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We present a geologic map of the Tekeze River basin that covers an area of ∼69,000 km2 of northern Ethiopia. The map synthesizes new data collected in two campaigns between March, 2012 and January, 2013 and compiled at a scale of 1:500,000 with published geologic surveys. The map focuses on the main geologic and tectonic features relevant to a modern interpretation of the geologic evolution of northern Ethiopia and as such, it represents an important synthesis for environmental and natural resource management.

An outlier consists of an area of younger rocks surrounded by older ones. Its formation is mainly related to the erosion of surrounding rocks which causes the interruption of the original continuity of the rocks. Because of its origin, an outlier is an important witness of the paleogeography of a region and, therefore, essential to understand its topographic and geological evolution. The Mekele Outlier (N Ethiopia) is characterized by poorly incised Mesozoic marine sediments and dolerites (∼2000 m in elevation), surrounded by strongly eroded Precambrian and Paleozoic rocks and Tertiary volcanic deposits in a context of a mantle supported topography. In the past, studies about the Mekele outlier focused mainly in the mere description of the stratigraphic and tectonic settings without taking into account the feedback between surface and deep processes in shaping such peculiar feature. In this study we present the geological and geomorphometric analyses of the Mekele Outlier taking into account the general topographic features (slope map, swath profiles, local relief), the river network and the principal tectonic lineaments of the outlier. The results trace the evolution of the study area as related not only to the mere erosion of the surrounding rocks but to a complex interaction between surface and deep processes where the lithology played a crucial role.

Despite the high geoheritage value of caves and karsts, northern Ethiopia’s largest cave at Zeyi (13.5586°N, 39.1454°E) in the Dogu’a Tembien district has received little attention so far. We have studied its geological, geomorphic, socio-cultural and historical dimensions in a holistic way. The basal member of the Antalo Limestone, in which the Zeyi cave is located, consists of grainstone and wackestone with subordinate marly interlayers. Over a length of 364 m, the oval-shaped gallery displays stalagmites, stalactites, five columns, dissolution holes (“bell-holes”) following joints, stalagmitic floors and other concretions or speleothems. In the absence of any dating of the cave, we contrasted its elevation above the current local base level with known average incision rates of the northern Ethiopian highlands to reconstruct its age, which was calculated as at least 2 to 4 million years. The palaeo-environmental information that is archived in the Zeyi cave sediment would hence cover the Pleistocene. The graves in the sediment at the bottom of the Zeyi cave further indicate that the place could be an ancient burial site, which gives scope for archaeological research. Zeyi boosts a unique combination of abiotic, biotic and cultural components: the nineteenth c. church under the overhanging cliff; the unique cave; the speleothems, cliffs and gorges; and the cave’s bat colony which has been genetically confirmed to be composed of three syntopically roosting species. Accounting for a good balance between cave research, community-based geotourism, geoconservation and biodiversity conservation, the Zeyi cave has strong credentials to become a top geotouristic site in northern Ethiopia. However, major work needs to be done, including granting access for women and organising community-based geotourism.

The Dogu’a Tembien Massif is located on the western margin of the Mekelle Outlier, a nearly circular mountainous area (8000 km2) with elevations ranging between 1200 and 2850 m (Fig. 2.1a).

The Antalo Supersequence, a marly-carbonatic marine succession of Jurassic age (Upper Oxfordian-Kimmeridgian; ca. 160–150 million years old), is widely outcropping in Dogu’a Tembien and the wider western part of the Mekelle Outlier (Chap. 2). Hence the landscape is characterised by the occurrence of various karst landforms including caves, speleothems, karren or lapiez, and a large number of relict tufa dams.

L’articolo presenta un quadro generale delle caratteristiche geomorfologiche della penisola calabrese in rapporto ai fattori geologici, climatici e antropici che ne hanno controllato e ne controllano tuttora la genesi e l’evoluzione. Un’attenzione particolare è stata rivolta agli effetti geomorfologici indotti nei tempi più recenti dall’impatto antropico sui sistemi idrografi ci e sulla costa. The article presents a general overview of the geomorphological features of the Calabrian peninsula in relation to the geological, climatic and anthropogenic factors that have controlled and still control their origin and evolution. Particular attention has been given to the environmental changes recently induced by human impact on the hydrographic systems and the coastline.

