| 摘要: |
| 萨拉乌苏组作为中国北方晚更新世标准地层备受关注，但研究仍存争议。现有进展包括：明确马兰黄土与萨拉乌苏组的叠覆关系并细化地层划分；初步建立年代框架；实现千百年尺度高分辨率古气候重建，可关联全球沉积记录；系统整理古生物及人类化石产出层位与形态特征。争议问题在于：地层与区域或全球晚更新世对比存疑；缺乏基于新测年技术的精确年代标尺；气候代用指标物化机制不明；小型哺乳动物化石研究薄弱，化石-地层对应关系模糊，河套人的演化定位不清。未来研究需应用光释光测年技术，选择更可靠的气候代用指标，开展多维度系统研究以深化对萨拉乌苏组的认识。 |
| 关键词: 萨拉乌苏组 晚更新世 沉积时代 古气候 古生物 古人类 |
| DOI：10.7515/JEE231016 |
| CSTR：32259.14.JEE231016 |
| 分类号: |
| 基金项目:中国科学院战略性先导科技专项（B类）（Y92D070002）；中国科学院青年创新促进会会员项目（Y2022102）；第二次青藏高原综合科学考察研究（2019QZKK0901） |
| 英文基金项目:Strategy Priority Research Program of Chinese Academy of Sciences (Category B) (Y92D070002); Youth Innovation Promotion Association, Chinese Academy of Sciences (Y2022102); The Second Tibetan Plateau Scientific Expedition and Research Program (2019QZKK0901) |
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| A review of study on the Salawusu Formation: classic strata of the Late Pleistocene in northern China |
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ZHU Jingyu1, 2, 3, KANG Shugang1, WANG Xulong1*
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1. State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
2. University of Chinese Academy of Sciences, Beijing 100049, China
3. Xinpu Middle School, Lianyungang City, Jiangsu Province, Lianyungang 222000, China
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| Abstract: |
| Background, aim, and scope The Salawusu Formation, a classic Late Pleistocene sequence in northern China, has attracted considerable research attention. Nevertheless, significant controversies remain regarding its chronology, paleoclimate records, and paleoenvironmental significance. Synthesizing current knowledge of this formation is therefore of substantial academic importance. This study provides a systematic review of research progress on the Salawusu Formation, covering stratigraphic division, chronology, paleoclimatology, paleontology, and paleoanthropology, and outlines key directions for future investigation. Materials and methods We synthesize previous studies from the Salawusu area, with particular emphasis on research from the past decade, giving priority to advances in stratigraphy and chronology. Results Research conducted over recent decades has clarified several critical issues: (1) stratigraphic superposition relationships and refined subdivision of the Malan loess overlying the Salawusu Formation; (2) establishment of a preliminary chronological framework for the sequence; (3) development of high-resolution (millennial- to centennial-scale) paleoclimate reconstructions, enabling robust correlation with global records; (4) systematic documentation of the stratigraphic provenance and morphological characteristics of vertebrate and hominin fossils recovered from the formation. Discussion Accurate local stratigraphic characterization remains the fundamental basis of all research within the Salawusu River Basin. However, achieving consistent stratigraphic correlation across different parts of the basin remains challenging. Lacustrine deposits overlying the Chengchuan Formation exhibit at least four distinct initiation ages. Stratigraphic evidence suggests potential synchronicity between certain Holocene lacustrine and aeolian depositional events. This interpretation is supported by the presence of coarse-grained quartz particles with aeolian features within lacustrine sediments, raising questions about the reliability of facies-dependent paleoclimate proxies. The coexistence of contemporaneous aeolian and lacustrine facies further complicates paleoenvironmental interpretations. It challenges the traditional paradigm that equates aeolian deposition solely with arid conditions and lacustrine expansion exclusively with humid phases, thereby undermining the use of sedimentary facies as unambiguous climate indicators. Moreover, the spatial extent over which meaningful stratigraphic correlations can be drawn remains poorly constrained. For example, at Jiufangtai, immediately adjacent sections provide conflicting evidence: one indicates continuous deposition between the middle lacustrine unit of the Chengchuan Formation and the underlying aeolian sand, while the other one reveals a hiatus of approximately 80—90 ka between these units. Sedimentation rates also vary significantly across the basin. During marine isotope stage 2 (MIS 2), the sequence accumulated rapidly at the downstream Batuwan section, forming a 28-meter-thick deposit. In contrast, contemporaneous deposits at Dishaogouwan, Milanggouwan, and Jiufangtai each measure less than 10 m in thickness. Understanding the mechanisms behind such pronounced thickness variations over short distances requires further investigation. Conclusions Relying on a single section is insufficient to capture the full stratigraphic complexity and spatial variability of the Salawusu River Basin. Recommendations and perspectives Despite notable progress, several key challenges remain: (1) advanced luminescence dating techniques, such as recuperated OSL, and post-IR IRSL, are essential for constructing a more precise chronological framework; (2) a deeper understanding of the physicochemical mechanisms behind proxy indicators is needed to improve the accuracy of high-resolution paleoclimate reconstructions; (3) future work should emphasize systematic, fine-scale sampling at key sections to improve the collection and stratigraphic documentation of small mammal fossils; (4) clarifying the phylogenetic position of “Ordos Man” within human evolution will require integrating molecular evidence (where feasible) with existing morphological data. Future research on the Salawusu Formation must adopt integrated, multi-faceted, and systematic approaches to significantly advance our understanding of the basin’s paleoenvironmental evolution. |
| Key words: the Salawusu Formation Late Pleistocene chronology paleoclimate paleontology paleoanthropology |
