稳健丰度分析及丹池盆地上泥盆统元素丰度的意义

ROBUST ELEMENT ABUNDANCE ANALYSIS AND ELEMENT ABUNDANCE OF THE UPPER DEVONIAN STRATA IN NANDAN-HECHI BASIN, GUANGXI PROVINCE

稳健丰度分析方法是对传统均值法的改进,它弥补了后者不具稳健性这一缺陷。在处理元素分布总体分解时,引入了“混染模型”:F=(1—ε)H+εG。最后讨论了应用该法给出的丹池盆地主要含矿系D_3地层的微量元素丰度值的意义。

Robust element abundance analysis is introduced here to diminish non-robustness involved in traditional solutions, so that the results are not susceptible to the presence of outliers in observations, which is a general phenomenon in geochemical datum sets; otherwise, the calculat results may deviate from the real ones.This paper describes briefly some basic concepts of robust statistics, including breakpoint and influence function. And then a contamination model is constructed for geochemical data, i.e., the underlying distribution F of observed samples is supposed to be the combination of a main distribution H (for simplicity, which is usually selected as a normal one) and a contaminated one, G, orF = (1 - ε)H +εG.Finally, the paper gives out and discusses the element abundances in the Upper Devonian strata of the Nandan-Hechi Basin.