Jinchuan copper-nickel deposit characteristics of platinum group elements

Title: Jinchuan copper-nickel deposit characteristics of platinum group elements Author: Xu Gang Degree-granting units: Chang'an University Keywords: Jinchuan;; magmatic Ni-Cu-PGE sulfide deposits;; PGE;; ore causes Summary:

Jinchuan copper-nickel sulfide deposits in the deposit has a special status in recent years, many domestic and foreign geologists be a lot of research. In this paper, a systematic review and extract information based on previous geological, geology through field observation, systematic sampling, indoor light, thin, and identification of mineralogy petrology, Magnetic lifter geochemistry and PGE geochemical aspects of the research system , made the following main knowledge:

(1) Ⅰ, Ⅱ No. rock is similar to the PGE distribution pattern, with the major elements, rare earth elements and other geochemical characteristics of trace information displayed consistent, show that both have the same parent magma composition for the comagmatic evolution of the product.

(2) Jinchuan Ⅰ, Ⅱ No. rock rock and ore have similar PGE distribution patterns (Pt-Pd partition type), PPGE clear differentiation with IPGE to PPGE (Pt, Pd)-based, IPGE (Ir, Os, Ru, Rh) at low levels.

(3) PGE ore characteristics further evidence of the Jinchuan Cheng high-Mg magma tholeiitic magma. Deposits of rock and ore in Jinchuan Cu / Pd, Ni / Ir ratio (rock 42.59 × 103,7.87 × 105; ore 152.71 × 103,3.62 × 106) is much higher than the primitive mantle of Cu / Pd, Ni / Ir (7.7 × 103; 6.12 × 105) ratio (McDonough and Sun, 1995) These features indicate that the original magma in the magma chamber that existed before the invasion of a small amount of sulfide liquation. Initially obtained by further simulation about 0.013% of early onset pre-sulfide melt away.

(4) Major, trace rare earth and platinum group elements display the same characteristics of olivine, pyroxene and chromite in order to facilitate the magma fractional crystallization of sulfide melt saturation occurs from providing good conditions; partial http://www.999magnet.com/products/131-magnetic-lifter melting low level of Jinchuan copper-nickel deposit should not be reason for loss of PGE, and a small amount of sulfides from the pre-melting is caused by loss of the Jinchuan PGE magma main controlling factor.

(5) causes massive ore through simulation, that massive ore mainly from 10% to 40% fractional crystallization of MSS cooling after the formation of the consolidation, which with its relatively rich and poor PPGE IPGE characteristics consistent; rich Cu, Pt and Pd-rich massive ore and the special ore veins may be related to enrichment of solid solution crystals separated Cu, Pt and Pd in ​​the residual sulfide melt consolidation formation. Degree Year: 2010