• The Korean Journal of Quaternary Research
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• v.1 no.1
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• pp.3-20
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• 1987

With regard to the Quaternary formations in the Korean Peninsula, very few studies have been done specially from a stratigraphic viewpoint. The alluvial sediments filling in the valleys have often been considered as the only formation of Quaternary age (more precisely of the Holocone) and so the Pleistocene was regarded as an erosional or nondepositional episode. This is apparently evident from a quick look at the general geological maps of the Peninsula, which show a lithological sequence of Mesozoic or Paleozoic substrata immediately overlain by Holocene alluvium. Likewise, the Pleistocene period was described in terms of unconformity in most local or regional stratigraphical successions of the Peninsula. Recently several different types of Quaternary formation, besides the so-called Holocene alluvium in the valley plain have been found around the Peninsula. They consist of coastal deposits, marine or fluviatile terrace deposits, ancient valley fill deposits or slope deposits. Some parts of the volcanic sediments in Jeju Is. are also known as the Quaternary sequence. Thus the Quaternary deposits in the Peninsula are far more developed than previously known to gelolgists. Moreover the importance of Quaternary research became recently apparent in Korea due to the shortage of raw materials and to the policy of an optimum land-use. Advanced constructions and land reclamation have required more precise engineering parameters of loose materials and an estimation of land stability. This does not imply only the engineering, or the structural properties of the loose material, but at the same time the basic study of the sediments from the stratigraphical and environmental viewpoints has been necessary. In this connection, Quaternary outcrops specially along the coastal fringe of the Peninsula have been mapped, profiled and sampled for sedimentological, clay-mineralogical and palaeomagnetic studies. All these results are compiled for the core of the Quaternary stratigraphy of the Peninsula.

• The Journal of the Petrological Society of Korea
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• v.9 no.1
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• pp.1-12
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• 2000

The Cretaceous basaltic rocks in Gyeongsang Basin are temporally and spatially dispersed widely in thick sedimentary piles: Chilgog basaltic rock (CGB) and Cheongyongsa basaltic rock (CSB) in the Shindong Group, and Hakbong basaltic rocks (HBB), Osibbong basalt (OSB), Secheondong basaltic rocks (SCB), Haman basaltic rocks (HAB), Hama basaltic rocks (HMB), and Chaeyaksan basaltic rocks (CYB) in the Hayang Group, upwardly in their stratigraphy. Chilgog basaltic rock is merely identified as pebbles in the Shilla Conglomerate and its provenance has not been found, and it is characteristics that the volcanics except Osibbong basalt and Chaeyaksan basaltic rocks are very small in both of their thickness and extension. Petrochemical diversity of the basaltic rocks are revealed; OSB and SCB distributed in the Yeongyang Minor Basin preserve the calc-alkaline natures in major and immobile minor element geochemistry, but CGB, HBB, HAB, and CYB reflect that they might be originated from calc-alkaline basaltic magma of volcanic arc in continental margin area by trace elements and altered to alkaline suites in the viewpoint of their major element geochemistry. Major and trace element geochemistry of CSB and HMB suggests that they may be derived from within -plate alkaline magma contaminated by the upper continental crust, especially in the case of the former.