Tectonic processes and dynamic mantle flow impart a unique imprint on topography and geomorphic responses over time scales of 10 4 to 10 6 yr. First-order topographic features in a tectonically active landscape represent ways to quantitatively characterise the interaction between crustal tectonics, mantle dynamics, and geomorphology, providing a basis for modelling landscape evolution. We analysed the topographic features of the Romanian Carpathians, a mountain range characterised by two straight segments connected by a narrow curvature zone. The deformation started in the Late Jurassic and includes two collisional phases during the Cretaceous and Miocene. We examined the tectonic geomorphology of the Romanian Carpathians focusing on regional and local topographic setting, drainage pattern, and river long profiles. Our main database is composed of DEM-based topographic analysis, supplemented with field investigations in the Slanic River basin, located in the Carpathian curvature zone. The longitudinal profiles of rivers draining the southern Carpathians are close to the equilibrium shape, in agreement with the older emersion of the chain. The longitudinal profiles of the rivers draining the eastern and southeastern Carpathians are in a transient state of disequilibrium as a consequence of a more recent emersion of the chain and of the Pliocene–Pleistocene tectonic activity in the Bend Zone. Filtering the topography at different wavelengths, we observe a relative depression in correspondence with the Carpathian Bend, where mantle seismicity and a high-velocity zone in tomography data are located and commonly interpreted as related to an almost inactive and dying subduction zone. Contrastingly, the filtered topography presents a high in the Transylvanian basin, where tomography data show a low-velocity area, interpreted as upwelling of hot asthenospheric materials. We hypothesise that local mantle convection generates positive and negative dynamic topographies. In the Slanic River basin, the foredeep deposits (Middle Miocene–Upper Pliocene) are folded and tilted, suggesting active compression beginning in the Lower Pleistocene. During the Middle–Late Pleistocene and Holocene, four terrace orders developed by the interaction between regional uplift and climate changes. The Carpathian topography results from a diachronous uplift superimposed on crustal tectonics. This diachronous uplift influenced the chain topography, the shape of river longitudinal profiles, and the formation of strath terraces. Crustal tectonics dominated the hydrographic net organisation. In correspondence with the Carpathian Bend and the Transylvanian basin, mantle flow driven by slab pull produced negative and positive dynamic topographies.

Landslide hazard is one of the crucial environmental constraints for the development of Ethiopia, representing a limiting factor for urbanization and infrastructures. The high relief and the rugged topography induced by a strong Plio-Quaternary uplift, the occurrence of clayey horizons within the sedimentary sequences, the dense network of tectonic fractures and faults, the thick eluvial mantles on volcanic outcrops, and the thick colluvial–alluvial deposits at the foot of steep slopes are the predisposing factors for a large variety of mass movements. Heavy summer rainfall is the main triggering factor of most landslides, some of which undergo a step-like evolution with long-lasting quiescence intervals. First generation movements are commonly restricted to shallow phenomena, such as soil slips or mud flows in eluvial–colluvial material. Fast moving slope failures, such as rock slides, topplings and falls, are also triggered by earthquakes. To mitigate the landslide risk, any first priority measure should include adequate drainage of slopes in order to reduce water infiltration. On the other hand, appropriate site selection for buildings, transferring risky settlements, accurate geological control of works, and education campaigns are all strongly recommended.

In the present work we analyse one of the active normal faults affecting the central Apennines, i. e. the Mt. Morrone normal fault system. This tectonic structure, which comprises two parallel, NW-SE trending fault segments, is considered as potentially responsible for earthquakes of magnitude >= 6.5 and its last activation probably occurred during the second century AD. Structural observations performed along the fault planes have allowed to define the mainly normal kinematics of the tectonic structure, fitting an approximately N 20° trending extensional deformation. Geological and geomorphological investigations performed along the whole Mt. Morrone south-western slopes permitted us to identify the displacement of alluvial fans, attributed to Middle and Late Pleistocene by means of tephro-stratigraphic analyses and geomorphological correlations with dated lacustrine sequences, along the western fault branch. This allowed to evaluate in 0.4 ± 0.07 mm/year the slip rate of this segment. On the other hand, the lack of synchronous landforms and/or deposits that can be correlated across the eastern fault segment prevented the definition of the slip rate related to this fault branch. Nevertheless, basing on a critical review of the available literature dealing with normal fault systems evolution, we hypothesised a total slip rate of the fault system in the range of 0.4 ± 0.07 to 0.8 ± 0.09 mm/year. Moreover, basing on the length at surface of the Mt. Morrone fault system (i. e. 22-23 km) we estimated the maximum expected magnitude of an earthquake that might originate along this tectonic structure in the order of 6.6-6.7. © 2009 Springer-Verlag.

