Abstract The article depicts the problem of river system development during the Middle Pleistocene Interglacial in the Bystrzyca River Valley (Sudetic Foreland, south-western Poland). Ten research sites located within the Świdnica Plain are presented, in which the structural, grain size (granulometry), petrographic, quartz grain morphoscopy, and heavy mineral analyses were carried out. The study results show the formation of piedmont fan deposits 2–8 km to the NE of the Sudetic Marginal Fault. The location of the fluvial deposits between the Sanian and Odranian tills indicates that they were deposited during the Holsteinian Interglacial (Krzczonów Formation, Mazovian; see Table 1). According toxthe lithofacies analysis, vast alluvial plains, composed of angular gravel grains in the south and of sands in the north, were deposited in the Sudetic Foreland in the environment of a very dynamic river. They are covered with a discontinuous layer of Odranian till. The petrographic spectrum shows 90–99% of local rocks, namely, Sudetic porphyry, Sowie Mts Gneiss and milky quartz, and 1–10% of Scandinavian rocks. In the proto-Bystrzyca river system, the existence of an oxbow lake in the distal part of the Krzczonów fan has been proved, which was developing at the end of the Holsteinian Interglacial. The continuity of the alluvial deposits is interrupted in the vicinity of Świdnica due to both the tectonic movements and the formation of the narrow tectonic graben of Roztoka–Mokrzeszów.

中文翻译：

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中更新世间冰期（Sudetic Foreland，波兰西南部）期间 Bystrzyca 河谷的演变

摘要 本文描述了 Bystrzyca 河流域（波兰西南部苏德蒂克前陆）中更新世间冰期河流系统发展的问题。介绍了位于 Świdnica 平原内的十个研究地点，其中进行了结构、粒度（粒度）、岩相学、石英颗粒形态学和重矿物分析。研究结果表明，在苏德蒂边缘断层的东北部 2-8 公里处形成了山前扇形沉积物。Sanian 和 Odranian 之间的河流沉积物的位置表明它们是在荷尔斯泰因间冰期（Krzczonów 组，Mazovian；见表 1）期间沉积的。根据岩相分析，南部为角砾石颗粒，北部为沙质的广阔冲积平原，沉积在苏德蒂克前陆的一条非常有活力的河流环境中。它们被一层不连续的 Odranian 覆盖。岩相光谱显示 90-99% 的当地岩石，即苏德蒂斑岩、索维山片麻岩和乳石英，以及 1-10% 的斯堪的纳维亚岩石。在原Bystrzyca河系中，已证实在荷尔斯泰因间冰期末期发育的Krzczonów扇末段存在牛轭湖。由于构造运动和 Roztoka-Mokrzeszów 狭窄构造地堑的形成，在 Świdnica 附近冲积沉积物的连续性被中断。Sudetic 斑岩、Sowie Mts 片麻岩和乳白色石英，以及 1-10% 的斯堪的纳维亚岩石。在原Bystrzyca河系中，已证实在荷尔斯泰因间冰期末期发育的Krzczonów扇末段存在牛轭湖。由于构造运动和 Roztoka-Mokrzeszów 狭窄构造地堑的形成，在 Świdnica 附近冲积沉积物的连续性被中断。Sudetic 斑岩、Sowie Mts 片麻岩和乳白色石英，以及 1-10% 的斯堪的纳维亚岩石。在原Bystrzyca河系中，已证实在荷尔斯泰因间冰期末期发育的Krzczonów扇末段存在牛轭湖。由于构造运动和 Roztoka-Mokrzeszów 狭窄构造地堑的形成，在 Świdnica 附近冲积沉积物的连续性被中断。