• Journal of the Korean earth science society
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• v.39 no.1
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• pp.23-45
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• 2018

Moderately diverse, but very abundant trace fossils are found from the Late Pleistocene deposits of Jeju Island, Korea. Vertical I-, Y- and U-shaped domichnia of annelids or decapods are, over 2500, extremely abundant, 3D network domichnia of callianassids are, over 200, very abundant, and small sinuous trails of nematode repichnia are, over 50, abundant in number. Horizontal trails attributable to polychaete or worm-like animals are, less than 50, common, but horizontal spreiten burrows, fish traces and crab trackways are, less than 10, rare in occurrence. Of these trace fossils, Taenidium barretti, Undichna britannica and Undichna unisulca represent the first record from the Pleistocene in Asia. Psilonichnus upsilon is the second record in Asia. Crab trackways probably produced by underwater punting gait of sideway walking crabs may represent the first record in the world. In addition, diverse and very abundant footprints of more than 500 hominids, more than 200 birds and more than 1000 mammals are closely associated with these invertebrate trace fossils. Trace fossil assemblage integrated with sedimentary facies is interpreted to have been formed in the marginal marine foreshore to backshore environment corresponding to the Psilonichnus and Skolithos ichnofacies.

• 한국석유지질학회:학술대회논문집
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• 2005.09a
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• pp.27-40
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• 2005

• The Korean Journal of Petroleum Geology
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• v.12 no.1
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• pp.34-42
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• 2006

Ichnology is the study of traces made by various organisms, which includes classification and description of traces, and interpretation of sedimentary process, behavior of organism and depositional environment based on traces and organism behavior. Ichnofacies, which is defined as the association of several traces related together with substrate characteristics and sedimentary processes, is closely related to depositional environment. Ichnology has been applied to sedimentology (to understand physical characteristics of depositional environment, sedimentation pattern and event bed), sequence stratigraphy (to recognize sequence boundaries and biostratigraphic discontinuities such as MFS, TSE and RSE), oil exploration (providing of many information without big cost) and palaeocology. Preliminary ichnological study on the Ganghwa intertidal flat shows that dominant ichofacies are changing with season and location, suggesting that their seasonal variation would be a good indicator to understand the seasonal change of sedimentary processes, the small- scale change of sedimentary environment and the preservation potential of such units. Ichnology on intertidal flat in western coast of Korea has a great potential to apply its results to petroleum geology as well as sedimentology.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.13-14
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• 2003

It is generally well known that Quaternary is characteristic geologically in terms of glacial and interglacial repeats and their associated unconformity formation. This paper deals with the first finding of the characteristic and significant meaningful unconformity between Holocene and late Pleistocene, which implies submergence and emergence of the tidal sedimentary basin along the western coastal zone of Korea during interglacial stage(IOS-5e) and glacial time(IOS-2). The stratigraphy of intertidal deposits in the Haenam Bay, western coast of Korea shows two depositional sequence units (Unit I of Holocene and Unit II of late Pleistocene) bounded by an erosional surface of disconformity. The disconformity is related to the latest Pleistocene sea-level lowstands (probably during the LGM). The Unit II is interpreted as intertidal deposit showing tidal sedimentary structures and crab burrow ichnology and has two parts (the upper part and the lower part) showing different lithology and character. The upper part of Unit II shows characteristic subaerial exposure features (emergence) and its related lithology. Such subaerially exposed upper part (more or less 4m to 5m in thickness) is characterized by yellow-brownish sediment color, cryoturbat-ed structure, crab burrow ichnofacies and high value of shear strength. Geochemical and clay mineral analyses of the upper part sediments also indicate subaerial exposure and weathering. In particular, very high value of magnetic susceptibility of the upper part in comparison to that of the lower part is interpreted as pedogenetic weathering during the subaerial exposure period.