Please click here to download the map associated with this article. This paper describes a geomorphological map representing a sector of the Ionian coastal belt, located in north-eastern Calabria, between the catchments of the Trionto and Colognati Rivers. The landforms have been distinguished according to their origin into: a) structural and tectonic-controlled landforms; b) gravity-induced landforms; c) landforms formed by running water; d) coastal and transitional landforms; e) anthropic landforms, using as support a simplified topographic map on scale 1:20,000. The geomorphological map provides information about the long-term evolution of the landscape and identifies the geomorphic processes presently active. Therefore, the map could be used in developing land management and planning guidelines.

Planation surfaces are an old-fashioned topic in geomorphology, but they are nevertheless important where they make up much of the landscape. Northern Ethiopia is largely a stepped topography, caused by differential erosion. Exhumation of old planation surfaces that were preserved under sedimentary or volcanic cover is an important process in landscape evolution. The oldest planation surface is of early Palaeozoic age (PS1); the second is Late Triassic (PS2); and the third is of Early Cretaceous age (PS3). The Oligocene Trap Volcanics buried a surface (PS4) of early Tertiary age, which is now widely exposed by erosion as a surface that, where flat enough, is an exhumed planation surface. The surfaces do not relate to the supposed Africa-wide pediplain sequence of King [King, L.C., 1975. Planation surfaces upon highlands. Z. Geomorph. NF 20 (2), 133–148.], either in mode of formation and age. Although the region is tropical, there is scarce evidence of deep weathering and few indications that the surfaces could be regarded as etchplains. These surfaces indicate that eastern Africa underwent long episodes of tectonic quiescence during which erosion processes were able to planate the surface at altitudes not too far from sea level. Only after the onset of rifting processes, uplift became active and transformed a vast lowland plain into the present Ethiopian highlands, largely exceeding 2500 m a.s.l. Some hypotheses and speculations on the genesis of these surfaces are considered here.

This paper presents an overview of the potentially dangerous geological–geomorphological processes that characterize the territory of Ethiopia. Due to the active crustal mobility causing the ongoing rifting between the Arabian and African plates, this country is particularly prone to high magnitude earthquakes and volcanic eruptions. Moreover, the climate, characterized by long-lasting and intense precipitation during the rainy seasons, and the recurrent earthquake shocks are the triggering factors of a variety of landslides that are particularly favoured by the rugged topography, marked by deep valleys and high steep slopes. All these processes may induce different levels of risk in relation to the different hazards and vulnerabilities, especially after the recent development and planning of road networks, dams, reservoirs, and the establishment of new urban settlements in previously uninhabited areas. Finally, an overview of the measures taken by the Ethiopian authorities so far to mitigate geological hazards is presented along with some proposals for future mitigation initiatives.

SUMMARY In this paper we show that the processes that have shaped the Quaternary surface development of the Apennines in central Italy are all consequences of a single subcrustal process, the upwelling of the mantle. The relationship between gravity and topography shows that mantle convection is responsible for a long-wavelength (150‐200 km) topographic bulge over the central Apennines, and stratigraphic evidence suggests this bulge developed in the Quaternary. Active normal faulting is localized at the crest of this bulge and produces internally-draining fault-bounded basins. These basins have been progressively captured by the aggressive headward erosion of major streams that cut down to the sea on the flanks of the regional bulge. The only surviving closed basins are those on the Apennine watershed most distant from the marine base level, where continued normal faulting is still able to provide local subsidence that defeats their capture by the regional drainage network. Understanding the competition between regional capture and local, fault-related subsidence of intermontane basins is crucial for recognizing potentially hazardous active faults in the landscape and also for interpreting the sediment supply to adjacent offshore regions. Central Italy provides a good modern analogue for processes that are probably common in the geological record, particularly on rifted margins and intracontinental rifts, but may not have been fully appreciated.

