TY  - JOUR
A1  - Barale, Luca
A1  - Bertok, Carlo
A1  - d’Atri, Anna
A1  - Mantovani, Alizia
A1  - Martire, Luca
A1  - Agostini, Samuele
A1  - Bernasconi, Stefano M.
A1  - Gerdes, Axel
A1  - Ferrando, Simona
T1  - Syn-rift hydrothermal circulation in the Mesozoic carbonates of the western Adriatic continental palaeomargin (Western Southalpine Domain, NW Italy)
T2  - Basin research
N2  - Evidence of hydrothermal activity is reported for the Mesozoic pre- and syn-rift successions of the western Adriatic palaeomargin of the Alpine Tethys, preserved in the Western Southalpine Domain (NW Italy). The products of hydrothermal processes are represented by vein and breccia cements, as well as dolomitization and silicification of the host rocks. In the eastern part of the study area, interpreted as part of the necking zone of the continental margin, Middle Triassic dolostones and Lower Jurassic sediments are crossed by veins and hydrofracturing breccias cemented by saddle dolomite. The precipitation of dolomite cements occurred within the stratigraphic succession close to the sediment–water interface. Despite the shallow burial depth, fluid inclusion microthermometry and clumped isotopes show that hydrothermal fluids were relatively hot (80–150°C). In the western part of the study area, interpreted as part of the hyperextended distal zone, a polyphase history of host-rock fracturing is recorded, with at least two generations of veins cemented by calcite, dolomite and quartz. Vein opening and cementation occurred at shallow burial depth around the time of deposition of the syn-rift clastic succession. Fluid inclusion microthermometry on both quartz and dolomite cements indicates a fluid temperature of 90–130°C, again pointing to hydrothermal fluids. Both in Fenera-Sostegno and Montalto Dora areas, O, C and Sr isotope values, coupled with fluid inclusion and clumped isotope data, indicate that hydrothermal fluids derived from seawater interacted with crustal rocks during hydrothermal circulation. Stratigraphic and petrographic evidence, and U–Pb dating of dolomitized clasts within syn-rift sediments, document that hydrothermal fluids circulated through sediments from the latest Triassic to the Toarcian, corresponding to the entire syn-rift evolution of the western portion of the Adriatic palaeomargin. The documented hydrothermal processes are temporally correlated with regional-scale thermal events that took place in the same time interval at deeper crustal levels.
KW  - fault-related fluid circulation
KW  - hydrothermal fluids
KW  - hyperextended distal margin
KW  - necking zone
KW  - Southalpine Domain
Y1  - 2021
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/63922
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-639221
SN  - 1365-2117
N1  - Funding information: University of Torino; Compagnia di San Paolo; National Research Council of Italy, Institute of Geosciences and Earth Resources, Torino Unit
VL  - 33
IS  - 6
SP  - 3045
EP  - 3076
PB  - Wiley-Blackwell
CY  - Oxford [u.a.]
ER  -