Please use this identifier to cite or link to this item:
Authors: Marchesini, Barbara* 
Carminati, Eugenio* 
Aldega, Luca* 
Mirabella, Francesco* 
Petrelli, Maurizio* 
Caracausi, Antonio* 
Barchi, Massimiliano Rinaldo* 
Title: Chemical interaction driven by deep fluids in the damage zone of a seismogenic carbonate fault
Journal: Journal of Structural Geology 
Series/Report no.: /161 (2022)
Publisher: Elsevier
Issue Date: 2022
DOI: 10.1016/j.jsg.2022.104668
Keywords: fluids
Gubbio Fault
noble gases
Abstract: We analyzed from meso-to microscale the chemical interaction (e.g., bleaching) between deep fluids and carbonate rocks in pelagic limestones exposed along the seismically active Gubbio normal fault (Northern Apennines), exhumed from ca. 2 km depth. Bleaching is enhanced by the exploitation of inherited stylolitic seams by fluids and is favored by the progressive leaching and mobilization of primary components (i.e., Ca, Fe, Pb, and Cu) and the precipitation of authigenic baryte due to temperature and/or redox potential contrast. Analysis of fluid inclusions trapped in calcite veins in the damage zone precipitated from a H2O–NaCl-bearing fluid(s), with low salinity (1.22–2.57 wt%NaCleq) and a range of trapping temperature between 107 ◦C and 185 ◦C, higher than the host rock peak T conditions. Analysis of fluid inclusions and noble gases from syn-kinematic calcite and mineralogy of altered rocks suggests a mixed contribution between crustal-derived fluids with diagenetic fluids containing sulphates and CO2. We speculate that bleaching is a by-product of the circulation of such aggressive fluids with mixed contributions, likely mobilized during seismic event(s) and injected into the damage zone at shallow depths. Such processes, affecting the chemical-physical properties of limestones, are generally underestimated and should be considered when modelling hydraulic connectivity in fractured carbonate reservoirs.
Appears in Collections:Article published / in press

Files in This Item:
File Description SizeFormat Existing users please Login
Marchesini et al., 2022_JStructurGeol.pdfRestricted Paper22.26 MBAdobe PDF
Manoscritto Febbraio_submited.pdf26.83 MBAdobe PDFView/Open
Show full item record

Page view(s)

checked on Mar 25, 2023


checked on Mar 25, 2023

Google ScholarTM