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Lunar rilles are any of the long, narrow depressions on the surface of the Moon. These structures have different characteristics, which are related to their origin. Here, a classification of the lunar rilles in different groups with similar morphometric features and likely the same formation mechanisms is proposed. The detection, classification and mapping of lunar rilles has been achieved in two quadrants of the northern hemisphere, which are located between -90°E to 90°E longitude and 0°N to 60°N latitude. For the detection and mapping of rilles, we used images from the Lunar Reconnaissance Orbiter Camera (LROC) [1] which have a resolution of 100 m/pixel and the DEM from Lunar Orbiter Laser Altimeter (LOLA) [2] with a resolution of 6 m/pixel. Lunar rilles include generic sinuous rilles (SR), cracks on lava deposits (CL), surface lava flows (LF), subsurface lava tubes or catena (crater chains, CC) and tectonic structures (TS). For each type of the classified structures, morphologic parameters, i.e. length, width, perimeter, area, depth, longitude and latitude have been measured in order to allow a better understanding of how these features formed [3]. For those sinuous rilles classified as remnants of shallow lava channels or subsurface collapsed lava tubes, morphometric analysis included the extraction of the sinuosity index and of the regional slope and azimuth. This work is born inside an international cooperation between Italy and China called "Moon Mapping project" for the cooperation between Italian and Chinese college students [4].

In the framework of several projects sustained by the Regional Sardinian Government Laws no. 43 (28/09/1990) and no. 19 (11/04/1996), research groups of the University of Cagliari (Sardinia, Italy) and of the University Mohamed V-Agdal of Rabat (Morocco) have started a series of preliminary geo-environmental studies in the basin of the Oued Sebou. An area of almost 1000 square km around the famous city of Fes has been studied, using satellite images and two ground surveying campaigns. These surveys aim to define the geological and structural settings, the vegetation and land use, in order to define the landscape units and to select the areas of major hydrogeological and geo-environmental risk. The satellite data used are the LANDSAT TM5 images taken on the 9th of October 1997. These images have been analysed to obtain the different bases for further thematic mapping, resulting in the geo-environmental map of the area around Fes that constitutes an up-to-date representation of the geological and environmental state of the territory and a useful instrument for further risk assessment and urban and territorial planning.

Geomorphological heritage is a widely used term in European and North-American countries but is still scarcely mentioned in Africa. Nevertheless, the attractiveness of the African countries is often intimately connected to its breathtaking and endless geological landscapes. Morocco is one of those countries that has the widest diversity in landscapes and landforms, ranging from the Mediterranean and Atlantic coasts over the Rif, Middle Atlas, High Atlas and Anti-Atlas mountain chains to the great rocky and sandy deserts in the South. A wide variety of geological units hosting different types of important economic mineral deposits cover a temporal range from Late Precambrian to Quaternary. A detailed geomorphological study has been carried out in the region of Ifrane and Azrou (Middle Atlas, Central Morocco) using a combination of high resolution satellite data and direct field observations integrated by geological maps and scientific literature. In order to describe and evaluate the geomorphological heritage of this area forty geomorphosites have been selected comprising springs, karst landforms (polje, dolines, caves, sinkholes, stone forests, cryptokarstic dolines), carbonate depositional landforms (travertines and waterfalls), fluvial landforms (meanders, canyons, palaeo-valleys, etc.), structural landforms (triangular facets, hogbacks, cuestas, residual outcrops, etc.) and volcanic landforms (volcanoes, caldeira, pyroclastic cones, lava tube). The results of this research have been summarised in a thematic map, representing the geomorphosites related to various landscape units.

The concept of geomorphosites is relatively recent (Panizza, 2001), finding application in many European nations, but in Africa much research on geomorphological heritage has still to be done. In the framework of some Projects financed by the Sardinian Government (Regional Law 19/1996, cooperation with developing countries) a research collaboration has been established between the Department of Earth Sciences of Cagliari University (Italy) and the Laboratory of Applied Geology of the Science Faculty of the University Mohammed V-Agdal of Rabat (Morocco). The research group has started studying landscape units, geomorphology, geomorphosites and geological heritage in different North-African regions, with the aim of drawing thematic geomorphological maps. The choice of these arguments as main objectives of this research is determined by the absolute lack of specific researches on these topics in Morocco. Furthermore, the very interesting landscapes, very rich in geological and geomorphological sites, deserve to be better known, safeguarded and valorised. This research has allowed to realise the first example of Landscape and Geomorphosites Map in Morocco, compiled for the area of Ifrane and Azrou in the Middle Atlas (Central Morocco). This region is already inserted in the classical tourist routes that connect Fes and Meknès with the South of Morocco and this fact, together with its geological and geomorphological variety, has suggested its selection for this type of applied research. The research carried out by means of the analysis of airborne- and satellite images and direct field observations have brought to the recognition of 14 landscape units in which 42 geomorphosites have been selected. These geomorphosites comprise springs, karst landforms (polje, dolines, caves, sinkholes, stone forests, cryptokarstic dolines), carbonate depositional landforms (travertines and waterfalls), fluvial landforms (meanders, canyons, palaeo-valleys, etc.), structural landforms (triangular facets, hogbacks, cuestas, residual outcrops, etc.), volcanic landforms (volcanoes, caldeira, pyroclastic cones, lava tube) and two geo-botanical sites. The results of this research have been summarised in a geomorphological map, representing the various landscape units and the geomorphosites, and comprises a proposal for the valorisation of the geomorphological heritage by means of six of itineraries. The Map, constructed upon a Landsat ETM+ image, is completed with some geological sketch maps and sections and several photographs of the geomorphosites with their scientific explanation.

