• Title/Summary/Keyword: Jeongok basalt layer

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Stratigraphic Analysis on Paleofluvial Outcrop underJeongok Basalt Layer in the Chugaryeong Rift Valley, Central Korea (추가령 열곡 내 전곡 현무암층 하부 고하성층 노두 층서 분석)

  • Lee, Min-Boo;Lee, Gwang-Ryul
    • Journal of The Geomorphological Association of Korea
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    • v.20 no.3
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    • pp.55-63
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    • 2013
  • The study deals with the geochemical analyses on the stratigraphy and sedimentation of the paleofluvial outcrop under Jeongok basalt layer in Chugaryeong Rift Valley. The results of field survey and analysis show that the paleofluvial sand and gravel layers had been constructed before the arrival of basaltic lava in Jeongok area of Hantan River valley in central Korea. XRF, for the main elements analysis, results present that JG2-3, a test sample from basalt weathering layer, has different characteristics from 5 other samples in the aspects of chemical weathering levels. ICP-MS, for analysis of the rare earth elements analysis, estimates that gravel layer, in the lowest part of the outcrop, had been originated from pre-lava bedrocks near the upper reach of the Hantan River, so the layer is almost not related to basalt layers. Finally, the OSL dating results in paleofluvial sedimentation had been in process until nearly 40,000 BP, before formation of lava plateau in the Jeongok area.

Paleomagnetic and Soil Chemical Studies on the Quaternary Paleosol Around the Hantan River (한탄강 인근 제4기 고토양층에 대한 토양화학 및 고지자기학적 연구)

  • 김복철;황재하;이윤수;이규호;남욱현
    • Economic and Environmental Geology
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    • v.37 no.3
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    • pp.325-334
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    • 2004
  • Detail downward variation records for paleomagnetic, XRD, photospectrogram, TOC results were obtained from the soil developed along the Hantan River, Gungpyeong-ri, Cheongsan-myeon, Yeoncheon-gun Gyeonggi-do. The unconsoildated sediments underlain by the Jeongok Quaternary Basalt indicates that the paleosol formed twice with different ages, as apparently indicated by sedimentological, paleomagnatic, and soil chemical properties. The paleosols recorded paleoclimate and paleoenvironments of about 271.21$\pm$89.8 ka before eruption of the Quaternary Jeongok Basalt.