This paper discusses the Holocene evolution of two sites in the Central Italian Alps, the Foscagno Valley and the Stelvio–Livrio area, in terms of the interaction between permafrost distribution and glacial history. The applicability of phytosociological vegetation survey to investigate recent glacial evolution where geomorphological evidence is poor or totally absent is also illustrated. Bottom temperature of snow measurements and detailed geomorphologic survey and air-photo interpretation were carried out in the Stelvio–Livrio area. Boreholes were drilled in each site, one (24 m deep) in the Foscagno rock glacier (2510 m ASL), the second (100.3 m deep) in dolostone-limestone bedrock at the Stelvio Pass (3000 m ASL). The latter borehole is a component of the PACE European Permafrost Monitoring Network. In Foscagno Valley, the formation of permafrost during a cold and dry phase of the Holocene allowed the preservation of an ice body which otherwise would have disappeared. More recently, a Little Ice Age glacier advance, whose exact location and extension were defined by means of the analysis of vegetal associations, induced some degradation in the permafrost. In the Stelvio–Livrio area, a cold-based glacier apparently had much less influence on the local permafrost evolution and thermal regime. Copyright © 2001 John Wiley & Sons, Ltd. RESUME L'evolution holocene de deux sites des Alpes centrales italiennes, la vallee de Foscagno et la region de Stelvio-Livrio, est discutee pour contribuer a la comprehension des relations entre la distribution du pergelisol et l'histoire glaciaire. Un autre but de l'etude etait de verifier la possibilite d'utiliser des releves phytosociologiques pour comprendre l 'evolution recente glaciaire de zones ou des evidences geomorphologiques sont maigres ou totalement absentes et de mieux comprendre ainsi la distribution du pergelisol. Des mesures BTS, des leves geomorphologiques detailles et des interpretations de photos aeriennes de la zone Stelvio-Livrio ont ete realises. Enfin, deux sondages ont ete implantes : l'un (24 m de profondeur) dans le glacier rocheux de Foscagno (2510 m) et l'autre dans le substratum rocheux (100.3 m de profondeur) du Col du Stelvio (3000 m). Ce dernier sondage fait partie du reseau europeen PACE de surveillance du pergelisol. Des leves phytosociologiques ont ete realises dans les deux zones. Dans la vallee de Foscagno, la formation du pergelisol pendant une phase froide et aride de l'Holocene a permis la conservation d'un corps de glace qui, autrement, aurait disparu. Plus recemment, une avancee glaciaire pendant le Petit Age Glaciaire (dont la localisation et l'exacte extension ont ete reconnues par les etudes phytosociologiques) a provoque la degradation du pergelisol. Dans la zone de Stelvio-Livrio, un glacier a base froide a apparemment beaucoup moins influence la distribution du pergelisol et son regime thermique. Copyright © 2001 John Wiley & Sons, Ltd.

This paper outlines the environmental history of the Tigrean Plateau (northern Ethiopia) during the Holocene, based on the available geomorphological, palynological, archaeological, and historical evidence. At present, it seems that (1) the plateau experienced a more humid climate with a denser vegetation cover during the Early Holocene; (2) Soil erosion due to clearing vegetation began in the Middle Holocene; (3) agricultural activity was intensified in the Late Holocene, as a consequence of the rise of a state; (4) demographic pressure increased from the early first millennium BC to the mid–first millennium AD, causing soil erosion; (5) environmental degradation and demographic decline occurred in the late first millennium AD; (6) the vegetation cover was regenerated in the early second millennium AD; and (7) progressive vegetation clearance started again in the second half of the second millennium AD. Cet article trace l'histoire ambiante du Plateau Tigreen dans l'Holocene en utilisant les donnees geomorphologiques, palynologiques, archeologiques et historiques. Il semble que (1) dans l'Holocene ancien le plateau etait caracterise par une phase humide avec une dense vegetation; (2) l'erosion causee par l'abbattage de la vegetation commen¸a dans l'Holocene moyen; (3) l'activite agricole s'intensifia a la fin de l'Holocene, par consequence de l'essor d'un etat; (4) la pression demographique augmenta de plus en plus du debut du premier millenaire av. J.-Ch. a la moitie du premier millenaire ap. J.-Ch.; (5) la degradation ambiante et la diminution demographique se verifierent a la fin du premier millenaire ap. J.-Ch.; (6) une regeneration de la vegetation se verifia au debut du seconde millenaire ap. J.-Ch.; et (7) l'abbatage de la vegetation recommen¸a dans la seconde moitie du seconde millenaire ap. J.-Ch.

