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Abstract: The Plan di Modzon is a mountain area (2300 m) located in the Verrogne Valley, NW of Aosta (Western Alps). It occurs along the contact between the Middle Penninic (micaschist and gneiss from the Gran San Bernardo Nappe) and the overlying upper units of the Piedmont Zone (carbonate calcschist alternating with marble). This area, largely shaped by Pleistocene glaciers, was involved in a wide deep-seated gravitational slope deformation (Pointe Leysser DSGSD) on the western extension of the Becca France doubled ridges. Several ridges that were affected by glacial erosion, discontinuously covered by glacial sediments, are present throughout the area. Extremely fractured rocks and various gravitational forms (minor scarps and trenches) mark the DSGSD. Several archaeological sites (MF1–MF9) have recently been found between 2242 and 2292 m asl. They have revealed artifacts of rock crystal (hyaline quartz) referred to the Sauveterrian stage of the Mesolithic. An ensemble of other archaeological evidence is referred to the Copper Age. The investigation in progress specifically concerns the systematic excavation of sites MF1 and MF3. Some concomitant morphological factors have created very favorable conditions for prehistoric settlements in the Plan di Modzon area, including the exceptionally wide valley floor directly perched on the main Dora Baltea Valley, in consequence of the Verrogne Glacier diversion promoted by the P. Leysser DSGSD. Easy and direct accessibility to this area is provided by the gently-dipping slope of the Dora Baltea Valley affected by the DSGSD. The ridged and grooved morphology as the result of the glacial and gravitational interaction, offered wide surfaces free from geological hazards (debris flow and avalanche processes). The DSGSD is, therefore, one of the primary causes of the archaeological settlement of this area, contributing to create a morphology adapted to prehistoric settlements. [Copyright &y& Elsevier]

Abstract: The Ivrea amphitheatre (IA) in NW Italy has been studied since 1850, on pedostratigraphic and morphological bases. Three stratigraphic groups of glacial sediments were distinguished. Newly recognized stratigraphic boundaries are based on interstadial/interglacial units, palaeosols and lacustrine organic layers interbedded with glacigenic deposits, and on pedostratigraphy. Mapping of morphological features and associated marginal and sub-glacial deposit facies was used to characterize and reconstruct glacial margin fluctuations. Based on the field evidence, the stratigraphical limits recognized at single sites can be interpolated over the whole amphitheatre. Ten stratigraphic units (referred to as alloformations: Afs) were distinguished and mapped. They are related to at least as many glacial episodes ranging in age from the end of the Early Pleistocene to the Late Pleistocene. The youngest three glacial units (Serra Af, Piverone Af and Ivrea Af) and one interstadial level (Alice Superiore Unit between Serra and Piverone Afs) are discussed in detail. Based on biostratigraphical and pedological, as well as sedimentological and morphological data, the Serra Af can be attributed to MIS 6 and Piverone Af to MIS 4. The 10Be surface exposure ages from two boulders (27.9±3.1, 32.4±4.0kyr) on the Serra d’Ivrea moraine provide only a minimum age for moraine construction. The alignment of typical ice marginal landforms (moraines and kame terraces) for the more recent unit (Ivrea Af) has allowed recognition of 12 principal stadials during the LGM and Lateglacial; 6 stadials in the amphitheatre and 6 stadials in Dora Baltea Valley, and reconstruction of the nature of the last glacial retreat from the amphitheatre to the cirques. 10Be exposure ages from three boulders related to Ivrea Af are 13.1±1.0, 17.4±2.6 and 20.8±1.5ka. The latter two ages indicate that the Dora Baltea Glacier deposited the Ivrea Af in the IA during MIS 2. The 10Be exposure ages of 14.6±1.2 and 14.0±0.9ka from a polished bedrock surface some 15km upstream from the amphitheatre provide a minimum age for ice decay. [Copyright &y& Elsevier]

Abstract: New geologic mapping of the area near Castellamonte (Torino Province) describes a wide Plio-Quaternary continental succession, up to about 100-m thick. This sequence is distinguished according to allostratigraphic criteria. Altitude, degree of pedogenesis and sediment supply from different basins are also used. Within a single alloformation, several lithofacies are described. Fine-grained fan-delta sediments (Vespia Alloformation) are described in the lower part of the continental succession. The fossil plant remains indicate an Early–Middle Pliocene age. These sediments show an evident deformation and fill ancient lacustrine basins, likely associated with the Canavese Line trend. Their wide distribution and considerable thickness suggest subsidence. Coarse-grained glacial, outwash and fluvial sediments (Colleretto Castelnuovo, S. Defendente, Case Musso, Pagliero, Serra and Piverone Alloformations) are described in the upper part of the continental succession. They consist of undeformed sediments deposited during Middle to Late Pleistocene. These sediments indicate the presence of small local glaciers along the current valley trends. The terracing ratios among the different units and their small thicknesses indicate subsequent differential uplift. [Copyright &y& Elsevier]

• Construction of a thermal model of the vertical temperature distribution in the shallow aquifer. • Variable temperature zone is identified in 0–25 m depth range in NW Italy alluvial plain. • Constant temperature zone is identified in 25–50 m depth range in NW Italy alluvial plain. • Elaboration of simple equations useful to design geothermal systems in the western Po Plain. This study analyses the temperature distribution underneath the Piedmont Po Plain (NW Italy), where an important shallow aquifer exists due to fluvial and outwash deposits. A total of 118 thermal logs, for a total of 513 temperature measurements in spring 2008 and 585 in autumn 2008, were used to propose the conceptual thermal model of the vertical temperature distribution in the shallow aquifer of the western Po Plain. A constant temperature depth between 30 and 50 m below ground level was observed, under which aquifer temperatures were constant in the range 13−15 °C during the year independent of the external climatic condition. Above the constant temperature depth, the variable temperature zone , where the temperature is strongly influenced by external seasonal variations, was observed. Moreover, the collected thermometric data were processed, and the solution to the heat diffusion equation underground allowed us to determine the average distribution of temperature at different depths over time. This study provides a more detailed conceptual model of the temperature distribution in the Piedmont Po Plain. The model can be applied to other areas with similar hydrogeological characteristics (e.g., the eastern Po Plain or large plain alluvial aquifers). The paper also furnishes a description of the physical processes of heat diffusion in the shallow aquifer, as supported by statistical analysis. The proposed methodology may be adopted as a simple statistical method for the assessment of temperature values for the low-enthalpy geothermal exploitation of groundwater resources. [ABSTRACT FROM AUTHOR]

Abstract: A Pleistocene terraced fluvial succession is found on the northern slope of the Torino Hill. This succession consists of many relics of flat surfaces, separated by scarps, often associated with sandy and silty deposits, perched from 30 to 400m on the Po Plain. Terraced surfaces at high levels are more deformed, dissected and mostly deprived of their original sediments; lower ones are less deformed, more continuous and preserved. In the western sector of the area, these surfaces form a declining terraced succession towards the plain. In the eastern sector they form a terraced succession entrenched within the relief. The succession is not linked either to the present hilly watercourses, or to the Po River now developed to the north of hilly relief, because during the Pleistocene the river flowed south of the Torino Hill. On the contrary, it is connected with modification by ancient Northern Piemonte Plain watercourses. This succession is the result of deformation of original plain sectors prior to the Po River shifting north of the relief. The comparison of chronological reference of fluvial morphological features and sediments with their altimetric distribution, suggests a mean uplift of the Torino Hill of about 1mm/year. The present morphology connected with this evolution favours landslide phenomena. [Copyright &y& Elsevier]