Cu、Co、Ni、Ti和Mg在成岩型铁锰结核中的地球化学特征

GEOCHEMISTRY OF CU, CO, NI, TI,AND MG IN DIAGENETIC FERROMANGANESE NODULES

摘要: 选择了东太平洋赤道附近的系列成岩型铁锰结核(壳)样品,根据其中的矿物相的种类,利用化学上的相分析手段——选择性提取实验,借助晶体化学和矿物学手段对过渡金属元素Cu、Co、Ni、Ti和碱土金属元素Mg在成岩型铁锰结核中的地球化学特征进行了研究。结果显示,元素Cu、Co、Ni、Ti和Mg等元素在成岩型铁锰结核中的富集受这些元素在海水中的存在状态和结核中组成矿物这两方面因素的制约。成岩型结核中10Å-水锰矿结构的稳定性并不完全是由于其充分吸收了Cu、Co、Ni等过渡金属元素,碱土金属Mg对于10Å-水锰矿结构的稳定性起到了重要作用。

Abstract: A series of selective dissolution experiments were conducted on the diagenetic ferromanganese nodules from the East Pacific Ocean near the equator to study the geochemistry of Cu, Co, Ni, Ti,and Mg. Enrichments of the elements are controlled by the present states of the elements in the seawater and the compositional minerals of the ferromanganese deposits. The stability of the structure of 10Å-manganates in diagenetic nodules is attributed to the alkali earth element Mg in the structure besides the transitional metal elements Cu, Co and Ni incorporated into the structure that can stabilize the structure of 10Å-manganates.