The Comparison Research Between Quartz-vein And Alterated-rock Gold Deposit In Daduhe Jiucaiping And The Metallogenic Model

Dadu River gold mineralization belt Jiucaiping gold deposit located Xianshuihe Longmen Mountains Panxi rift with trigeminal intersection, belonging Presinian Kangding complex rock gold deposit, host rock of plagioclase amphibolite and granite diorite, the Dadu River in the Gold Zone quartz vein- one altered rock type gold deposits representatives. Deposit size small, with great prospects. In the course of geological work I found gold deposits in both Jiucaiping development has quartz vein type ore bodies, but also altered rock type ore bodies. According to preliminary observed both in the spatial distribution of the existence of the following relationships: deposit with a horizontal zoning, that is, along the main tectonic zone of mineralization with altered rock type mainly away from the main zone quartz vein structure based; orebodies have vertical zonation within quartz vein type gold deposit that is, outside the alteration type gold; zonation strike on that section of ore quartz vein type gold deposit, another section for the alteration type gold or to output a composite relationship. In order to clarify the two have similar metallogenic environment of their geological characteristics and ore mineralization process, and then discusses the intrinsic link between mineralization, put forward reasonable proposals for scientific exploration in the region, we selected Jiucaiping gold deposit for a detailed study to deposit.Through field investigation, indoor microscopic studies, ore and surrounding rock-forming elements testing analysis, host rock and quartz, pyrite and other trace elements in a single test and analysis of mineral ore sulfide sulfur isotope analysis, quartz ESR methods such as the deposit of comprehensive research system of mineralization with the objective Jiucaiping deposits in-depth understanding of:(1) Jiucaiping gold deposit ore mineral composition than those of simple metal minerals are mainly pyrite, gangue dominated by quartz mineral;(2) quartz vein and altered rock type gold mineralization is closely associated with pyrite, quartz and mineral REE patterns are consistent, it showed the gentle curve of rightist and have negative Eu anomaly, Ce extremely weak anomalous characteristics, indicate that the physical chemistry forming fluids Jiucaiping gold deposit formed may be relatively reducing environment, suggesting that the ore-forming fluids deposit may belong to the low-temperature hydrothermal fluids. On the other hand, quartz homogenization temperature range Jiucaiping considerable mineralization are concentrated in the 160 ℃ ~ 180 ℃, it belongs to the low-temperature hydrothermal fluid; to a lesser extent(3) Jiucaiping pyrite δ34S value change, δ34S value near 2.5, more stable composition and high degree of homogeneity, and the mantle is closer to forming fluids show characteristic sulfur having a mantle;(4) activation by quartz ESR dating methods, measured Jiucaiping gold deposit mineralization concentrated in the age of 17 ~ 13 Ma, which corresponds to the period after the collision of the Tibetan Plateau(25 ~ 0Ma), indicate that the main impact of shearing during orogenic type gold deposits formed after Jiucaiping gold deposit belongs;( 5) The two types of spatial distribution of mineralization and fracture properties are closely related, altered rock type is mainly controlled by a high level of fault a gentle inclination to pressure or compression-shear dominated, often produced in the main Fracture; quartz vein type mineralization is mainly controlled by the low-level fault steep dip in tensional or tenso based, often small-scale production in the secondary structure of the associated or derived. Different types of faults control the different types of gold, you can research on the characteristics of different types of gold deposits, the nature of ore controlling structure in further studies, in turn, can predict concealed ore controlling structure and possible occurrence of gold deposits.In summary, Jiucaiping quartz vein type gold deposit and altered rock ore belonging to the same cause, due to the different structural conditions and mineralization ways and produce different forms of ore. Times are consistent mineralization Himalayan mineralization temperature is low, by the ductile- brittle shear zone slipping control. After the deposit is on the eastern edge of the collision orogenic gold deposits formed late shearing, and in the middle with orogenic gold deposits.