Geosites inventory of the northwestern Tabular Middle Atlas of Morocco   总被引：1，自引：0，他引：1  

Mohamed El Wartiti  Amina Malaki  Mohamed Zahraoui  Abdelilah El Ghannouchi  Felice Di Gregorio 《Environmental Geology》2008,55(2):415-422

Across the northwestern Tabular Middle Atlas of Morocco there are many examples of landscapes, rocks and fossils that provide key evidence of a particular moment or period in Earth history. Such Earth heritage sites are important for educating the general public in environmental matters. They also serve as tools for demonstrating sustainable development and for illustrating methods of site conservation as well as remembering that rocks, minerals, fossils, soils, landforms form an integral part of the natural world. The significance of certain sites for aesthetic or tourism reasons is obvious. There are numerous geosites, which could contribute to effective exploitation of geotourism, often in conjunction with ecotourism. The strategy employed to such sites involves close consultation with all communities in the vicinity of the respective geosite and is not only aimed at tourism and education, but also at sustainable improvement of the infrastructure of the people of this area. Geological heritage sites, properly managed, can generate employment and new economic activities, especially in regions in need of new or additional sources of income.  相似文献   

中国现代地图学发展的里程碑——中国国家地图集的特点与创新   总被引：1，自引：0，他引：1  

廖克 《地理科学进展》2001,20(3):201-208

本文阐述了国家地图集的重要性和中国国家地图集的编制历程，重点论述了中国国家地图集编制的特点与创新：①中国自然、人口、经济、社会与历史信息的完整汇编；②中国地学、生物学、环境科学、经济学与历史学研究成果的系统概括与总结；③国家地图集编制贯彻了“可持续发展战略”，突出了人与自然的关系；④国家地图集编制实现了由传统工艺向全数字化、自动化的根本变革，电子地图集与互联网地图形式更满足了信息社会的需求。中国国际地图集的完成，不仅具有重大的科学意义、应用价值与社会效益，而且全面推动当代中国地图学的发展。中国国家地图集这项20世纪中国科技界的重大创新成果，这部凝聚着中国两三代科学家与地图学专家智慧的地图集巨著，不仅在中国史无前例，而且在世界上也实属罕见。中国国家地图集代表当今中国地图学发展的最高水平，在国际上产生了很大影响，在各国国家地图中占有重要地位。中国国家地图集的完成对中国地图学的发展做出了历史性的巨大贡献，不愧为中国地图学发展的里程碑。  相似文献   

NEW RESULTS OF THE CHINA/KOREA JOINT STUDY ON OCEANOGRAPHY OF THE YELLOW SEA     

Liu Ruiyu  Zhao Yiyang  Weng Xuechuan  Gu Hongkan  Guo Yujie  Yang Jiming 《海洋与湖沼》1996,(6)

lCo~nofthe"booarePhicAtheoftheYthewsa"TheOceanographicAtlasoftheYellowSeahasbeencompiledbyChineseandKoreanscientistsbasedmainlyondataobtainedbyl992surveysandthoseaccumu-latedduringthepastyears,particularlythoseofl958-l988inphysicaloceanography,aswel1asthoseobtainedbytheChinesesideintheperiodl958-l959inmarinecheAnstryandbiology,andnewdataofrecenttenyearsinfisheryproductionbybothcountries-TheAtlasconsistsof5mainparts:(l)Marinegeologychartset,(2)Physicaloceanographychartset,(3)Marinechendst…  相似文献   

Le Toarcien inférieur du Haut Atlas de Todrha–Dadès (Maroc) : sédimentologie et lithostratigraphie     

Mohammed Ettaki  El Hassane Chellaï 《Comptes Rendus Geoscience》2005,337(9):814-823

The survey of sedimentological and lithostratigraphic Liassic facies of the Todrha–Dades area (southwestern part of the central High Atlas) permits to establish new data on the Tagoudite formation. Its environment deposit and its micropalaeontological content are evidenced in relation with the geodynamic evolution of the High Atlas Basin during the Early Toarcian. To cite this article: M. Ettaki, E.H. Chellaï, C. R. Geoscience 337 (2005).  相似文献   

Crustal structure under the central High Atlas Mountains (Morocco) from geological and gravity data   总被引：1，自引：0，他引：1  

P. Ayarza  F. Alvarez-Lobato  A. Teixell  M.L. Arboleya  E. Tesn  M. Julivert  M. Charroud 《Tectonophysics》2005,400(1-4):67-84

Seismic wide angle and receiver function results together with geological data have been used as constraints to build a gravity-based crustal model of the central High Atlas of Morocco. Integration of a newly acquired set of gravity values with public data allowed us to undertake 2–2.5D gravity modelling along two profiles that cross the entire mountain chain. Modelling suggests moderate crustal thickening, and a general state of Airy isostatic undercompensation. Localized thickening appears restricted to the vicinity of a north-dipping crustal-scale thrust fault, that offsets the Moho discontinuity and defines a small crustal root which accounts for the minimum Bouguer gravity anomaly values. Gravity modelling indicates that this root has a northeasterly strike, slightly oblique to the ENE general orientation of the High Atlas belt. A consequence of the obliquity between the High Atlas borders and its internal and deep structure is the lack of correlation between Bouguer gravity anomaly values and topography. Active buckling affecting the crust, a highly elevated asthenosphere, or a combination of both are addressed as side mechanisms that help to maintain the high elevations of the Atlas mountains.  相似文献   

