磷块岩研究进展与磷块岩生物成矿说

近十年来,我国磷块岩的研究以沉积学的发展为先导,取得了长足进展。十年迈出两大步:第一步是由化学沉积说向物理富集成矿说的转变;第二步是生物成矿说的发展。业已在我国南方晚震旦-早寒武世各主要工业矿床的磷块岩中发现了大量多种形态的原核生物的细菌到真核生物的真菌等磷质微生物以及藻类和小壳动物化石(后者产于早寒武世磷矿中),它们是构成磷块岩的主要组分。磷块岩实际是一种特殊的生物岩。本文论述了磷块岩的生物成矿作用、生物聚磷机理,并从磷块岩岩石的生物特点、化学成分的生物特点、红外吸收光谱以及稀土元素组成的生物特点等方面,论述了磷块岩的生物成因。同时阐述了磷质生物繁衍的环境条件与磷块岩形成环境之间的内在联系,以及磷质生物的最佳繁衍场所与磷块岩成矿古地理单元的一致性,这种“生物繁衍场”与成磷古地理单元可称之谓“陆缘坻”。

Progress of the Phosphorite Research and Its Theory of Biomineralization

The research of sedimentary minerals produced in China has achievablely progressed for the recent dec-a.le or the basis of the sedimentary development, especially the phosphorite research has got abrrakthrough progress. The phoshhorite research has made two steps in a decade: the first is from the chem-tcalsedimentary theory to the physical enrichmentary nne and the second is the development of the biomineralization theory. Upper Sinian Epoch to the early period of Lower Cumhri}n Epoch is an unprecedented prosperous per:-od of the phosphorus microorganism and it is also the most important phosphorus mineralization one inChina, and tens of billion tons of phosphorus ore were formed. Many phosphorus microorganisms, suchas agla.and small shell fossils (the latter one is only produced in ore of Lower Cambrian) with variuusshapes have been found in phosphorites of every industrial mineral deposit and they are the main componentsof phosphorite. Among them the phosphorus microorganism is mainly f}ronu bacteria of procarytes to fungusof euearyotes. Up till now, three communities have been found, i.e., bacteria, actinomyces and mould.The author adopted microbiology, biochemistry and medicine to the piiosphorite research and discussed thephosphorite biomineralization, biological enrichment phospl;orus mechanism about tW oxidizingphosphoric acidification and biological calicification as will as expound the phosphorite biological cause onthe basris of the phosphorite petro-biological characteristics. The biological characteristics of the chemicalcomponents and the infrared absorptive spectrum, and the rare-earth element compositions and so on areanalysed, Phosphorite is actually a special biological rock and the phosphate composition ranges fromultramicros 0.05 }m-0.5}m to macroscopic particles front silt to medu}n sand. The phosphorite is consisted of single species bacteria and bacteria groupe, which consists of the same species microorganism and themicroorganism commuwties, which consist of the different species microorganism (including alga) as well as the small fossil shells. The phosphorite petro-types can be subdivided as micro-phosphorite. cumtila,rspharolith. coated granule. algal bacterium granule, strumutolithic, agglumerative. oncolitrsand small shell phosphorite.Organic chemical compound of life organizauon, such as remaining amino acid and nucleic acid etc., are commonly discovered by the analysis of organic chemical cumposition. On the ba sis of analysis of infrared spectrum there are organic pigments,-CH₃,-CH₂,-C=H₂OH and the vibration frequency of phosphorite is similar to one of the bone apatite of dinosauria, tortoiseand so on. The rare-earth elemetn standardization match model of the every phosphorite closesmodel of apatite with the typical biological cause from Palaeozoic Era to modern times.and hyolithto the match Mficroorganism is culsely related to circumstance tii multiplying circumstance condition ofmicroorganism relates internally to tile sedimentary circumstance of phosphorite. There are a lot of physicaland chemical conditions that influence the growing of microorganism, the important faotors aretemperature, Eh, pH and light. These most suitable conditions of.he microorganism breeding and grow-ing are closely related to the conditions of phosphorite forming. T'he 0biological breeding field" of the most suitable phosphorus biological growing and multiplying inocean shows no different from the palaeogeograpitical unit of the phusphorite mineralization. We call the bio-logical breeding field as“the epicontinental subqueous galley wall" which is the most favourableminerogenetic belt of phosphorite. Our research has discovered the two main industrial mineral layea ofDoushantuo period along the epicontinental subqueous galley wall which distribute from the western Hubeito the; middle Gui::hou offer as the regular overlap migration sediment according to the ingression and seacurrent directions. This law may be an universal one, otherwise, the two industrial mineral layers in theeastern Yunnan during Lower Cambrian Epoch offer also as the regular migration seiiiment according to theingression and sea current directions. This law can be used to survey and research for minerals.