This paper presents a geomorphologic–stratigraphic analysis of a travertine dammed lacustrine–swampy sedimentary sequence, composed of clay, peaty layers and phytoclastic travertine sands, deeply incised by the Mai Maikden river, on the Highlands of Tigray (Northern Ethiopia). Radiocarbon datings of peaty deposits allow us to establish that the travertine dams have developed at least between 7310±90 yr B.P. and 5160±80 yr B.P. In the upper part of the sequence, palaeochannels filled with travertine and limestone coarse gravels and blocks, indicate the activation of concentrated erosion on the surrounding slopes. Later, both the travertine dam and the lacustrine–swampy deposits were buried by alluvial and colluvial sediments, still mixed with large amounts of organic matter, testifying to generalized slope erosion processes. The end of travertine deposition may be connected with a progressive reduction of vegetation cover and the subsequent decrease of CO2 in groundwater. The occurrence of the latter phenomena may be related to the onset of drier climatic conditions even though the finding of a large prehistoric settlement in the area, also indicates some influence of human impact.

Active faulting is one of the main factors that induce deep-seated gravitational slope deformations (DGSDs). In this study, we investigate the relationships between the tectonic activity of the NW-SE normal fault system along Mt. Morrone, central Apennines, Italy, and the evolution of the associated sackung-type DGSD. The fault system is considered to be the source of M 6.5-7 earthquakes. Our investigations have revealed that the DGSD began to affect the Mt. Morrone SW slope after the Early Pleistocene. This was due to the progressive slope instability arising from the onset of the younger western fault, with the older eastern fault acting as the preferred sliding zone. Paleoseismological investigations based on the excavation of slope deposits across gravitational troughs revealed that the DGSD was also responsible for the displacement of Late Pleistocene-Holocene sediments accumulated in the sackung troughs. Moreover, we observed that the investigated DGSD can evolve into large-scale rock slides. Therefore, as well as active normal faulting, the DGSD should be considered as the source of a further geological hazard. Overall, our approach can be successfully applied to other contexts where active normal faults control the inception and evolution of a DGSD. © 2013 Elsevier B.V.

After a review of some analytical and conceptual models of slope evolution with the intervention of mass movements, a proposal is made of a series of indicators for the quantitative description of landscape evolution in relation to mass movements. The ratio between landslide mobilisation rate and downwearing rate is proposed as a quantitative measure of the significance of mass movements in landscape evolution. A subdivision of European regions with respect to their susceptibility to landsliding as a process of landscape evolution is proposed. The role of landsliding for the evolution of landscape in some regions is described. The data presented show that landsliding may in some cases be the main contributor to landscape change.

This paper presents the results of a geo-environmental study carried out in the urban area of Dessie town, one of main urban centres of Ethiopia with 200,000 inhabitants. In this area, landslides heavily interact with a disorderly expanding human settlement, inducing high risk conditions for human lives, buildings, infrastructures and economic activities. Based on a detailed geological and geomorphological field survey and mapping, a GIS-based analysis of landslide susceptibility has been applied to the Dessie basin, one of the “hanging” tectonic depressions located along the western Afar margin. Landslide hazard and risk maps were successively produced for the central sector of Dessie town. The landslide risk map and the related report will constitute the starting point for a possible plan of risk mitigation in the urban area of Dessie.

Stratified slope-waste deposits are widespread in central Italy, even at elevations close to the present coastline. They are evidence of the cold climatic conditions which affected the area during the cold stages of the Upper Pleistocene. Their occurrence was strongly influenced by bedrock lithology (they are common on slopes composed of micritic and marly limestone). Detailed morphostratigraphic analysis and 14C dating of alluvial and inter-fingered slope-waste deposits in a mountain area of the Umbria-Marche Apennine (Upper Esino River basin) allows an outline of the chronological sequence of debris depositional phases during the Late Pleistocene. A few dates were also obtained from the Ponte di Crispiero sequence (in the contiguous Potenza River basin), which may be considered as a type section for the Late Pleistocene of Central Italy, Adriatic side. The stratified slope-waste deposits were deposited after 50,000 to 60,000 years BP, in the Stadials of the Middle and Upper Pleniglacial. During the Interstadials, most of the slopes of the basin were colonized by steppe vegetation and the production of stratified debris was probaby restricted to the highest elevations. Increased rates of debris deposition occurred during the Upper Pleniglacial. Des depǒts stratifies de pente sont nombreux en Italie centrale. Měme a des altitudes proches du niveau actuel de la mer. Ils constituent des preuves des conditions climatiques froides qui ont regne sur la region pendant le Pleistocene superieur. Leur existence est fortement influenceee par la lithologie (ils sont communs sur des pentes developees sur des calcaires micritiques et marneux). Un analyse morphostratigraphique detaillee et des datations 14C des depǒts alluviaux et de ruissellement interstratifies dans une region montagneuse des Apennins de l'Ombrie-Marche (bassin superieur de la riviere Esino) permettent d'etablir les grandes lignes de la sequence chronologique des phases de depǒts de la fin du Pleistocene. Quelques dates ont ete obtenues egalement dans la sequence de Ponte di Crispiero (dans le bassin contigu de la riviere Potenza), section qui peut ětre consideree comme typique de la fin du Pleistocene de l'Italie centrale du cǒte de l'Adriatique. Les depǒts de pente stratifies ont ete deposes apres 50-60.000 ans B.P., au cours des stades du Pleniglaciaire moyen et superieur. Pendant les interstades, la majorite des pentes du bassin

