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Information on palaeoclimate is encoded in groundwater in a variety of measurable “tracers”. A great variety of geochemical and isotopic methods has been developed and tested with the aim of defining the different moments and aspects of the water cycle, providing a fundamental information on the recharge and groundwater flow conditions. Furthermore, environmental tracers allow us to reconstruct past environmental changes. Particular emphasis is put on Western Africa and on the Po valley. In fact, two features are common to these regions: the movement of air masses crossing them and the geological characteristics. From the global perspective, Sahel, North Africa, Mediterranean Basin and Central Europe reveal a relative simple pattern of spatial and temporal composition of precipitation. The displacement of the Intertropical Convergence Zone (ITCZ) and the Azores anticyclone control the climatological regime and, consequently, the isotopic composition of rainfall. Moreover, both regions are characterised by big aquifers in the form of multilayer systems several hundred metres thick in large sedimentary basins. The aquifers are generally formed by sandstones (Sahara) or sands (Po valley) and are interbedded with argillaceous layers and outcrop only in fairly limited areas, constituting the recharge zones. The groundwater movement in confined aquifers is always lower than 1 m year-1, respecting the conditions of steady-state flow regime and hydraulic continuity, necessary for the “hydro-archives”. The comparison between the Sahara–Sahel and southern Alps allows to define the principal periods of aquifer replenishment associated with the displacement of the Intertropical Convergence Zone (ITCZ) and the Azores anticyclone. Continental isotope archives provide a means of extending the knowledge on the magnitude and the causes of environmental and climate changes. Nevertheless, for a quantitative interpretation of the isotope records preserved in continental archives, it is necessary to know the response of the isotopic composition of precipitation to long-term fluctuations in key climatic parameters over a given area. Further, the transfer functions relating the climate-induced changes of the isotopic composition of precipitation to the isotope record preserved in the given archive should be established. It appears, thus, that stable isotopes can, presently only be used as an indirect proxy dating method for palaeowaters.

Nella presente nota sono descritti i risultati di una ricerca sulle caratteristiche idrochimiche delle acque di sorgente emergenti dai corpidi frana che interessano i fianchi della dorsale anticlinalica di M. Pietralata – M. Paganuccio. Il collasso gravitativo di gran parte deifianchi della dorsale, legato principalmente all’assetto morfostrutturale e litostratigrafico dell’area, coinvolge generalmenteil substratoe ha prodotto vasti e spessi accumuli di frana, variamente dislocati e disarticolati. Le masse franate, avendo sviluppato una elevatapermeabilità secondaria, hanno costituito acquiferi propri e sensibilmente condizionato la circolazione idrica sotterranea più superfi-ciale. Ciò ha generato numerosi punti di scaturigine distribuiti sia alla base del rilievo, ai margini dei principali corpi di frana, sia all’in-terno dei corpi stessi. In certi casi, invece, gli accumuli di frana probabilmente ricoprono sorgenti legate a circuiti più profondi, all’in-terno delle rocce del substrato. I risultati delle analisi chimiche effettuate sulle acque di sorgente nelle campagne di monitoraggio del1984 e del 2004, oltre a caratterizzare facies idrochimiche sub-superficiali direttamente legate ai corpi di frana, sottolineano propriouna loro probabile miscelazione con acque di provenienza più profonda. Geological-geomorphological and hydrochemical studies have been carried out throughout the anticline ridge of Pietralata-PaganuccioMts. (northern Umbria-Marche Apennines, Central Italy) in order to find a possible correlation between the large landslides almostaffecting the entire mountain flanks and spring-water characteristics. The study area embraces the northernmost sector of a much lon-ger calcareous anticline ridge extending all along the Marche Region. The Furlo Gorge, a narrow transverse canyon deeply cut bytheCandigliano River (Metauro River basin), breaches the anticline ridge separating the two mountains from each other. This sectorof theridge, although rather simple as for its morphostructure, is indeed one of the most important examples of such landforms so characte-ristic of the Umbria-Marche Apennines. Pietralata and Paganuccio Mts. consist of the mostly calcareous and marly-calcareous Meso-Cenozoic units of the Umbria-Marche Succession. The Jurassic-Cretaceous terrains, ranging from the Calcare Massiccio Fm. and theScaglia Bianca Fm., crop out in the Furlo Gorge area only, deeply cut in its turn at the core of the anticline. The flanks and the crest ofthe anticline ridge, on the contrary, are made up of Createceous-Oligocene