Val Vedello

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P.zo Gro fault

Great reverse fault of Alpine age, E-W direct, N dipping, ever signalled by some, present both on the right and on the left  of the Val Vedello that cuts transversally .

It is deducible in field for the big topographical jump of the stratigraphic limits  (metamorphic rocks - Collio Formation ) in the high  part of the same valley (dx).  It is located more to south of the “Pizzo Cavrin” fault, smaller, placed in the hanging valley  that separates the two cited tops.

The Pizzo Gro fault he hides under an enormous fan of debris, by it produced, that   from the bottom valley reach the watershed with the Seriana Valley (Bocchetta dei Geroi),  grazing to south, the Pizzo Gro top, for then “to disguise"  in an undifferentiated  and monotonous sedimentary Collio Formation almost racing parallel to the topographic surface of the high Costa dell' Aser.

In underground the fault has been crossed by a  tunnel direct north-south traced in the Morbegno Gneisses. Are been crossed a lot of ten meters of mylonite and cataclasities / ultracataclasite rocks of dark color with notable enrichments of iron and copper sulphide ore.

The horizontal displacement of this fault - perfectly measured by exploratory drillings- it is on the order of the five hundred meters.  It is not known if to this corresponds an as many vertical or also to trascurrent displacement. Nobody, with a deepned ceck of the kinematic-guides, has ever studied possible presences or effects of right trascurrent of Alpine strain or ancestral inheritance of the Collio basin (strike-slip faults in pull apart basin).

As already says, the Pizzo Gro fault dramatically displace  the formational boundary on the right  slope of the Val Vedello but, apparently  it doesn' t do  as many on the left, on the oriental sides of Pizzo Ceric, where the formational boundary   is not at all notched from there.

How? To demonstration of the skin-deep of the geologic and structural studies  ducts, none of the previous “researchers” it is never asked the question and it has considering the formational boundary - exposed on the oriental slopes of the Pizzo Ceric - as normal limit.

Nobody has ever asked how this limit dips in antithesis, exactly contrary to that outcropping on the other slope of the valley  what it doesn't show any jumps  of the formational boundary   produced by the  Alpine E-W  reverse faults that characterizes the right slope of the valley . Additionally the petrographic and radiometric facies of this formational boundary are well different besides from those observed on the right slope of the  Val Vedello.

The thing perfectly explainable considering this formational boundary not as normal limit but as tectonic limit, produced by a direct fault of back age to the reverse tectonic. All the Val Vedello it brings dramatic stratigraphic  and morphologic evidences of this.