磷块岩形成过程中的生物作用

MICROBIOLOGICAL PROCESSES IN GENESIS OF PHOSPHORITE DEPOSITS

对我国震旦纪、寒武纪磷块岩矿床的研究表明，参与成磷作用的生物主要是菌、藻类微生物。生物作用的标志表现为：Ｐ２Ｏ５主要富集在叠层石磷块岩中，富集在叠层石的柱体上，富集在柱体内部的富藻纹层中；而与磷块岩共生的白云石和黄铁矿的δ１３Ｃ值和δ３４Ｓ值相对均较低，则是生物参与成磷作用的同位素标志特点。生物的成磷作用贯穿成磷过程的始终，但它随作用的相带、环境和阶段不同，生物的种属和作用方式也不同，因而矿石和矿床的质量也随之而异。

Having studied the industrial phosphorite deposits of Sinian and Cambrian in East China, we find that the biogenic mineralizational marke are striking. For example: the microorganisms in formation of phosphorite are principal baterium and algae; among all phosphorite types, the P2O5 contens enriched principal in the stromatolite phosphorite, enriched in the colurmn of phosphatic stromatolite, and enriched in the algae lamination of phosphatic stromatolite column; the δ13C and δ34S valuses in dolomite and pyrite paragenesis with phosphorite are usual lower, they are isotop marks that microorganisms take part in formation of phosphorites. Microbiological effects on formation of phosphorite continue through all process, and, the types of microorganism and thier process way are depened on the difference of metallogenic factes belts, environment and process stage. So, the tenors of ore bed are difference too.