中文摘要：

通过对保德至克虎段不同地点砾石的岩性、粒径和产状的野外统计与测量,并对不同地点和不同阶地上砾石的岩性、粒径和产状进行对比,发现同一地区不同阶地砾石岩性具有很好的相似性,不同地区同一阶地砾石中灰岩砾石成分从上游向下游由主导成分变为次要成分,灰岩砾石粒径也从大变小,反映该区砾石为南北向古黄河冲积物。由于较老的一套砾石层为晚第三系红粘土所覆盖,说明黄河至少在晚第三纪已经在该区已形成。

英文摘要：

The lithology, grain size and orientation of the pebbles in different sites and on different river terraces have been studied along the Huanghe（Yellow） River from Baode to Kehu in the Shanxi-Shaanxi Gorge area. It is found that the pebbles are similar in lithology on different terraces in the same region, as well as on the same terrace from the upstream to the downstream. The grain sizes of limestone pebbles have a tendency of becoming smaller from upstream to downstream. This indicates the pebbles maybe the relics of the ancient Huanghe River. Because the highest pebbles are covered by late-Tertiary red clay, it is concluded that the Huanghe River run through this area at least in late Tertiary.