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101.
The Monte Orfano Conglomerate revisited: stratigraphic constraints on Cenozoic tectonic uplift of the Southern Alps (Lombardy, northern Italy) 总被引:1,自引:0,他引:1
Dario Sciunnach Giancarlo Scardia Fabrizio Tremolada Isabella Premoli Silva 《International Journal of Earth Sciences》2010,99(6):1335-1355
The Monte Orfano Conglomerate (MOC), exposed in the foothills of the Southern Alps (northern Italy), is one of the few outcrops
of sediments documenting the Cenozoic tectonic evolution of the Alpine retrowedge. Calcareous nannofossil biostratigraphy
allowed us to constrain the upper part of the MOC, formerly attributed to the Early-Middle Miocene in the type-locality, to
the earliest Miocene (Neogene part of the NN1 nannofossil zone). A likely latest Oligocene age is therefore suggested for
the bulk of the underlying conglomerates, whose base is not exposed. Deposition of the MOC can be placed within the post-collisional
tectonic uplift of the Alps, documented in the Lake Como area by the Como Conglomerate (CC) at the base of the Gonfolite Lombarda
Group, and supports the correlation with Upper Oligocene clastic sediments cropping out further to the East, in the Lake Garda
and in the Veneto-Friuli areas (“molassa”). The remarkable difference in petrographic composition between the western (CC) and eastern (MOC) clastics deposited in
the Alpine retro-foreland basin highlights the synchronous tectonic activity of two structural domains involving different
crustal levels. Whilst the bulk of the CC, that straddles the Oligocene/Miocene boundary, records largely the tectonic exhumation
of the Alpine axial chain crystalline complexes, the coeval MOC consists of detritus derived from the superficial crustal
section (Triassic to Paleogene sedimentary rocks) of the Alpine retrowedge and constrains the onset of the post-collisional
deformation phase of the Southern Alps as not younger than the Late Oligocene. 相似文献
102.
An approximate step-by-step procedure is presented for the finite element analysis of transient unconfined flow problems. At each step the free surface is modelled by means of segments coinciding with sides of the elements. This leads to an approximate but extremely simple solution scheme which can be readily incorporated into standard codes for confined analysis. The solutions of some significant problems are presented and compared with other non-approximate solutions. They show that the technique, in spite of its approximation, is capable of giving meaningful results from an engineering viewpoint. 相似文献
103.
104.
Fossi MC Marsili L Lauriano G Fortuna C Canese S Ancora S Leonzio C Romeo T Merino R Abad E Jiménez B 《Marine environmental research》2004,58(2-5):269-274
Various studies have revealed high concentrations of contaminants such as organochlorines (OCs) and heavy metals in Mediterranean cetaceans. A geographical trend of contamination (PCBs and DDTs) has been found for striped dolphin (Stenella coeruleoalba). In this study we used a non-lethal approach (skin biopsy) to investigate bioaccumulation of OCs, including polychlorobiphenyls (PCBs), DDTs, polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), trace elements (Hg, Cd, Pb) and CYP1A activity (BPMO) in nine striped dolphins sampled in the Aeolian area (Sicily - Italy) in summer 2002. The arithmetic mean value of BPMO activity in this group was 43.46 AUF/g tissue/h. This value is approximately 3 times and 5 times lower, respectively, than the value found in the Ionian and in the Ligurian groups. Skin biopsies of striped dolphins emerged as a suitable material for assessing the toxicological status of the various Mediterranean groups. 相似文献
105.
106.
Daniele Penna Marco Borga Daniele Norbiato Giancarlo Dalla Fontana 《Journal of Hydrology》2009,364(3-4):311-327
107.
108.
Experimental results on limb darkening and specific intensities imply more ultraviolet continuous opacity than that predicted by theoretical calculations. Some atomic and molecular processes, not yet studied from this standpoint are investigated as to their importance on the continuous absorption coefficient. The negative results obtained suggest some arguments about the importance of iron as photo-absorber. 相似文献
109.
A model of the transition layer of an active region of the Sun is presented based on radio observations. The model is deduced by using the Laplace transform of the brightness temperature and the hydrostatic equilibrium equation. A rational function, well-behaved in the coronal region, has been used to represent the observed brightness temperature. The model indicates the existence of a very steep temperature gradient and suggests the presence of a constant conductive flux from the corona into the chromosphere. Both these conclusions are quantitatively in a very good agreement with those deduced from the UV emission lines observations, thus removing a previous discrepancy between radio and optical based models. It is also shown that the presence of a weak magnetic field does not alter the above conclusions. 相似文献
110.
SMART-1 after lunar capture: First results and perspectives 总被引:1,自引:0,他引:1
B. H. Foing G. D. Racca A. Marini E. Evrard L. Stagnaro M. Almeida D. Koschny D. Frew J. Zender D. Heather M. Grande J. Huovelin H. U. Keller A. Nathues J. L. Josset A. Malkki W. Schmidt G. Noci R. Birkl L. Iess Z. Sodnik P. McManamon 《Journal of Earth System Science》2005,114(6):689-697
SMART-1 is a technology demonstration mission for deep space solar electrical propulsion and technologies for the future.
SMART-1 is Europe’s first lunar mission and will contribute to developing an international program of lunar exploration. The
spacecraft was launched on 27th September 2003, as an auxiliary passenger to GTO on Ariane 5, to reach the Moon after a 15-month
cruise, with lunar capture on 15th November 2004, just a week before the International Lunar Conference in Udaipur. SMART-1
carries seven experiments, including three remote sensing instruments used during the mission’s nominal six months and one
year extension in lunar science orbit. These instruments will contribute to key planetary scientific questions, related to
theories of lunar origin and evolution, the global and local crustal composition, the search for cold traps at the lunar poles
and the mapping of potential lunar resources 相似文献