Year-end Sale % OFF 
Abstract
Mass wasting and landform modifying events have a profound impact on hydrothermal processes in terrestrial environments. Mass wasting events in submarine settings also modify hydrothermal systems and their associated mineralisation. We present evidence of a dynamic environment impacting on ore formation at the historically exploited Pb-Zn-(Ag) mineralisation of Triades, Milos island (Greece), formed in a submarine setting. Galena-sphalerite veins and barite-quartz gangue precipitated in the near subsurface or after exhalation of boiling hydrothermal fluids. Field evidence indicates that mineralisation was extensively reworked by debris flow events during formation. The mineral paragenetic sequence is consistent with a Pb-Zn-(Ag) massive sulphide system, and analogous to the early stages of a Kuroko-type deposit, but Triades lacks massive sulphide bodies. We suggest that mass wasting events literally truncated the developing mineral deposit as it formed on the seafloor, destroying massive sulphide bodies and limiting the development of the ore mineral assemblages. Mass wasting processes in volcanogenic massive sulphide systems are ore-destructive, with little opportunity for “telescoping”, unlike terrestrial equivalents. Shallow marine systems in terrains subject to mass wasting may have low preservation potential, or may be classified as epithermal-like vein systems rather than stockwork portions of massive sulphide deposits.
Highlights
In the terrestrial environment it is recognised that landscape processes can significantly affect mineral deposit evolution; sector collapse at the Luise volcano had a profound impact on the formation of the giant Ladolam epithermal gold deposit (Müller et al, 2002), and progressive paleosurface degradation plays a key role in telescoping hydrothermal ore deposits (Sillitoe, 1994)
Samples were analysed through optical microscopy, supplemented by major element microanalysis from the British Geological Survey’s FEI QUANTA 600 environmental scanning electron microscope, equipped with an Oxford Instruments INCA Energy 450 energy-dispersive X-ray microanalysis (EDXA) system, with an Oxford Instruments X-Max large area (50 mm2) Peltier-cooled silicon-drift detector (SSD)
Mineralisation at Triades has been limited by mass-wasting events in the shallow submarine environment
Summary
In the terrestrial environment it is recognised that landscape processes can significantly affect mineral deposit evolution; sector collapse at the Luise volcano had a profound impact on the formation of the giant Ladolam epithermal gold deposit (Müller et al, 2002), and progressive paleosurface degradation plays a key role in telescoping hydrothermal ore deposits (Sillitoe, 1994). The volcanic lithofacies of submarine and emergent volcanoes show that dome degradation, passive and explosive eruptions, and syn- and post-eruptive mass-wasting events dramatically alter the submarine landscape (Leat et al, 2010; Wright, 1996; Wright et al, 2008; Wright and Gamble, 1999), which in turn will significantly modify extant magmatic-hydrothermal and geothermal systems.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