Deep-seated gravitational slope deformations and their relationships with tectonic deformation of rocks is considered, to examine the viewpoint of Tectonics as a causative factor in slope deformation. First, a distinction is made between the different types of deep-seated gravitational slope deformation. Then, the geomorphological and structural effects of the different macrostructural deformations induced by tectonics, on the scale of the whole deforming ridge is briefly discussed. Finally, some case studies that represent either verified or possible cases of gravity deformation in response to tectonic activity are used as illustration.

This chapter deals with types, purposes, contents and perspectives of geomorphological mapping, from the widely applied, ‘traditional’ symbol-based maps to the modern geographical information system (GIS)-based, object-oriented geomorphological mapping models, capable of providing reliable multiscale cartographic support to environmental analysis and land planning projects. In the last decades, the availability of new tools such as satellite imagery, global positioning systems, digital elevation models and GIS has induced a new, more effective approach in the acquisition, storage and display of geomorphological features. By this approach, geomorphologists can produce geomorphological models, consisting of land surface ‘objects’, organised into hierarchically arranged classes with spatially and temporally variable properties and geometric relationships. Unlike ‘traditional’ maps, object-oriented models can provide a full geometric description of landforms and near-surface deposits. Moreover, generalisation/decomposition procedures allow the translation of geomorphological objects from larger to smaller scales and vice versa. A case study of a GIS-based, object-oriented geomorphological model, in which ‘traditional’ symbol-oriented mapping is associated with grid-based/object-based analysis, is provided by the Salerno University (Italy) GeoMorphological Information System (GmIS). Some significant examples of traditional geomorphological maps and multiscale object-oriented mapping models produced at the Salerno University are presented in the annexes.

The morphotectonic framework of the Central Apennines is given by faulted blocks bounded by normal faults, mostly trending NW-SE, NNW-SSE and NE-SW, which cut previous compressive structures. Such a structural setting is consistent with the lbcal mechanisms of the earthquakes which often occur in this area. In this paper, three lithologically different normal fault-generated mountain fronts are analysed in order to assess the relations between their geomorphic features and active tectonics. They border the Norcia depression (Sibillini Mts, Umbria), the Amatrice{ampotosto plateau (Laga Mts, Lazio) and the Fucino basin (Marsica Mts, Abruzzi). The Norcia depression is bounded by a N20"W trending normal fault to the east and by a parallel antithetic fault to the west. The main fault has a 1000 m throw and gives rise to a wide fault escarpment, characterized by: (l) sharp slope breaks due to low angle gravity faults; (2) important paleolandslides; and (3) several fault scarplets on the piedmont belt affecting Quaternary deposits. The Amatrice{ampotosto plateau is delimited by the western slope of Mt Gorzano which runs along a N20'W trending normal fault having a 1500m throw. Minor parallel faults dislocate Quaternary landforms. Large-scale massmovements also occur here. , "e The Fucino basin was struck by th-e 1915 Avezzano earthquake 0 : XI MCS) which produced extensive surface faulting along two parallel NW trending normal fault escarpments on the eastern border of the basin. There is paleoseismrc evidence including buried gravity graben in Late Glacial gravels and tectonic dip-slip striations on Holocene calcitic crusts covering bedrock normal fault planes. These data suggest that active extensional tectonics plays a major role in the slope morphogenesis of the Central Apennines and they indicate the importance of geomorphic analysis in seismic zonation of this area.

