东太平洋多金属结核中铁、锰元素的分形演化及其意义

The fractal evolution of iron and manganese of polymetallic nodules from the Pacific Ocean and its significance

运用分形理论,通过建立不同的相空间,计算了东太平洋多金属结核中的铁、锰元素的时间序列在各相空间中的关联分维,并与其在沉积物岩心中的关联分维进行了对比.通过研究发现,多金属结核中铁、锰元素和沉积物中Fe2O3及MnO在分形演化过程中均存在分维吸引子,认为沉积物中的Fe2O3和MnO可以用3个变量来描述,它们可能代表了火山、生物和陆地的三种来源,而描述结核中的铁、锰元素却需要14个变量,反映多金属结核中铁、锰元素的来源和/或赋存非常复杂,至少有14个因素在起作用,可能暗示了结核在形成过程中存在复杂的生物化学作用,为多金属结核的生物成因提供了间接的数学证据,同时也合理解释了结核生长结构所具有的自相似韵律现象.

The fractal evolution processes of geochemistrical series of the polymetallic nodule Sample 1783 are studied through computing their correlation dimensions in different embedding spaces. The results are compared with those obtained from the deep-sea sediment Core 1787. It is revealed that there are fractal attractors in the geochemistrical series of both the nodule and the sediment core,the Fe_2O_3 and MnO in sediment core can be described with 3 variables, which probably are volcanic,biogenic and terrestrial sources. However, it needs at least 14 variables to describe Fe and Mn in polymetallic nodules,which implies that the sources and/or existence of these elements in nodule are very complicated, at least 14 factors affecting, and complicated biochemical processes probably have taken place during the formation of nodules. So the studies of the fractal evolution of Fe and Mn in polymetallic nodules may provide indirect mathematic evidence for the biogenic origin of nodules,and also give the rhythmic micro-structure of nodules a reasonable explanation.