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为查明粒度和分选作用对沉积物REE配分的影响．Crichton等（1993）对比了怀俄明州东南部年龄为2.0Ga的Libby溪群的石英岩、泥质岩和冰碛岩的成分，发现它们的REE型式相似（LREE富集，负Eu异常），相互间的成分差异大多可用石英的稀释作用解释。除少数元素（Ca、Sr、Ni和Cr）之外，Libby溪群和休伦超群Gowganda组冰碛岩的基质化学成分（包括REE）与新太古代上陆壳平均成分吻合较好，因此冰碛岩的主元素和微量元素都可反映上地壳平均成分。Libby溪群上部沉积物Eu异常程度增强．指示物源区Eu亏损程度增强和花岗岩突然增加，反映晚期有构造抬升。源区岩石可能是由玄武岩、花岗岩、TTG（英云闪长岩-奥长花岗岩-花岗闪长岩）所构成的混合模式。Libby这群下部的物源以TTG和玄武岩为主，上部物源以花岗岩为主。冰碛物的发育，Ca、Na、Sr和CIW（古风化指数）的变化等表明，随沉积时间的变新，古气候从相当寒冷，经温暖，变为最后的温热。铬云母石英岩的单矿物微量元素配分表明，铬云母含有全岩的绝大部分Th、U、REE、Sc、Co、Ni，并控制了全岩的REE配分型式。锆石含绝大部分Zr、Hf，其HREE含量在泥质岩中不足5％，在石英岩中不足20％。除锆、铪外，Libby溪群沉积物的多数微量元素主要集中在原始沉积可能为粘土矿?
To determine the effects of particle size and sorting on REE partitioning of sediments. Crichton et al. (1993) compared the composition of quartz, mudstone and moraine rocks in the Libby brooks of age 2.0 Ga in southeastern Wyoming and found that their REE patterns are similar (LREE enrichment, negative Eu anomalies) Most of the differences between the composition of quartz can be explained by the dilution effect. Except for a few elements (Ca, Sr, Ni and Cr), the matrix composition (including REE) of the Libby Creek Group and the Moraine of the Huron Gowganda Formation coincide well with the average composition of the Upper Archean upper continental shelf, The major elements and trace elements of moraine can reflect the upper crustal average composition. Eu anomalies in the upper Libic Creek sediments are enhanced. The increase of depletion of Eu in the indicator source area and the sudden increase of granite reflect tectonic uplift in the late stage. The source rocks may be a mixture of basalt, granite and TTG (English-type diorite-granite-granodiorite). The lower part of Libby is mainly composed of TTG and basalt, while the upper part is mainly granite. The development of moraines, changes of Ca, Na, Sr and CIW (Paleo-Weathering Index) show that the palaeoclimate changes from fairly cold and warm to the last warm as the sedimentary time changes. The single mineral trace elements of chrome mica quartzite indicate that chrome mica contains most of Th, U, REE, Sc, Co and Ni in the whole rock, and controls REE distribution type of the whole rock. Zircons, which contain most of Zr and Hf, have a HREE content of less than 5% in mudstone and less than 20% in quartzite. In addition to zirconium and hafnium, most of the trace elements in the Libby Creek sediments are mainly concentrated in the original sediments may be clay minerals?