Analysis of chemical weathering trends across three compositional dimensions: applications to modern and ancient mafic-rock weathering profiles
نویسندگان
چکیده
Chemical weathering indices (one-dimensional/1D index values) and accompanying ternary plots (two-dimensional/2D compositional space) facilitate quantitative comparison of whole-rock mineral major-element data, empirical chemical trends with predicted vectors. However, data analysis in is restricted by poles grouping elements that are hosted different minerals or influenced selectively later alteration (e.g., diagenesis/metasomatism). Tetrahedral (three-dimensional/3D offer enhanced analytical utility shifting across four (or) incorporating additional proxy elements. space can better reveal combined effects on compositions from independent mineralogical controls post-depositional via curvilinear otherwise simplified linear space. This study focuses mafic-rock first reviews applications limitations the 1D mafic (MIA) lateritization/bauxitization (IOL/IOB) integrate into molar Al 2 O 3 –CaO * –Na O–K O–(FeO (T) /Fe 3(T) )–MgO SiO –Al –Fe space, respectively. Analysis tetrahedral then demonstrated Phanerozoic profile Precambrian paleosol two system (A–CN–K–FM AF–CN–K–M plots) one plot )–MgO–SiO (A–L–F–S plot). Common integrated these 3D spaces onto some their 2D faces. a key to (1) assessing integrative labile element loss while accounting for variable, redox-dependent behaviour Fe, (2) exposing, correcting for, overprinting diagenesis/metasomatism, (3) tracking Si all stages weathering.
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ژورنال
عنوان ژورنال: Canadian Journal of Earth Sciences
سال: 2022
ISSN: ['1480-3313', '0008-4077']
DOI: https://doi.org/10.1139/cjes-2022-0053