PARAGENESIS OF THE PAROO FAULT, MOUNT ISA, QUEENSLAND, AUSTRALIA
The first generation of quartz (Q1) is brightly luminescent and consists of angular to sub-rounded clasts (10-100μm), formed during early faulting. A subsequent deformation caused fracturing and rounding of Q1 clasts. Then a weekly luminescent generation of quartz (Q2) formed angular to sub rounded clasts around Q1. Cross cutting Q2 are fine (10-30µm) veins of moderately luminescent quartz (Q3) containing sulphide. Coarse carbonate (C1) and some sulphide mineralisation formed (in the fault) and were subsequently deformed. Q4 is luminescent quartz which forms large veins (300-1000μm) and is cross cut by the final stage of quartz (Q5) comprising small (1-5μm) brightly luminescent veins. C2 carbonates form along the edge of the large recrystalised quartz (Q1-5) grain boundaries in association with microfracturing and grain size reduction. C2 is associated with chlorite and carbonaceous material and is prevalent at the edges of the Paroo Fault. Reverse movement is recognized on the Paroo fault from macro-scale observations and from fluid inclusion plane (FIP) analysis. Normal movement is recognized from gouge marks on graphitic mylonite and quartz fish, drag structures, and the FIPs.