409 research outputs found
Characterization and possible hazard of an atypical asbestiform sepiolite associated with aliphatic hydrocarbons from Sassello (Ligurian Apennines, Italy)
Low-temperature, diagenetic serpentinization of peridotite clasts in lower Miocene marine conglomerates, Torino Hill, NW Italy
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Juvenile social relationships reflect adult patterns of behavior in wild geladas
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/113724/1/ajp22443.pd
Conditions of ore formation at the Gorno MVT deposits (Lombardy, Italy): insights from fluid inclusions
Gorno mining district (Southern Alps): new preliminary data about ore mineral precipitation and multiphase diagenetic evolution
U-pb dating and geochemical constraints to Early Cretaceous hydrothermal dolomitization in the Provençal domain (Maritime alps, NW Italy-SE France)
Ornamental Stones of Piemonte (NW Italy): an updated geo-lithological map
The 'Ornamental Stones of Piemonte Region' geo-lithological map at 1:250,000 scale aims at reviewing the ornamental stone heritage of Piemonte at the regional scale. The map derives from a thorough revision of the available literature, integrated with some unpublished original data. The map shows the location of the main quarries of ornamental stones of the region, selected on the basis of their historical, cultural and architectonic relevance. A geo-lithological basemap was produced, deriving it from a basic Geological Map of Piemonte, available at the same scale. The large varieties of lithotypes of Piemonte have been resumed, in the new map, into 21 classes, which all the ornamental stones have been assigned to. The Main Map is enriched by some significant examples of using the ornamental stones in historical buildings, and it is supported by a supplementary data base containing essential information about the quarry sites and the quarried material
Late metamorphic veins with dominant PS-15 polygonal serpentine in the Monte Avic ultramafite
The ultramafic body of Monte Avic (Aosta Valley, Western Alps,
Italy) consists of antigorite serpentinite and Ti-clinohumite metadunite.
They host late metamorphic veins, up to a couple of centimeters thick,
compact, and homogeneous, with a “porcelain” appearance. Vein colors range
from yellowish to light greenish, light yellowish fading to white, or rare
orange. The veins consist of 15-sector PS-15 polygonal serpentine,
with chemical composition Mg2.85 Fe0.08 Si2.05 O7.05
[OH]3.95. Recognition of this unusual phase is supported by diagnostic
satellite reflections in the X-ray powder diffraction pattern (e.g., at
dobs of 2.502, 2.336, 2.151, and 1.966 Å) TEM images (showing
15-sector polygonal fibers, mostly 200 nm in diameter and a few µm in
length, forming a randomly oriented felt) and a µ-Raman wavenumber,
matching previous data. This different evidence affords the successful
distinction of PS-15 and PS-30, alternatively using TEM images, X-ray powder
diffraction, or the low- and high-wavenumber µ-Raman spectra. At Monte
Avic, the vein emplacement was accompanied by significant fluid pressure, as
suggested by deformation and dismembering of the host rock, with PS-15 grown
within isotropic stress microenvironments characterized by fluid-filled
voids. Random growth of the mass-fiber polygonal serpentine was favored by
low-strain conditions. PS-15 veins formed at the end of the long polyphase
Alpine orogenic evolution, with hydrous fluids possibly deriving from
serpentinite dehydration in the depth.</p
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