Petrological Characteristics And Prospecting Prediction Of Alkali-Rich Porphyry In The Gold Deposit Of Baixiangchang,Binchuan,Yunnan Province

The study area is located in the alkali-rich porphyry zone of the western part of the Yangtze platform in China,and the ore-forming is controlled by the two faults of the Ailao Mountain fault and the Chenghai-Binchuan fault.The space is related to the Beiya gold deposit and MaChangqing Copper-molybdenum gold deposit and other porphyry deposits belong to a metallogenic belt,metallogenic geological conditions are superior.In this paper,Baixiangchang gold deposit is used as the research object,and the research work of field geological mapping,sampling,indoor rock and mineralization,electronic probe analysis,high precision test and zircon U-Pb dating are carried out for alkali-The petrological characteristics of the alkali-rich porphyry in the study area are studied systematically.The alkali-rich rock mass and its ore-bearing property are analyzed emphatically.The ore-rich rock mass is mineralized and the following is obtained:? The alkali-rich porphyry in the study area is shallow-ultramedous rock(rock vein,rock branch),and the rock type is dominated by two porphyry.Mineral composition with feldspar,plagioclase,amphibole and biotite and so on.? The Al-rich rocks in the study area are medium-acid rocks,which are characterized by SiO2 supersaturation,alkali-rich and high-potassium,high-aluminum and A-type granites.The aluminum saturation index A/NKC indicates that the porphyry belongs to the aluminum And the high ion lithophile elements such as Rb,Sr,Ba,Th,U,K are relatively enriched,and Ta,Nb,Ce,P,Ti are high The rare earth element meteorite standard distribution curve shows the light rare earth enrichment,heavy rare earth loss of the right smooth curve characteristics,which also has a weak europium negative anomalies.? According to the results of U-Pb isotope dating,we found that the 20 zircon measured at this time showed that the 206Pb/238U surface was in the range of 33.8?37.8Ma,but because of the "curtain lead loss",the harmonic curve It is concluded that the diagenetic age of the alkali-rich porphyry in the study area is 34.4 Ma,which belongs to the early Himalayan.? From the granite-type trace element tectonic environment discriminant diagram and the R1-R2 factor tectonic environment discriminant diagram show that the study area of alkali-rich porphyry produced in the post-collision tensile environment.The alkali-rich porphyry in the study area is derived from the mantle-derived crust-mantle mixing zone,which is the product of mantle-derived magmatic activity in the tectonic environment.? The alkali-rich porphyry in the study area is the ore-forming rock,containing gold,silver,copper,lead,zinc and other multi-metal mineralization.Based on the geological characteristics,petrological characteristics and geochemical exploration data of the study area,it is shown that the alkali-rich porphyry with white elephant has the favorable prospect of finding porphyry deposits.It is considered that there is great potential for finding large industrial porphyry deposits in the area of alkali-rich porphyry,the rock mass and the surrounding rock and soil,and the deep hidden porphyry body deserves further.