Most studies of sandstone provenance involve modal analysis of framework grains using techniques that exclude the fine-grained breakdown products of labile mineral grains and rock fragments, usually termed secondary matrix or pseudomatrix. However, the data presented here demonstrate that, when the proportion of pseudomatrix in a sandstone exceeds 10%, standard petrographic analysis can lead to incorrect provenance interpretation. Petrographic schemes for provenance analysis such as QFL and QFR should not therefore be applied to sandstones containing more than 10% secondary matrix. Pseudomatrix is commonly abundant in sandstones, and this is therefore a problem for provenance analysis. The difficulty can be alleviated by the use of whole-rock chemistry in addition to petrographic analysis. Combination of chemical and point-count data permits the construction of normative compositions that approximate original framework grain compositions. Provenance analysis is also complicated in many cases by fundamental compositional alteration during weathering and transport. Many sandstones, particularly shallow marine deposits, have undergone vigorous reworking, which may destroy unstable mineral grains and rock fragments. In such cases it may not be possible to retrieve provenance information by either petrographic or chemical means. Because of this, pseudomatrix-rich sandstones should be routinely included in chemical-petrological provenance analysis. Because of the many factors, both pre- and post-depositional, that operate to increase the compositional maturity of sandstones, petrologic studies must include a complete inventory of matrix proportions, grain size and sorting parameters, and an assessment of depositional setting.

中文翻译：

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量化次生基质对砂岩成分分析的影响，以及一种岩石化学技术，用于检索蚀变砂岩的原始构架模式。

多数砂岩物源研究涉及框架颗粒的模态分析，使用的技术排除了不稳定的矿物颗粒和岩石碎片的细颗粒分解产物，通常称为次生基质或假基质。但是，这里提供的数据表明，当砂岩中的假矩阵比例超过10％时，标准岩相分析会导致对物源的错误解释。因此，不应将诸如QFL和QFR之类的岩相分析计划应用于次级基质含量超过10％的砂岩。假单胞菌普遍存在于砂岩中，因此这是种源分析的问题。除岩相分析外，还可以通过使用全岩石化学方法来缓解这一困难。化学和点数数据的组合允许构建近似原始框架颗粒成分的标准成分。在许多情况下，由于风化和运输过程中的基本成分变化，种源分析也很复杂。许多砂岩，特别是浅海沉积物，都经过了剧烈的修复，可能破坏不稳定的矿物颗粒和岩石碎片。在这种情况下，可能无法通过岩学或化学手段检索物产信息。因此，化学岩石物源分析应常规包括富含假基质的砂岩。由于沉积前和沉积后有许多因素会增加砂岩的成分成熟度，