Discussion on the Characteristics and Metallogenic Mechanism of the Ductile Shear Zone in Laowan Gold Deposit,Henan Province
The Laowan ductile shear metamorphic zone is a part of the boundary structure between the North Qinling Paleozoic fold zone and the South Qinling Indosinian fold zone,distributed in an NWW direction and divided into four main strain zones and two strong foliated metamorphic zones.The lithology distribution within the zone is mainly composed of basic magmatic rocks,with some metamorphic rock blocks,acidic magmatic rocks,and rock veins.The gold mineralization is strictly controlled by the ductile shear metamorphic zone,mainly concentrated in the center of the RF4 strong strain domain and the Ⅱ strong schistosity zone on both sides.The diabase gabbro is the source layer of gold,and the later Laowan biotite granite plays a role in compositional transformation and strengthening circulation of gold bearing thermal fluids.The mineralization mechanism is complex.At the end of the Devonian,there was a collision between the northern and southern continents,with basic magma intrusion.Some Au was brought into the magma → Indosinian period,and strong ductile shear deformation and metamorphism occurred.Au elements were activated and migrated,enriched towards strong strain areas → Yanshan period.The addition of heat from the Laowan granite magma further led to the accumulation and mineralization of Au in the shear strong strain zone.
Ductile shear zone characteristicsMineralization mechanismgold depositLaowan
万方数据
维普
