tool (SWAT) to simulate daily and monthly water flow and sediment fluxes in the Wadi Hatab watershed (2200 km2) located in central Tunisia. The study basin is characterized by a significant climatic contrast, abrupt topography, and soil fragility, resulting thereby in flash floods and important water erosion rates. This alarming situation requires urgent interventions in order to preserve water and soil resources, implying the need for a decision tool for proper integrated management of the watershed. The model was calibrated and validated based on a comparison of simulated and observed flow rates at the basin outlet (hydrometric station Khanguet Zazia), during the periods 1987–1988 and 1989–1990, respectively. The comparison was based not only on visual inspection of the agreement between observed and simulated time series, but also on statistical parameters. Indeed, for the daily time step application, the Nash—Sutcliffe efficiency (NSE) values were 0.52 and 0.61, and the coefficient of determination (R2) was 0.54 and 0.61 for calibration and validation, respectively. As for the monthly time-step application, the obtained NSE values were 0.67 and 0.89 while R2 values were 0.83 and 0.87 for calibration and validation, respectively. This clearly shows the reasonably good agreement between simulated and observed flow rates. In terms of erosion, the model gave sediment yield values ??of 1.15 and 5.37 t/ha/year during the periods of calibration and validation, respectively. 相似文献
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Mahmoud Fatemiaghda Habib Shahnazari Mehdi Talkhablu 《Marine Georesources & Geotechnology》2017,35(7):986-998
Aggregate crushing is a phenomenon occurring in carbonate soils under shear and compressive loads resulting in settlement of the offshore structures such as piers, bridges, waterfronts, wharfs, and oil and gas extraction platform foundations. Therefore, it is of significant importance to address the above-mentioned issue through a comprehensive study. In the present research, the texture of carbonate soil in south Iran coasts and its effect at high hydrostatic pressure (2?MPa) on aggregate crushing was studied. The physical properties of coastal soils, such as the effective grain size, shape index, and angularity were then characterized to investigate their effect on grain crushing grade. The results showed that the effective grain size, shape index, angularity, and calcium carbonate content are the main parameters affecting the crushing of grains and consequently settlement of marine soils. Based on the above parameters, a relationship is proposed to estimate grain crushing in carbonate soils. 相似文献
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Sadeghi Maedeh Jandaghi Alaee Farshid Akbarzadeh Bengar Habib Jafari Abouzar 《Bulletin of Earthquake Engineering》2022,20(11):6075-6107
Bulletin of Earthquake Engineering - Although self-centering rocking walls have shown acceptable performance in decreasing downtime, repair cost, and continuous serviceability, their energy... 相似文献