terrains, namely Scaglia Rossa-Scaglia Cinerea andBisciaro Fms. Pietralata and Paganuccio Mts. are an explicatory example of an exhumed anticline, where the geological structureisdistinctly replicated by the relief topography. Indeed, the ridge morphology almost perfectly displays both the rounded geometry of theanticline and its northwestern and southeastern plunge-out areas. Furthermore, characteristic flat top-surfaces markedly reflect thesub-horizontal/gently-dipping bedding of the hinge zone, while the mountain sides slope at angles approximating the downslope-dip-ping layering values. Although the peculiar morphostructural arrangement of the ridge has been shaped by different processes, the roleof large, deep-seated mass movements is once more today among the most effective ones. Landslides, affecting both sides of theridge for the most part, find their key predisposing factors in the dip-slope layering attitude on the two sides of the anticline ridge, aswell as in the occurrence of weak marly horizons (e.g. Marne a Fucoidi Fm., marly members of Scaglia Rossa Fm., etc.),embeddedamong calcareous units in different stratigraphic positions. The occurrence of an intense local rock-fracturing is an effectiveadditionalpredisposing factor. As a result, the most part of the anticline ridge flanks have been extensively denudated by more or less shallowlandsliding, able to highlight both lithologic contrasts of the Jurassic-Miocene “multilayer” and structural features, such as fault-zonesand bended bedding surfaces. The gravitational sagging and collapse of the anticline flanks encompass several, different field eviden-ce. As a rule, the landslide head areas display tension cracks and more or less distinct trenches, scarps and counterslopes; the slidmass becoming more and more disrupted and chaotic downslope, where an over-100m thickness is often reached and stressed bydeep gully dissection of the landslide mass. Indeed, the substantial permeability acquired by progressive fracturing of the sliding rockbodies allows for a great number of frequently perennial aquifers and springs to occur within the slid-bodies and/or at the toeof themajor landslides. On the contrary, in some places, the landslide materials have probably blanketed some springs related to relativelydeep bedrock aquifers. Hydrochemical data show that the characteristics of the majority of the analysed waters set in the fieldof Ca2+ -HCO3-compositions, with two different trends, namely “A”, trending towards Na+- Cl-compositions, and “B”, trending towards Ca2+-SO42-compositions. A possible reason of these two trends is the mixing of superficial water circulating inside the landslide masses withwaters flowing out from deeper bedrock-aquifers. Water samples from the Pietralata Mt. area, according to the most part of watersfrom carbonatic rocks of the Marche Region, display contents in Ca2+, Mg2+and HCO3-which are mostly due to magnesian-calcite solu-tion or, alternatively, to a mixing of calcite and dolomite (this latter, especially for waters from relatively deep aquifers). As regards watersaturation in calcite at different PCO2conditions, the analysed samples display a range of values approximating those typical for soils(0.15 bar). Being such values much higher than those already reported for carbonate aquifers of Nerone Mt. (0.0003 – 0.003 bar), anear-surface water circulation can be alleged. In this respect, a similar assumption can be drawn from both the relatively low dischar-ges of the studied springs, and from the recurring traces of NO3-concentration. As regards this latter, in particular, its relatively highconcentration in both 1984 and 2004 samplings is likely to be related to both biologic activity and humification (nitrification) on the sur-face of the slid-masses, although a less important amount of NO3-from fertilizers cannot be ruled out. Moreover, a low Ca2+- SO42-composition of the samples at issue can be related to the mixing of relatively deep waters from bedrock aquifers whose springs areblanketed by thick landslide accumulations. Finally, the observed trend “A”, towards Na+ - Cl- compositions, can be ascribed tocyclicsalts coming from near marine areas.

A protein S gene polymorphism, detectable by restriction analysis (BstXI) of amplified exonic sequences (exon 15), was studied in seven Italian families with protein S deficiency. In the 17 individuals heterozygous for the polymorphism the study was extended to platelet mRNA through reverse transcription, amplification and densitometric analysis. mRNA produced by the putative defective protein S genes was absent in three families and reduced to a different extent (as expressed by altered allelic ratios) in four families. The allelic ratios helped to distinguish total protein S deficiency (type I) for free protein S deficiency (type IIa) in families with equivocal phenotypes. This study indicates that the study of platelet mRNA, in association with phenotypic analysis based upon protein S assays in plasma, helps to classify patients with protein S deficiency.