(U+Th)/Ne dating of hematite from Leadhills-Wanlockhead Pb-Zn ore deposit: new insight into Triassic-Jurassic basin-to-basement ore-forming processes

摘要

Epigenetic hydrothermal Pb-Zn ore deposits are widespread across W. Europe (Gleeson and Yardley 2002). Many share common characteristics: extensional fault-controlled vein mineralisation; hosted by Palaeozoic-Mesozoic basins and/or adjacent basement; S and metals predominantly sourced from the basement; low temperature (<120-200°C) moderate to high salinity (10-30 wt. % NaCl+CaCl_2) mineralising fluids of meteoric origin; deep convective basin-to-basement hydrothermal fluid circulation model for ore-forming processes (Samson and Banks 1988; Halliday and Mitchell 1984; Cann and Banks 2001; Gleeson et al 2001; Munoz et al 1994). However, the timing of ore precipitation is largely unknown and has hindered our understanding the key ore-forming processes and means we have no strong tectonic framework.