Comportement d'une source karstique soumise à une sécheresse prolongée : la source Bittit (Maroc)     

Fouad Amraoui  Moumtaz Razack  Lhoussaine Bouchaou 《Comptes Rendus Geoscience》2004,336(12):1099-1109

The behaviour of a karstic spring (Bittit spring, Middle Atlas, Morocco) subjected to a prolonged drought (>20 yr), is analysed using spring hydrographs analysis methods and correlation and spectral methods. Two series of discharges, corresponding to a normal rainfall period and a drought period, are analysed. The results show that the karstic system is inertial, with very significant storage. However, in spite of the great regulating capacity of the storage, the long drought period significantly reduced the spring discharges, due to less diversified inputs, and to the karstic system storage depletion. To cite this article: F. Amraoui et al., C. R. Geoscience 336 (2004).  相似文献   

Structural and sedimentologic relations between the High and the Middle Atlas of Morocco during the Jurassic time     

R. Lwner  A. Souhel  D. Chafiki  J. Canrot  E. Klitzsch 《Journal of African Earth Sciences》2002,34(3-4)

The cartographic, sedimentologic and stratigraphic studies carried out on the Mesozoic deposits in the border zone between the Middle and the High Moroccan Atlas (regions of Naour and Aghbala) led us to specify the lithology of formations, the significant differences of thickness and the angular unconformities as well as stratigraphic hiatuses. All of this indicates a tectonic regime of transcurrent faults from the Bajocian–Bathonian period along the major fault zone “Aghbala–Afourer” in a N70° direction. A sinistral strike-slip movement along this major fault zone induced the development of folded and fractured zones in a N120° direction, which limited a small trough filled by the red continental formations. The whole system is covered thereafter by lower Cretaceous deposits.  相似文献   

Compressive palaeostress in the Mesozoic cover of the Tunisian atlas in relation with Africa–Europe moving together     

Houcine Chekhma  Mohsen Rabhi 《Comptes Rendus Geoscience》2008,340(6):414-419

The current structure of the central Tunisian Atlas fossilizes the different tectonic events that have succeeded and that have structured this region. The Lower Cretaceous of this sector reflects, through variations of thickness and facies, the importance of the tectonic activity during this period. The tectonic study detailed in this sector has revealed the existence of structures from the kilometric scale down to the metric one related to a compressive regime that has dominated the studied zone at least from the Upper Hauterivian until the Lower Aptian.  相似文献   

《汶川地震灾害地图集》的设计与编制     

曾文军  李维庆  刘增林 《四川测绘》2009,32(1):39-42

本文介绍了《汶川地震灾害地图集》的设计与编制，包括设计思想、图集基本内容、技术路线及工艺流程、内容及表现形式的设计、采用的新技术、图集的特色等。  相似文献   

A rapid method to map the crustal and lithospheric thickness using elevation, geoid anomaly and thermal analysis. Application to the Gibraltar Arc System, Atlas Mountains and adjacent zones   总被引：1，自引：0，他引：1  

J. Fullea  M. Fernndez  H. Zeyen  J. Vergs 《Tectonophysics》2007,430(1-4):97-117

We present a method based on the combination of elevation and geoid anomaly data together with thermal field to map crustal and lithospheric thickness. The main assumptions are local isostasy and a four-layered model composed of crust, lithospheric mantle, sea water and the asthenosphere. We consider a linear density gradient for the crust and a temperature dependent density for the lithospheric mantle. We perform sensitivity tests to evaluate the effect of the variation of the model parameters and the influence of RMS error of elevation and geoid anomaly databases. The application of this method to the Gibraltar Arc System, Atlas Mountains and adjacent zones reveals the presence of a lithospheric thinning zone, SW–NE oriented. This zone affects the High and Middle Atlas and extends from the Canary Islands to the eastern Alboran Basin and is probably linked with a similarly trending zone of thick lithosphere constituting the western Betics, eastern Rif, Rharb Basin, and Gulf of Cadiz. A number of different, even mutually opposite, geodynamic models have been proposed to explain the origin and evolution of the study area. Our results suggest that a plausible slab-retreating model should incorporate tear and asymmetric roll-back of the subducting slab to fit the present-day observed lithosphere geometry. In this context, the lithospheric thinning would be caused by lateral asthenospheric flow. An alternative mechanism responsible for lithospheric thinning is the presence of a hot magmatic reservoir derived from a deep ancient plume centred in the Canary Island, and extending as far as Central Europe.  相似文献