从西南硫矿带内黄铁矿生物组构论微生物成矿作用

西南硫矿带黄铁矿床主要产于二叠系龙潭组底部,硫铁矿的形成与峨眉山玄武岩喷发活动有一定关系,本文主要研究了区内生物结构黄铁矿的成因,认为生物组构莓状黄铁矿成因与生物菌群及微生物富集作用有关。研究表明,该区内的黄铁矿成矿作用主要由玄武岩海解而析出铁质与细菌还原硫酸盐及分解有机硫所产生的H₂S作用,形成黄铁矿,生物一方面直接参与了成硫,另一方面又间接参与了成矿作用。

On Biological Mineralization with Reference to the Biological Textures of the Pyrites from the Southwest Sulfide Zone

The pyrite deposits of the Southwest sulfide zone mainly develop at the bottom of the Permian Longtancoal-series,whivh to a certain extent,has velation with the eruption of the Emeishon Basalt. Investigationsof dcposits by the author paint out some biotrxture-marked pyrites and framF,oidal pyrites. Under SEM andEPA examinations,frambeidal aggcregate of pylite. enolosed within organisms is proved as a kind of from-boidal b.ma}ri.i while t,iotextures of pyrite are causcd by replacemrnt. On the basis of the above studies,theauthor, descrihes a close corrvelation betwcen the biotexturrs and the formation of the framboidal pyrite. Tospeak in detail,when basaltic erupted,flcwrd and reached sea basin, it decomposed right away in the pees-ence of sea water and separated into a great number of ferrugincus materials. These linked befwe long withthe H₂S produced through,reduction of sulfate and deconnposition, of ogranic sulfur,all,by bacterium.finally to form pyrite. In the course of later sedirnento-disgenesis,franrboidal sulfur bacteriom were adle to highly brced within buried organisms. In the meantime?if there existed a strongly reducing regime around the microorganisms,the S。 of their bodies would react with the nearby Fe2+HS- and FeS. This led not only ti.precipitation of framboidal pyrites also to perfect preservation of the biotextures which featured them. From the above explanation,one can easily concludes that the pyrite of the study area its mineralizationto the ferruginous influx related to decomposition of basalt by sea water and,what is more important,to ac-tivities of microorganisms and bacterium:one directly having a band in sulfur production and the other beingresponsible for sulfate reduction and,indirectly, for sulfur mineralization.