• Title/Summary/Keyword: 대동식물군

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Diversity of Fossil Woods from the Korean Peninsula (한반도에서 산출된 화석목재의 다양성)

  • Kim, Jong-Heon
    • Journal of the Korean earth science society
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    • v.36 no.1
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    • pp.51-58
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    • 2015
  • In order to understand the broad outline and palaeobotanical significances, the fossil woods from the Korean Peninsula were integrated through the literature surveys. Types and diversity of them are gradually increasing from Mesozoic to Cenozoic, especially increased sharply in Cenozoic. During the Early Mesozoic, six conifer taxa belonging to four genera were described, which corresponds to about 6% of the Daedong flora. Those of the Late Mesozoic are all conifers, consisting of fifteen taxa belonging to seven genera, which corresponds to about 29% of the Nakdong flora. During the Neogene, thirty four taxa belong to sixteen families were described. Those woods mostly consist of dicotyledon and have the greatest diversity compared to other geologic eras, which corresponds to about 83% of the Janggi flora. It is inferred that such a rapid increase of the silicified wood fossils in Neogene are due to the abundant presence of dicotyledon in floral composition and of pyroclastic rocks in strata, which are appropriate for preserving wood as fossils.

Organ Fossils of Neocalamites carrerei from the Amisan Formation of the Nampo Group, Korea (남포층군 아미산층에서 산출된 Neocalamites carrerei의 기관화석)

  • Kim, Jong-Heon;Roh, Heon-Sun
    • Journal of the Korean earth science society
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    • v.29 no.6
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    • pp.466-473
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    • 2008
  • This study deals with the morphological characteristics and structure of organ fossils of Neocalamites carrerei such as rhizomes, aerial leafy stems, and cones collected in situ from the Amisan Formation of Nampo Group. Judging from the size of some extant Equisetum and paleoclimate of Daedong flora, it is considered that the size of Neocalamites carrerei was probably very large. The cone of Neocalamites takahashii (Kon'no) is closely associated with the leaves of Neocalamites carrerei. It indicates that two organ fossils mentioned above probably belong to the same species. Comparing with very abundant occurrence of aerial leafy stems and rhizomes in the Amisan Formation, cones are very rare. This fact implies that Neocalamites reproduce not only by spore reproduction, but also by asexual reproduction. Neocalamites largely differ in the leaf form and size from Equisetum.