Late Pleistocene sedimentary environment and reverse faulting along the Chugaryung Fault in the central Korean Peninsula: a case study on the Cheorwon Basin

Surface microtextures of quartz grains and minor sedimentary components across the Paleolithic Jeongok‐ri sediments, Yeoncheon, South Korea

“…Indeed, analyses of the SMQs of fine‐grained Jeongok‐ri sediments can provide opportunities to interpret the depositional environments, in contrast to evidence based on geochemical data that are related primarily to the ultimate provenance (Tucker, 1988; Mahaney, 1995; Itamiya et al, 2019; Wu et al, 2020). Because various controversies remain concerning the depositional environment of the upper Jeongok‐ri sediments (Shin et al, 2004; Kim et al, 2012; Bae et al, 2012; Jeong et al, 2013; Nahm, 2018; Shin et al, 2020), we focused on interpretation of these environments in the present study.…”

“…Although various depositional environments have been suggested for the upper part of the Jeongok‐ri sediments, recent interpretations have gradually coalesced around the notions of eolian sediments supplied from Asian dust or floodplain deposits closely related to the evolution of the Hantan River (Kim et al, 2012; Bae et al, 2012; Jeong et al, 2013; Nahm, 2018; Shin et al, 2020). This is because colluvial, marine and glacial environments are unrealistic for the current geographic and geological setting of the Jeongok‐ri site (Figure 1) (Jeong et al, 2013; Jo et al, 2014; Song et al, 2018).…”

“…The only widely mentioned sedimentary structures in the Jeongok‐ri sediments are several layers of ice wedge‐like structures. Unfortunately, current speculation regarding such structures has not been scientifically validated, although they have been observed in many locations on the Korean peninsula (Shin et al, 2004; Bae et al, 2012; Jeong et al, 2013; Shin et al, 2020). Furthermore, the sediments currently have problematic age constraints (Jeong et al, 2013).…”

“…The existing interpretations of depositional environments were mainly derived from geochemical and mineralogical data, especially in recent studies (Kim et al, 2012; Jeong et al, 2013; Shin et al, 2020). However, the previous studies provide valid data in terms of sediment provenances, rather than the transportation modes, reworking processes and ultimate depositional environment at the location of sedimentation.…”

“…In particular, the large area of the present Yellow Sea was exposed to eolian environments during each late Pleistocene glacial period. Although a few studies have mentioned ice wedge‐like sedimentary structures from many archeological sites on the Korean peninsula, including the Jeongok‐ri site (Shin et al, 2004; Jeong et al, 2013; Shin et al, 2020), the origins of these structures remain controversial (Bae et al, 2012). A layer including ice wedge‐like structures is commonly described in the wedge layer.…”