Questo lavoro ha consentito di realizzare una Carta dei Geomorfositi dell’area di Azrou-Ifrane nel Medio Atlante, elaborata su un’immagine Landsat ETM+. La Carta riassume le conoscenze sulle valenze geomorfologiche di questo interessante e suggestivo territorio classificate con criteri scientifici ma allo stesso tempo in maniera semplice e chiara, e può fungere da base per ulteriori ricerche in quest’ambito in altre aree marocchine.

Tozeur is the most important tourist town of south-western Tunisia, situated in between the two salt lakes Chott El Djerid to the south and Chott El Gharsa to the north. This area is known for its luxuriant oasis in the middle of the desert (Tozeur, Gafsa, Nefta etc.), the mountain chains to the north close to the border with Algeria with its villages and waterfalls (Tameghza, Chebìka, Midès), the mountain chain east of Tozeur (Jbel Morra etc.) with its arid canyons, and the wide salt plains (Chotts). Tourists usually visit the region rapidly without staying overnight, overlooking and ignoring the great geomorphologic and geological interesting places and landscapes. Therefore, in the framework of a Research Project performed by the Department of Geology of the University of Cagliari in collaboration with the Institut des Régions Arides at Medenine and with the "Faculté de Sciences Humaines et sociales" of Tunis and financed by the Sardinian Regional Government (R.L. 11 Aprile 1996, n° 19), our multidisciplinary Research Team has studied twenty-one geosites and geological landscapes in the region of Tozeur, with the purpose of constituting a network of geosites in these arid and semi-arid areas. Field work combined with remote sensing techniques have enabled to start preparing thematic maps of these geosites which, together with their description (genesis, evolution, state of conservation, proposals of valorisation, etc.) will be useful for obtaining financial aid for their protection and valorisation. The definition of morphostructural units landform analysis at a large/medium scale was performed by TeleGIS Laboratory, involved in these studies on southern Tunisia from 1997 in collaboration with the Institute des Régions Arides, applying remote sensing techniques on multi-spectral satellite images. During this project the interpretation keys for the image classification were created in the different steps of field observations and digital image processing. The radiometric and geometric responses were used for the discrimination of spectral units (lithological sequences) and textural units defined by photo-interpretation techniques (structural and landscape units like anticlines, fault-controlled valleys or forms like chevron, etc.). Many of the studied geomorphosites are represented by canyons (Gorges de Ben Nebhana, Sidi Bou Helal, Thelja, En Negueb, Chaabet Es Sfa, Ben Hamed, Midès, etc.) and waterfalls (Grande Cascade and Cascade de l'Oasis at Tameghza, Cascade de Chebìka and its geological-structural features). Others are related to aeolian and meteoric processes (Barchan dunes of El Ghadayer, morpho-sculpture of Ong El Jmel, Yardangs of El Ghadayer, Nebkha fields of Chamsa). The remaining geosites are an ancient lacustrine coastline testified by a lumachelle with Cardium in the Jehim oasis near Tozeur, the anticline of Brikis close to Tameghza, and an ancient phosphate mine at Chouabin (Jbel Chouabin close to Redeyef), a representative part of Chott el Djerid, the Delta of Oued Mellah and the alluvial cone of Oued Foum el Khanga and the ancient oasis (Corbeille) of Nefta. These sites and landscapes of geological and geomorphological interest represent the entire geological history of the Tozeur and the Chotts region fairly well. This history starts from Early Cretaceous, and the various sites narrate the sedimentary and tectonic events, the palaeo-environmental and palaeo-climate episodes, the birth, development and extinction of animal and plant species, the geomorphological processes and depositional events, explaining the present morphology, climate and landscape in a most interesting scientific and educational way. The linking of all these places of geological and geomorphologic interest in networks of Geosites along a thematic issue (the "Living Desert" network with Nebkha and Barchan dunes, Yardangs and Aeolian sculptures, the "Rocks and Water" network with waterfalls, mountains and canyons, the "Earth’s ...

Nella presente ricerca, eseguita nell’ambito di una tesi di dottorato dell’Università Mohammed V-Agdal di Rabat (D.ssa Amina Malaki), sono stati rilevati, studiati e catalogati in maniera sistematica quarantadue siti di interesse geologico e geomorfologico di particolare significato scientifico, didattico e turistico-culturale presenti all'interno o nell'intorno degli itinerari turistici del Medio Atlante di Ifrane-Azrou (Marocco). La scelta dei geositi e dei geomorfositi come obiettivo della ricerca è determinata non solo dalla carenza di ricerche specifiche sull’argomento ma anche dall'esistenza nel Marocco di caratteri e di fenomeni geologici e geomorfologici che lasciano presupporre la presenza di un consistente numero di tali beni naturali e culturali nello stesso tempo, i quali meritano di essere meglio conosciuti, tutelati e valorizzati. Le informazioni acquisite, relative a ciascun itinerario, sono state riassunte in una Carta geotematica tesa a consentire una sintesi efficace dei risultati conseguiti ed a fornire un quadro d'insieme della consistenza e della distribuzione territoriale di tali beni che costituiscono il patrimonio geologico del Medio Atlante ancora oggi poco conosciuto e sostanzialmente trascurato. La Carta contiene proposte per il rafforzamento degli itinerari turistici tradizionali legati ai beni culturali (es. città imperiali) con l'integrazione dei beni geografico-fisici (Geositi e Geomorfositi) e del paesaggio geologico.