Recognition of landslides in lunar impact craters

Landslides have been observed on several planets and minor bodies of the solar System, including the Moon. Notwithstanding different types of slope failures have been studied on the Moon, a detailed lunar landslide inventory is still pending. Undoubtedly, such will be in a benefit for future geological and morphological studies, as well in hazard, risk and suscept- ibility assessments. A preliminary survey of lunar landslides in impact craters has been done using visual inspection on images and digital elevation model (DEM) (Brunetti et al. 2015) but this method suffers from subjective interpretation. A new methodology based on polynomial interpolation of crater cross-sections extracted from global lunar DEMs is presented in this paper. Because of their properties, Chebyshev polynomials were already exploited for para- metric classification of different crater morphologies (Mahanti et al., 2014). Here, their use has been extended to the discrimination of slumps in simple impact craters. Two criteria for recognition have provided the best results: one based on fixing an empirical absolute thresholding and a second based on statistical adaptive thresholding. The application of both criteria to a data set made up of 204 lunar craters’ cross-sections has demonstrated that the former criterion provides the best recognition

Su Fossu de Cannas Cave (Sadali, central-eastern Sardinia, Italy): the earliest deposit holding Pleistocene megacerine remains in Sardinia

Recentment s'han descobert diverses restes de cèrvids als sediments arenosos, vermells i fortament cimentats que omplen la cavitat superior de la Cava Su Fossu de Cannas (Sadali, Sardenya centre-oriental), tallada a les calcàries del Mesozoic de Barbagia di Seulo. Es varen trobar les restes a la part de dalt d'una cova horitzontal, estreta. L'origen d'aquest passadís es pot deure a una fase erosiva antiga (Pleistocè Mitjà?) que va afectar els sediments que primàriament omplien la cova, com s'evidencia per l'erosió del conglomerat superior i la deposició posterior de sediments vermellosos lleugerament cimentats. Els espècimens analitzats fins ara mostren afinitats morfològiques estretes amb el megacerí endèmic de Sardenya "Praemegaceros" cazioti (Depéret, 1897). No obstant això, el cèrvid de Sadali es diferencia del darrer per la seva mida més gran, que supera l'espectre de variabilitat calculat per a l'espècie endèmica, i en alguns trets morfològics (tal com el corpu.s rnandibulae fondo i corbat), aixi com per presentar unes dents proporcionalment més petites í, sobretot, per un metacarpià més gràcil. Els trets peculiars dels espècimens de Sadali suggereixen la seva pertinença a una nova espècie. No obstant això, de moment ens estimem més no batejar-la i anomenar el cèrvid de Sad ali "Praemegaceros" n. sp., a l'espera de noves dades que permetin afinar la seva diagnosi. El cèrvid de Su Fossu de Cannas es pot considerar com el representant més primitiu del gènere "Praemegaceros" a Sardenya i l'ancestre de "Praemegaceros" cazioti.Several cervid remains have recently been discovered in the sandy, red-coloured and strongly cemented sediment filling the uppermost cavity of the Su Fossu de Cannas Cave (Sadali, central-eastern Sardinia), cut into the Mesozoic limestone in the Barbagia ofSeulo. The remains were found on the ceiling ofa narrow, horizontal underground cave. The origin of this passage may be due to an ancient erosional phase (Middle Pleistocene?), which affected the sediments formerly filling up the cave, as evidenced by the erosion of the uppermost conglomerate and by the further deposition of reddish, slightly cemented sediments. The specimens analysed thus far show close morphological affinities with the endemic Sardinian megacerine "Praemegaceros" cazioti (Depéret, 1897). However, the Sadali cervid differs from the latter in its larger size, exceeding the range of variability calculated for the endemic species, and in some morphological features (such as the depth and curved corpu.s mandibulaei, as well as in its proportionally smaller teeth and, notably, its elongated, slender metacarpal. The peculiar features of the Sadalí specimens suggest its attribution to a new species. Nevertheless, for the moment, we prefer to name the Sadali cervid "Praemegaceros" n. sp., awaiting new data to present the diagnosis. The Su Fossu de Cannas cervid can be regarded as the most primitive representative of the genus "Praemegaceros" in Sardinia and the ancestor of the endemic species "Praemegaceros" cazioti

On the Use of Tri-Stereo Pleiades Images for the Morphometric Measurement of Dolines in the Basaltic Plateau of Azrou (Middle Atlas, Morocco)

