66 research outputs found
The Meso–Cenozoic stratigraphic succession of the Col de Braus area (Maritime Alps, SE France)
STRATIGRAPHY, SEDIMENTOLOGY AND SYNDEPOSITIONAL TECTONICS OF THE JURASSIC-CRETACEOUS SUCCESSION AT THE TRANSITION BETWEEN PROVENÇAL AND DAUPHINOIS DOMAINS (MARITIME ALPS, NW ITALY)
The Provençal and Dauphinois Mesozoic successions cropping out at the southeastern margin of the Argentera Massif (Maritime Alps, NW Italy) were deposited at the transition between the Provençal platform and the Dauphinois basin, marked in the study area by a partly preserved Mesozoic palaeoescarpment. These successions show important lateral variations occurring over relatively short distances, probably related to syndepositional tectonics. Different stratigraphic intervals of the pelagic-hemipelagic Dauphinois succession contain resedimented deposits, made up of both intra- and extrabasinal material, which provide a twofold evidence of syndepositional tectonics indicating both tectonically-triggered gravitational processes and a tectonically-driven evolution of the source areas. Two stages of syndepositional tectonics have been recognized: the first in the earliest Cretaceous, which is related to the deposition of carbonate breccias in the Dauphinois succession and to hydrothermal dolomitization of the Middle Triassic-Jurassic Provençal carbonates, and the second in the Late Cretaceous, which triggered the deposition of different detrital lithozones in the Upper Cretaceous Puriac Limestone. The cited evidence indicates that syndepositional tectonics continued to influence the evolution of the Alpine Tethys European passive margin long after the Late Triassic-Early Jurassic syn-rift stage, which caused the differentiation between the Dauphinois basin and the Provençal platform
The Neolithic greenstone industry of Chiomonte (northwestern Italy): mineralogy, petrography and archaeometric implications
Abstract. The polished stone industry of Chiomonte (Piedmont
region, northwestern Italy), dating back to the middle to late Neolithic,
has been studied with a multi-analytical approach, including mineralogical,
petrographic and morpho-typological issues, with the aim of providing
information about the sources of the raw materials and determining
the function of this particular settlement in the prehistoric Western Alps. Most
of the lithic tools are made of sensu stricto greenstones (i.e.
"Na pyroxene rocks" and "Na pyroxene and garnet rocks"), though a large
number of serpentinite tools (25 %) also exist. The combined application of
X-ray powder diffraction (XRPD), polarising microscopy and Scanning Electron Microscopy coupled with Energy Dispersive Spectrometry (SEM-EDS) led to the detection of specific
mineral and chemical "markers", pointing to the Chiomonte
tools likely having come from the Monviso area. However, other closer supply sources, e.g.
small meta-ophiolite units in the Orsiera–Rocciavré mountain range or in
the lower Susa valley, cannot be ruled out. The presence, on the many
retrieved roughouts and broken tools, of raw, yet unpolished surfaces
that are ascribable to pebbles and cobbles from alluvial or glacial deposits,
suggests that these rocks had been picked up from local "secondary" sources.
The abundance of roughouts and broken tools identifies Chiomonte as a
second-order manufacturing site, although it is still unclear whether such
an activity was restricted to serving local needs or if it contributed to the
circulation of greenstone implements on a wider scale
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