The relationship between mountain permafrost and climate is still relatively unknown. The implications of zonation (latitude, continentality), the various climatic parameters (MAAT; freezing and thawing indices; basal snow temperature, BTS; solar radiation; and surface heat balance) and climate change are outlined for mountain permafrost. Some research priorities are suggested.

In this paper we present the results of an integrated geomorphological, pedological and stratigraphical study carried out along the Ionian coast of northern Calabria (southern Italy). This area is characterised by the occurrence of five orders of alluvial terraces that are striking features of the landscape, where large and steep catchments debouch from the mountain front to the hilly coastal belt. Field investigations indicate that the deposits of all five terraces are suggestive of shallow gravel-bed braided streams. On the basis of the age of the Pleistocene substratum and morphostratigraphic correlation with marine terraces cropping out in the nearby areas, each order has been associated to specific marine oxygen isotope stages. Consequently, we focused on the interplay of allocyclic factors influencing stream aggradation/degradation. Soil features and other climatic proxies suggest that climate didn't play an important role with respect to tectonic and base-level changes in controlling fluvial dynamics. In particular, we recognised that during the middle Pleistocene the study area experienced a period of subaerial landscape modelling, as suggested by the thick and complex alluvial sequence of the highest terrace (T1). The onset of regional uplift marks a change in the geomorphic scenario, with tectonic and eustatically driven changes in base-level working together in causing switches in fluvial aggradational/erosional phases (T2–T5 terraces). Because of the uplift, river dissection occurred during phases of sea level fall, whereas aggradation phases occurred during periods of climate amelioration (sea level rise) just before highstands were attained. As a consequence, the stepped terraces in the study area reflect the interplay between tectonics (uplift) and sea level changes, in which terraces define episodes of relative sea level fall during the late Quaternary.

This paper illustrates a geographic information system (GIS) supported methodology for the assessment of landslide susceptibility. The methodology involves four operational steps: survey, site analysis, macro-area analysis and susceptibility analysis. The Survey includes the production (or acquisition) of a large-scale litho-technical map, a large-scale geomorphological map, a detailed inventory of past and present landslide events, and a high resolution DTM (Digital Terrain Model. Site analysis leads to the definition of discriminating parameters (commonly, lithological and morphometric conditions necessary but not sufficient to trigger a landslide of a given type) and predisposing factors (conditions that worsen slope stability but are not sufficient to trigger a landslide of a given type in the absence of discriminating parameters). The different predisposing factors are subdivided into classes, whose intervals are established by descriptive, statistical analysis of landslide inventory data. A numerical index, based on the frequency of landslide occurrence, quantifies the contribution of each class to slope instability. Macro-area analysis includes the generation of Litho-Morphometric Units (LMU) by overlaying discriminating parameters, manual drawing of LMU envelopes (macro-areas), generation of predisposing factor maps from the spatial distribution of predisposing factors, and heuristic weighting of predisposing factor indices. Susceptibility analysis includes the generation of Homogeneous Territorial Units (HTU) by overlaying macro-areas and predisposing factor maps, and the application of a susceptibility function to the different HTU. The resulting values are normalized before the generation of the landslide susceptibility maps. The methodology has been applied to the Fiumicino River catchment, located in the western side of Latium Apennine (Central Italy) between 200 and 1300 m a.s.l. and developed on Late Miocene calcarenites, sandstones with clay intercalations, and marls. The resulting landslide susceptibility maps will be employed in environmental management. They also represent the preliminary step for the assessment of landslide hazard and risk.

Please click here to download the map associated with this article. The geomorphological map described below covers an area of about 100 km, located on the southeastern slope of Mt. Amba Aradam (northern Ethiopia). It has been produced within the Ethio-Italian Cooperation Programme, in order to understand the recent evolution and present-day trends of the area as a basic tool for land reclamation/rehabilitation projects. The survey was carried out in three successive work campaigns (February 1995, February-March 1996 and December 2002) following the Italian Environmental Agency guidelines. The main geomorphological processes responsible for present-day landscape modelling in the investigation area, are gravity-driven mass movements and slope erosion due to running water. They strongly affect human activities, especially in terms of agriculture and infrastructure management. This map may therefore represent a useful document for land management as well as the initial step for the assessment of geo...

