Geochemistry of Quaternary sediments of the Jeongokri archaeological site, Korea: implications for provenance and palaeoenvironments during the Late Pleistocene

Abstract

The geochemical characteristics of an approximately 6‐m‐long sediment core collected from the Jeongokri archaeological site (Hantan River, Korea) were examined to determine the provenance of the sediments and to reconstruct the palaeoenvironment of the study area during the Late Pleistocene (200–127 ka). The core sediments were subdivided into two parts based on grain size: an upper (0–380 cm depth) and lower part (>380 cm depth). The lower part was deposited primarily by fluvial processes during an interglacial period [marine isotope stage (MIS) 7] with warm and humid conditions. Conversely, the upper part was mainly deposited by aeolian processes during a cold and dry glacial period (MIS 6). Geochemical characteristics, represented by major, trace and rare earth element (REE) compositions, and textures of the Jeongokri core sediments show distinct differences between the upper and lower parts. The mineralogy and major, trace and REE compositions indicate that the influence of felsic source rocks (e.g. granite) was dominant in the lower sediments, which were derived from the Hantan River. In contrast, increased quartz content and the very fine and homogeneous grain size in the upper sediments indicate an aeolian origin. REE ratios and distribution patterns, and geochemical signatures indicate that these sediments were derived predominantly from Chinese loess deposits and partially from local sediments from the Korean Peninsula; the possible source area of the upper sediments is the northern part of the Yellow Sea basin. The Yellow Sea basin, having mixed geochemical signatures between Chinese loess and Korean‐derived sediments, was exposed because of low sea levels during MIS 6. The exposed Yellow Sea basin was located in the path of winter‐monsoon winds, which may have carried a great deal of airborne sediments from the basin to the Jeongokri area. Copyright © 2011 John Wiley & Sons, Ltd.

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

“…The downhole variations in mean grain size, sorting and skewness of core E55S20IV-KNU2021 are consistent with lithostratigraphic units and previous studies near pit E55S20IV (Kim et al, 2012;Jeong et al, 2013) (Figure 3). Although the differences are very small, the grain size parameters in Unit I appear to show an increasing trend in mean grain size and more positive skewness, compared with those in Unit II.…”

“…Angular to subangular outlines with various reliefs were observed for all grains, and no rounded outlines were present (Figure 6). The The profile of mean grain size in this study was correlated with the mean size and median size data from previous studies in the Jeongok-ri area (light gray curves in the middle part of this figure) (Kim et al, 2012;Jeong et al, 2013). [Color figure can be viewed at wileyonlinelibrary.com] quartz grains commonly had very pristine angular edges in all directions, along with very weak edge abrasions (Figures 6A-F and 8).…”

“…Yi et al, 1983;Jian & Shannon, 2000;Keates, 2002;Corvinus, 2004;Lycett, 2007;Norton & Bae, 2008;Brumm, 2010;Bae et al, 2012;Lee, 2017). Separately, increasing geoarcheological interest in the Jeongok-ri site has been focused on both accurate depositional ages and transport agents of the artifact-bearing late Quaternary sediments, which are closely linked to the dates of hominin occupations and variations in paleoenvironmental conditions, respectively (Kim et al, 2012;Jeong et al, 2013;Yoo, 2014).…”

The Persistence of Mode 1 Technology in the Korean Late Paleolithic

“…The interpretation of soil wedges is under ongoing debate in Korea [23]–[28]. These structures are often observed in Korean Paleolithic sites [29]–[31]. Moreover, polygonal structures are also commonly observed; in lateral view, these features link up to the form of soil wedge.…”

Estimation of Origin of Tidal Land Soil using Rare Earth Elements

“…，人為的に付加されたトレーサとして物質移動・ 物質循環の研究 9, 10,11,12) に用いられたりしてきた．細泥 輸送に関しては，河床材料や海底泥の起源となる岩盤の 推定に関して国際的には地質学分野を中心に最近になっ ていくつかの試みが報告されている 13,14,15,16,17,18,19) 3. 調査結果…”