Study Of The Hydrothermal Alteration And Morphology Of Pyrite Of The Porphyry Gold Deposit In The Dongning Jinchang, Heilongjiang

The Jinchang gold deposit of Dongning is a large-scale deposit related to the Indosinian-Yan-shanian intermediate-acid volcanic-subvolcanic rock.The No.18 ore body is studied by this paper,and this ore body is suggested to be one of the mathematic dome rock type by Chen Jing-rong,controlled by the ring structure,so it should use the prospecting model of orthophyric tectonic altered rock-type.In this year, based on three drillings in the No.J-18 gold body, this paper studied on the hydrothermal alteration, magnetization and morphology of pyrite. Here are as follows:1,There are manily alteration of wall rock such as K-feldsparization, chloritization, pyritized-phyllite, silification, Kaolinization and carbonation. Silification and pyritized-phyllite are manly related with the gold mineralization.2,The decline sequence of the alteration magnetization is: chlori-tization- Kaolinization-silification.3,Feature of the different of the morphology of pyrite is :{100} habit crystals are developed in the early stages and {210} in the major.4,According to the study of the chemical typomorphic characteristic of pyrites,the pyrites lost S are in the ascendant;S replaced by As,Sb,Se and Te;Fe replaced by Co and Ni,and some of the Cu,Pb and Zn interfused in the pyrite.5,According to the study of the crystal structure typomorphic characteristic of pyrites, the lattice constant of the I and IV is high, and it match to the value of the As+Sb+Se+Te, but it is unusual that the the lattice constant of the early stages is high. It should be researched.6,According to the study of mineralizing characteristics and the alteration ,it suggested that the No.18 orebody is the type of the porphyry gold deposit,going with the orthophyric tectonic altered rock-type Using the mapping of the alteration , magnetization, morphology and chemical typomorphic of pyrite , Preliminary studies suggest that there are unknown rich ore segment under -400m deep .So the bottom of the drillings of ZK18-4 should be explored especially.