Vein development during folding in the upper brittle crust: The case of tourmaline-rich veins of eastern Elba Island, northern Tyrrhenian Sea, Italy

Francesco Mazzarini, Giovanni Musumeci, Alexander Cruden

    Research output: Contribution to journalArticleResearchpeer-review

    21 Citations (Scopus)

    Abstract

    Detailed structural analysis of tourmaline-rich veins hosted in the contact aureole of the similar to 6 Ma Porto Azzurro granite in southeastern Elba Island, northern Tyrrhenian Sea is presented. Using geometric features of the veins, the physical conditions at the time of vein formation are estimated, namely the stress ratio (Phi = (sigma(2) - sigma(3))/(sigma(1) - sigma(3))), driving stress ratio (R = (P(f) - sigma(3))/(sigma(1) - sigma(3))) and fluid overpressure (Delta P(o) = P(f) - sigma(3)). Two vein sets (A veins and B veins) have been recognized based on orientation and thickness distributions and infilling material. Analysis of vein pole distributions indicates Phi = 0.57 and R = 0.24 for the A veins and Phi = 0.58 and R = 0.47 for the B veins, and fluid pressures less than the intermediate stress magnitude. Analysis of geometric features of the veins gives estimated fluid over-pressures of between similar to 16 MPa (A veins) and similar to 32 MPa (B veins). We propose a model for the tectonic environment of vein development, in which formation of secondary permeability in the deforming thermal aureole of the Porto Azzurro pluton was controlled by ongoing development of fracture systems in the hinge zone of a regional NNW-SSE trending fold that favored transport and localization of hydrothermal fluids.
    Original languageEnglish
    Pages (from-to)1509 - 1522
    Number of pages14
    JournalJournal of Structural Geology
    Volume33
    Issue number10
    DOIs
    Publication statusPublished - 2011

    Cite this

    @article{822f6628c8214e3997d4ca0c2899476e,
    title = "Vein development during folding in the upper brittle crust: The case of tourmaline-rich veins of eastern Elba Island, northern Tyrrhenian Sea, Italy",
    abstract = "Detailed structural analysis of tourmaline-rich veins hosted in the contact aureole of the similar to 6 Ma Porto Azzurro granite in southeastern Elba Island, northern Tyrrhenian Sea is presented. Using geometric features of the veins, the physical conditions at the time of vein formation are estimated, namely the stress ratio (Phi = (sigma(2) - sigma(3))/(sigma(1) - sigma(3))), driving stress ratio (R = (P(f) - sigma(3))/(sigma(1) - sigma(3))) and fluid overpressure (Delta P(o) = P(f) - sigma(3)). Two vein sets (A veins and B veins) have been recognized based on orientation and thickness distributions and infilling material. Analysis of vein pole distributions indicates Phi = 0.57 and R = 0.24 for the A veins and Phi = 0.58 and R = 0.47 for the B veins, and fluid pressures less than the intermediate stress magnitude. Analysis of geometric features of the veins gives estimated fluid over-pressures of between similar to 16 MPa (A veins) and similar to 32 MPa (B veins). We propose a model for the tectonic environment of vein development, in which formation of secondary permeability in the deforming thermal aureole of the Porto Azzurro pluton was controlled by ongoing development of fracture systems in the hinge zone of a regional NNW-SSE trending fold that favored transport and localization of hydrothermal fluids.",
    author = "Francesco Mazzarini and Giovanni Musumeci and Alexander Cruden",
    year = "2011",
    doi = "10.1016/j.jsg.2011.07.001",
    language = "English",
    volume = "33",
    pages = "1509 -- 1522",
    journal = "Journal of Structural Geology",
    issn = "0191-8141",
    publisher = "Pergamon",
    number = "10",

    }

    Vein development during folding in the upper brittle crust: The case of tourmaline-rich veins of eastern Elba Island, northern Tyrrhenian Sea, Italy. / Mazzarini, Francesco; Musumeci, Giovanni; Cruden, Alexander.

    In: Journal of Structural Geology, Vol. 33, No. 10, 2011, p. 1509 - 1522.

    Research output: Contribution to journalArticleResearchpeer-review

    TY - JOUR

    T1 - Vein development during folding in the upper brittle crust: The case of tourmaline-rich veins of eastern Elba Island, northern Tyrrhenian Sea, Italy

    AU - Mazzarini, Francesco

    AU - Musumeci, Giovanni

    AU - Cruden, Alexander

    PY - 2011

    Y1 - 2011

    N2 - Detailed structural analysis of tourmaline-rich veins hosted in the contact aureole of the similar to 6 Ma Porto Azzurro granite in southeastern Elba Island, northern Tyrrhenian Sea is presented. Using geometric features of the veins, the physical conditions at the time of vein formation are estimated, namely the stress ratio (Phi = (sigma(2) - sigma(3))/(sigma(1) - sigma(3))), driving stress ratio (R = (P(f) - sigma(3))/(sigma(1) - sigma(3))) and fluid overpressure (Delta P(o) = P(f) - sigma(3)). Two vein sets (A veins and B veins) have been recognized based on orientation and thickness distributions and infilling material. Analysis of vein pole distributions indicates Phi = 0.57 and R = 0.24 for the A veins and Phi = 0.58 and R = 0.47 for the B veins, and fluid pressures less than the intermediate stress magnitude. Analysis of geometric features of the veins gives estimated fluid over-pressures of between similar to 16 MPa (A veins) and similar to 32 MPa (B veins). We propose a model for the tectonic environment of vein development, in which formation of secondary permeability in the deforming thermal aureole of the Porto Azzurro pluton was controlled by ongoing development of fracture systems in the hinge zone of a regional NNW-SSE trending fold that favored transport and localization of hydrothermal fluids.

    AB - Detailed structural analysis of tourmaline-rich veins hosted in the contact aureole of the similar to 6 Ma Porto Azzurro granite in southeastern Elba Island, northern Tyrrhenian Sea is presented. Using geometric features of the veins, the physical conditions at the time of vein formation are estimated, namely the stress ratio (Phi = (sigma(2) - sigma(3))/(sigma(1) - sigma(3))), driving stress ratio (R = (P(f) - sigma(3))/(sigma(1) - sigma(3))) and fluid overpressure (Delta P(o) = P(f) - sigma(3)). Two vein sets (A veins and B veins) have been recognized based on orientation and thickness distributions and infilling material. Analysis of vein pole distributions indicates Phi = 0.57 and R = 0.24 for the A veins and Phi = 0.58 and R = 0.47 for the B veins, and fluid pressures less than the intermediate stress magnitude. Analysis of geometric features of the veins gives estimated fluid over-pressures of between similar to 16 MPa (A veins) and similar to 32 MPa (B veins). We propose a model for the tectonic environment of vein development, in which formation of secondary permeability in the deforming thermal aureole of the Porto Azzurro pluton was controlled by ongoing development of fracture systems in the hinge zone of a regional NNW-SSE trending fold that favored transport and localization of hydrothermal fluids.

    UR - http://www.sciencedirect.com/science/article/pii/S0191814111001167

    U2 - 10.1016/j.jsg.2011.07.001

    DO - 10.1016/j.jsg.2011.07.001

    M3 - Article

    VL - 33

    SP - 1509

    EP - 1522

    JO - Journal of Structural Geology

    JF - Journal of Structural Geology

    SN - 0191-8141

    IS - 10

    ER -