Hundreds of large and deep collapse dolines dot the surface of the Quaternary basaltic plateau of Azrou, in the Middle Atlas of Morocco. In the absence of detailed topographic maps, the morphometric study of such a large number of features requires the use of remote sensing techniques. We present the processing, extraction, and validation of depth measurements of 89 dolines using tri-stereo Pleiades images acquired in 2018–2019 (the European Space Agency (ESA) © CNES 2018, distributed by Airbus DS). Satellite image-derived DEMs were field-verified using traditional mapping techniques, which showed a very good agreement between field and remote sensing measures. The high resolution of these tri-stereo images allowed to automatically generate accurate morphometric datasets not only regarding the planimetric parameters of the dolines (diameters, contours, orientation of long axes), but also for what concerns their depth and altimetric profiles. Our study demonstrates the potential of using these types of images on rugged morphologies and for the measurement of steep depressions, where traditional remote sensing techniques may be hindered by shadow zones and blind portions. Tri-stereo images might also be suitable for the measurement of deep and steep depressions (skylights and collapses) on Martian and Lunar lava flows, suitable targets for future planetary cave exploration

First steps towards a landslide inventory map of the Central Karakoram National Park

The northeastern part of Pakistan is known to be a region of extremes, where the highest reliefs and the longest glaciers of the world may be found. In this environment, through the multidisciplinary Social, Economic and Environmental Development (SEED) Project the knowledge of the sustainable exploitation possibilities of the Central Karakoram National Park area (CKNP) will be improved. One of this project's objectives is the analysis of the geological hazards giving as output a landslide inventory and a susceptibility map, utilizable as functional tools for a future sustainable territorial planning. The Bagrot Valley, chosen as test site, was partially field surveyed and part of the landslide-prone areas preliminarily identified through DEM analysis, GIS techniques and Analytical Hierarchy Process (AHP) methodology, were later validated on the field. ASTER DEM was used as the basis of morphometric analysis

ANALYSIS OF SPATIO-TEMPORAL DYNAMICS OF AEOLIAN PROCESSES IN ARID AND SEMI-ARID AREAS USING REMOTE SENSING

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Studio dei fenomeni di dissesto geologico sulla superficie lunare a partire dai dati telerilevati dai satelliti Chang’E 1 e 2

The exploration of the Moon has become an important goal for several countries in order to set up foundations for future exploration of mineral resources. In the framework of the cooperation project “Moon Mapping” between Italy and P.R. China, a working group has been established to study landslides inside impact craters. So far, WAC (Wide Angle Camera) images and DEM (Digital Elevation Model) maps from LROC (NASA) at 100 m/pixel have been used to visually recognize some landslides in impact craters. Further steps include: (i) the classification of impact craters; (ii) the identification for each crater type of a theoretical shape; (iii) the automatic identification of the landslide through the analysis of deviations from the theoretical shape; (iv) the measurement of the landslide deposit volume; (v) the analysis of relationships between landslides and characteristics of the hosting craters and of the surrounding terrain (topographic slope, geology, etc); (vi) the comparison of multispectral data with available spectral libraries to map geological features on the Moon surfaces

FLOWERED-GeoDBapp: applicazione per mobile basata sui crowd- generating data

Questo studio è parte del progetto H2020 FLOWERED (de-FLuoridation technologies for imprOving quality of WatEr and agRo-animal products along the East African Rift Valley in the context of aDaptation to climate change), coordinato dal Dipartimento di Scienze chimiche e geologiche dell’Università di cagliari, che vede la partecipazione di 14 partner di cui 5 provenienti dalla regione della Rift Valley africana (Etiopia, Kenya e Tanzania). Obiettivo generale del progetto iniziato nel 2016 e di durata triennale, è lo studio nelle tre aree test africane di un sistema di de - fluorizzazione dell’acqua contaminata per cause naturali basato sia su tecnologie adattabili al contesto sociale che su un attento sistema di gestione della risorsa acqua. Pertanto uno degli obiettivi del progetto è il coinvolgimento delle comunità locali nel processo sia di acquisizione delle conoscenze che di proposta dei sistemi di intervento. In questo ambito è stato proposto lo sviluppo di una piattaforma di condivisione di dati ambientali e socio- economici basata sula raccolta di dati da parte dei tecnici locali. La disponibilità e diffusione di tecnologie di accesso alla rete internet anche in territori remoti e con particolari condizioni sociali può consentire pertanto l’utilizzo di strumenti di gestione di dati geografici attraverso esperienze di PPGIS (Public Participation Geographic Information System) e VGI (Voluntary Geographic Information). In questo ambito si inserisce l’applicazione FLOWERED-GeoDBapp, che attraverso un processo di crowd-generating data intende proporre un sistema di passaggio land cover-land use attraverso il popolamento di un GEO DB basato su una mappa di land cover da classificazione di dati da satellite ad alta risoluzione con dati specifici sull’uso del territorio inseriti localmente. Sarà pertanto proposta una legenda di land use basata sulla raccolta di dati non solo di natura ambientale ma anche sociale, culturale ed economica, utilizzando le conoscenze locali e rendendo poi disponibili ai tecnici locali e agli amministratori le informazioni necessarie alla gestione delle risorse e in particolare dell’acqua