New discriminant-function-based multidimensional discrimination of mid-ocean ridge and oceanic plateau

作     者：Surendra P.Verma Lorena Diaz-Gonzalez Surendra P. Verma;Lorena Díaz-González

作者机构：Instituto de Energias RenovablesUniversidad Nacional Aut
onoma de M
exicoPriv.Xochicalco S/no.Col.CentroApartado Postal 34TemixcoMor62580Mexico Centro de Investigaci
on en CienciasUniversidad Aut
onoma de Estado de MorelosCuernavacaMorelos62209Mexico 

出 版 物：《Geoscience Frontiers》 (地学前缘（英文版）)

年 卷 期：2020年第11卷第5期

页      面：1681-1693页

核心收录：

学科分类：070704[理学-海洋地质] 0709[理学-地质学] 07[理学] 0707[理学-海洋科学] 

主　　题：MORB Multivariate discordant outliers Log-ratio transformation Multidimensional discrimination Analytical uncertainties Post-emplacement changes 

摘      要：From a compilation of geochemical data for the discrimination of the tectonic settings of mid-ocean ridge(MOR;3730 samples)and oceanic plateau(OP;3656 samples),we present two new discriminant functions and diagrams obtained from censored multivariate discordant outlier-free *** different sets of data(original concentrations as well as isometric log-ratio transformed(ilr)variables;all 10 major(M)elements as well as all 10 major and 6 trace elements MT)were used to evaluate the quality of discrimination from linear discriminant analysis(LDA)and canonical *** selected multidimensional models ilrM(9 ilr transformed variables of multi-normally distributed 10 major elements)and ilrMT(15 ilr transformed variables of multi-normally distributed combined 10 major and 6 trace elements),considered as the best or most representative(total of5650 samples for ilrM and 2858 for ilrMT),provided percent success values,respectively,of 80.9%for the MOR and 81.1%for the OP(ilrM)and 88.5%for the MOR and 90.1%for the OP(ilrMT).Both processes(log-ratio transformation and multi-normality)rendered the percent success values similar for both groups(MOR and OP).The respective discriminant functions were successfully used for four tests from known tectonic settings and four application cases(two for ophiolites and two for Precambrian rocks),documenting thus the utility of the new discrimination procedure for the MOR and OP tectonic ***,we showed that our multidimensional procedure is robust against analytical errors or uncertainties,as well as post-emplacement compositional changes caused by element mobility from both low or high temperature *** robustness against the gain or loss of a single element at a time was also documented,from which the ilrMT model was evaluated as more robust than the ilrM model.A new online computer program MOROPdisc was written in Java Framework ZK,which is freely available for use at our web portal http://***