A conceptual hydrogeological model of ophiolitic aquifers (serpentinised peridotite): The test example of Mt. Prinzera (Northern Italy)          下载免费PDF全文

Stefano Segadelli  Paolo Vescovi  Kei Ogata  Alessandro Chelli  Andrea Zanini  Tiziano Boschetti  Emma Petrella  Lorenzo Toscani  Alessandro Gargini  Fulvio Celico 《水文研究》2017,31(5):1058-1073

The main aim of this study is the experimental analysis of the hydrogeological behaviour of the Mt. Prinzera ultramafic massif in the northern Apennines, Italy. The analysed multidisciplinary database has been acquired through (a) geologic and structural survey; (b) geomorphologic survey; (c) hydrogeological monitoring; (d) physico‐chemical analyses; and (e) isotopic analyses. The ultramafic medium is made of several lithological units, tectonically overlapped. Between them, a low‐permeability, discontinuous unit has been identified. This unit behaves as an aquitard and causes a perched groundwater to temporary flow within the upper medium, close to the surface. This perched groundwater flows out along several structurally controlled depressions, and then several high‐altitude temporary springs can be observed during recharge, together with several perennial basal (i.e., low altitude) springs, caused by the compartmentalisation of the system because of high‐angle tectonic discontinuities.  相似文献   

Waves generated by a moving point-source within a finite-depth ocean     

Paolo Lanzano 《Earth, Moon, and Planets》1991,52(3):233-252

We consider a flat ocean of finite depth h consisting of an inviscid, incompressible fluid with no surface tension. A source of constant strength moves uniformly in a horizontal direction at a constant depth. We study the wake generated by this moving disturbance.Using the Fourier transform approach, we determine the unique velocity potential for this irrotational, steady motion, subject to the bottom and free-surface boundary conditions and to its vanishing at infinity.  相似文献   

Weak stability boundary trajectories for the deployment of lunar spacecraft constellations     

Christian Circi  Paolo Teofilatto 《Celestial Mechanics and Dynamical Astronomy》2006,95(1-4):371-390

Suitable lunar constellation coverage can be obtained by separating the satellites in inclinations and node angles. It is shown in the paper that a relevant saving of velocity variation ΔV can be achieved using weak stability boundary trajectories. The weakly stable dynamics of such transfers allows the separation of the satellites from the nominal orbit to the required orbit planes with a small amount of ΔV. This paper also shows that only one different set of orbital parameters at Moon can be reached with the same ΔV manoeuvre starting from a nominal trajectory and ending at a fixed periselenium altitude. In fact, such a feature is proved to be common to other simpler dynamical systems, such as the two- and three-body problems.  相似文献   

The classification of BL Lacertae objects: the Ca H&K break     

Hermine Landt  Paolo Padovani †‡  Paolo Giommi 《Monthly notices of the Royal Astronomical Society》2002,336(3):945-956

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Zn and Pb mobility during metamorphism of sedimentary rocks and potential implications for some base metal deposits     

Johannes Hammerli  Carl Spandler  Nicholas H.S. Oliver  Paolo Sossi  Gregory M Dipple 《Mineralium Deposita》2015,50(6):657-664

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A general framework for the simulation of geochemical compaction     

Bianca Giovanardi  Anna Scotti  Luca Formaggia  Paolo Ruffo 《Computational Geosciences》2015,19(5):1027-1046

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Excavation works in stiff jointed clay material: examples from the Trubi formation,southern Italy     

David Segato  Giuseppe Scarpelli  Viviene M. E. Fruzzetti  Paolo Ruggeri  Alessandro Vita  Alessandra Paternesi 《Landslides》2015,12(4):721-730

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Thermoluminescence dating of the Kamil impact crater (Egypt)          下载免费PDF全文

Gian Paolo Sighinolfi  Emanuela Sibilia  Gabriele Contini  Marco Martini 《Meteoritics & planetary science》2015,50(2):204-213

Thermoluminescence (TL) dating has been used to determine the age of the meteorite impact crater at Gebel Kamil (Egyptian Sahara). Previous studies suggested that the 45 m diameter structure was produced by a fall in recent times (less than 5000 years ago) of an iron meteorite impactor into quartz‐arenites and siltstones belonging to the Lower Cretaceous Gilf Kebir Formation. The impact caused the complete fragmentation of the impactor, and the formation of a variety of impactites (e.g., partially vitrified dark and light materials) present as ejecta within the crater and in the surrounding area. After a series of tests to evaluate the TL properties of different materials including shocked intra‐crater target rocks and different types of ejecta, we selected a suite of light‐colored ejecta that showed evidence of strong thermal shock effects (e.g., partial vitrification and the presence of high‐temperature and ‐pressure silica phases). The abundance of quartz in the target rocks, including the vitrified impactites, allowed TL dating to be undertaken. The variability of radioactivity of the intracrateric target rocks and the lack of direct in situ dosimetric evaluations prevented precise dating; it was, however, possible to constrain the impact in the 2000 BC–500 AD range. If, as we believe, the radioactivity measured in the fallback deposits is a reliable estimate of the mean radioactivity of the site, the narrower range 1600–400 BC (at the 2σ confidence level) can be realistically proposed.  相似文献   

Systematic conservation planning in the Mediterranean: a flexible tool for the identification of no-take marine protected areas     

Maiorano  Luigi; Bartolino  Valerio; Colloca  Francesco; Abella  Alvaro; Belluscio  Andrea; Carpentieri  Paolo; Criscoli  Alessandro; Jona Lasinio  Giovanna; Mannini  Alessandro; Pranovi  Fabio; Reale  Bruno; Relini  Giulio; Viva  Claudio; Ardizzone  Gian Domenico 《ICES Journal of Marine Science》2009,66(1):137-146

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Structural trends and palaeogeography of the central and western Sicily belt: new insights     

Raimondo Catalano  Piero Di  Stefano Francesco Paolo Vitale 《地学学报》1995,7(2):189-199

The geology of the Sicilian mainland is summarized by N–S geological sections. A continuous late Cenozoic orogenic belt through central and western Sicily resulted from a complex deformative history, recorded by several tectonic events. The deformation mainly involved the sedimentary cover of the old African continental margin, formed in a large basinal area, bordered at its southern margin by a shallow-water carbonate environment attached to Gondwana. The orogenic belt involves a complex architecture of thrust systems, of different size, geometry and palaeogeographical origin. Deformation, which mainly developed in the earlier stages of thrusting in the basinal rock assemblages, mainly gave rise to a stack of three different duplex structures, respectively, composed of Palaeozoic, Mesozoic–Palaeogene and Neogene strata. Large-scale clockwise rotation of the thrusts predated transpressional movements in the hinterland during the latest Miocene to Pliocene. High- angle reverse faults, with lateral components, modified earlier tectonic contacts within the allochthons. Contemporaneous southwards- directed imbrications affected the external southern areas, progressively incorporating foreland and piggyback basirts. The stratigraphic relationships of basin-fills to the tectonic structures reveals that reactivation processes have been active during the last Plio-Pleistocene.  相似文献