Detailed geological-geomorphological investigations, carried out in the Ionian coastal belt between the Trionto River and the Colognati River, allowed us to set up a tectonic-sedimentary model of the northern flank of the Sila Massif during Pliocene-Pleistocene times. The study area is characterised by a distinct step-like topography displaying a well-preserved flight of coastal plain (alluvial/marine) terraces, arranged in five altimetric orders (T1 to T5). The deposition of sandy-clayey marine sediments of Middle Pliocene age ( CTSL Unit ) and beach sandstones grading upward to gray silty clays, referred to the Emilian-Sicilian ( Bisciglia Unit ) on the basis of micropaleontological analysis, has been related to a phase of subsidence, likely induced by the activity of E-W trending extensional faults. The Bisciglia Unit grades westward into conglomerates, sandstones and silty-clay sediments forming part of juxtaposed and superimposed deltaic (and subordinate alluvial/beach) deposits. A phase of subaerial landscape modelling, starting from the Middle Pleistocene, marks the end of subsidence and the onset of a rapid uplift which, interacting with eustatic sea-level changes, gave rise to the five orders of terraces. The uplift rate of the whole area, inferred by correlating the terrace surfaces with the paleoclimatic curve proposed by Bintanja et alii (2005), is 0.65 ± 0.1 mm yr −1 . However, the contemporaneous occurrence of extensional fault activity in the area induced variations in the uplift rates, which actually range between 0.52 and 0.88 mm yr _1 in relation to the distance from the fault trace. These data highlight the competing role of fault activity and regional uplift in controlling vertical movements and surface topography at the local scale.

This paper presents a detailed geomorphological overview of the landforms and processes characterizing the Dessie basin, a small graben located on the western Afar Margin (Ethiopia), which is a physiographic province characterized by small, closed basins and mountain ranges produced by regional extension. Large-scale geomorphological survey and mapping of the basin allowed to point out the noteworthy morphodynamic role of the present-day slope processes, including numerous landslides of different typology and size. These processes heavily interact with the built-up area of Dessie town, one of the most important cities of Ethiopia with ca. 200,000 inhabitants, which occupies a large part of the basin floor. The potential incidence of landslides of different typology in the basin and their possible impact on the urban settlement are put in relation with the distribution of the different landform units which make up the basin surface.

Debate in neotectonics mainly hinges on how far back in time the prefix ‘neo’ should be taken. The term ‘neotectonics’ means, in a first approximation, geologically young, recent or living (active) crustal structures and processes. Some of the many definitions (Angelier 1976; Mercier 1976; Beloussov 1978; Hancock and Williams 1986; Vita-Finzi 1986; Winslow 1986) focus neotectonic studies only on active deformation (late Quaternary–Present) and accept neotectonics as more or less synonymous to active tectonics, while others trace the neotectonic period mainly from the Middle Miocene. It is very difficult to identify a standard time period for defining the beginning of neotectonics, but the present-day opinion is that it depends on the individual characteristics of each geological environment. According to Fourniguet (1987), no time limit is fixed and the field of investigation extends from the present as far back into the past as necessary to understand present or active deformation. The INQUA (International Union for Quaternary Research) Tectonic Commission has accepted the definition of Mörner (1978): ‘Neotectonics is defined as any earth movements or deformations of the geodetic reference level, their mechanisms, their geological origin, their implications for various practical purposes and their future extrapolations.’ Pavlides (1989) proposed a definition along the following lines: ‘Neotectonics is the study of young tectonic events (deformation of upper crust), which have occurred or are still occurring in a given region after its final orogeny (at least for recent orogenies) or more precisely after its last significant reorganization.’ When western Europe is considered, a major change in boundary conditions occurred in the Upper Miocene (7 Ma) when the motion of Africa became directed to the north-west (Dewey et al. 1989). Geological, seismological, and geodetic data in the Mediterranean region and in continental Europe show that the relative motion of Africa and Europe is still in this direction. For this reason we think that for the neotectonics of western Europe one cannot go far back in time beyond the Upper Miocene. The study of the state of stress of the lithosphere around the world has recently been attempted within the World Stress Map Project of the International Lithosphere Programme (Zoback 1992).

The records of 92 pluviometric stations located in the Trentino Province (Italian Eastern Alps) were analyzed in order to find significant features in their spatial and temporal distribution. Differentiation of climatic regimes was detected, as well as the influence of many topographic-geographic parameters. Analyses of the data from the 20 stations with the best continuity of records indicate some periodic trends, with a major influence of those having a wavelength of ca. 26.7, 36.9 and 13.5 years. Also non strictly periodic Mediterranean oscillations influences the precipitation in the study area.