• Journal of the Korean earth science society
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• v.34 no.5
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• pp.381-392
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• 2013

Socheong island is a unique island containing Precambrian stromatolites in South Korea. Most of Socheong stromatolites are domes and columns, occurring as 10 cm to 1 m thick stromatolite beds. Lower parts of the stromatolite beds are predominantly composed of domes, but columns increase toward the upper level of stromatolite beds. In many of the stromatolite beds, inclined columns are easily identifiable, which is generally considered as a result of heliotropism. From general lithology, sedimentary structures, inclined angles and distributional pattern, and structural deformation of sedimentary rocks of Socheong island, the inclination of Socheong stromatolites could be better interpreted as a secondary structural deformation probably after formation of stromatolite columns, rather than as a result of heliotropism. However, at this moment, we do not clearly reject heliotropism interpretation for inclined columns of Socheong stromatolites. This is because the original position of stromatolite columns could have been lost if structural deformation had affected the whole sedimentary rocks of Socheong island.

• Journal of the Korean earth science society
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• v.28 no.1
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• pp.54-63
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• 2007

The sedimentary sequence of the non-marine Cretaceous Jinju Formation from Sacheon, Korea, contains a number of rod-shaped stromatolites (RSS) characterized by concentric lamination with curd-shaped, stratiform, and small columnar stromatolites. Unlike the world trend, a massive distribution of rod-shaped stomatolite was discovered in the region. The mineral composition, diagenetic alteration, and weathering process of the kind were analyzed by EPMA. The gross morphology of RSS is almost identical to broken plant twigs or stems formed by microbial activity onto which it grew. RSSs are interpreted as stromatolitic algae over plant twigs, which formed through concentric carbonate precipitation by epiphytic algal photosynthesis. The distribution of localities and horizons of the stromatolite imply that RSS is allochthonous and autochthonous. Two types of cyanobacterial filaments and one type of peen algal filament were discovered. The size frequency distribution of calcified filamentous microfossils found in stromatolite was $2.2{\mu}m\;and\;7.8{\mu}m$ in mean diameter of the former, $32.3{\mu}m$ in mean diameter of the latter. The cyanobacterial fossils played a key role in the formation of stromatolite, while the green algal filament was auxiliary stromatolite-builder stromatolites. The filamentous microfossils including trichome were found within the stromatolitic laminae.

• Journal of the Korean earth science society
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• v.31 no.1
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• pp.8-17
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• 2010

Geology and stromatolite fossil localities of Socheong Island are reviewed on the basis of previous studies and recent field survey. A new fossil locality of stromatolites which are very well preserved is recognized in Bunam area, northeast of Socheong Island. An outcrop composed of sandstone and shale alternations which exhibit well-developed laminations and folds is also found in the east of the Socheong harbor, and it is regarded as one of the symbolic features of the geology in Socheong Island. Stromatolite fossil localities of Socheong Island contains diverse and well-preserved Late Proterozoic stromatolites which are correlated with those from the Mukchon and Myoraksan series of the Sangwon System and diverse sedimentary structures such as ripple marks, desiccation cracks, and raindrop imprints. Stromatolites of Socheong Island, the oldest fossil Natural Monument of Korea, should be preserved at the national level, and continued intensive research must be conducted.

• 한국지구과학회:학술대회논문집
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• 2010.04a
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• pp.107-107
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• 2010

Geology and stromatolite fossil localities of Socheong Island are reviewed on the basis of previous studies and recent field survey. A new fossil locality of stromatolites which are very well preserved is recognized in Bunam area, northeast of Socheong Island. An outcrop composed of sandstone and shale alternations which exhibit well-developed laminations and folds is also found in the east of the Socheong harbor, and it is regarded as one of the symbolic features of the geology in Socheong Island. Stromatolite fossil localities of Socheong Island contains diverse and well-preserved Late Proterozoic stromatolites which are correlated with those from the Mukchon and Myoraksan series of the Sangwon System and diverse sedimentary structures such as ripple marks, desiccation cracks, and raindrop imprints. Stromatolites of Socheong Island, the oldest fossil Natural Monument of Korea, should be preserved at the national level, and continued intensive research must be conducted.

• Korean Journal of Heritage: History & Science
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• v.56 no.3
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• pp.214-232
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• 2023

Stromatolite at the Daegu Catholic University, Gyeongsan was designated as a natural monument in December 2009 because it was very excellent in terms of rarity, accessibility, preservation and scale. From the time of designation, the necessity of confirming the lateral extension of the stromatolite beds with the excavation of the surrounding area, and preparing a preservation plan was raised. Accordingly, the Cultural Heritage Administration conducted an investigation of the scale, production pattern, and weathering state of stromatolites with an excavation from April to December 2022, and based on this, suggested natural heritage values and conservation and use plans. The excavation was carried out in a 1,186m² area surrounding the exposed hemispherical stromatolite (approximately 30m2). Stromatolites are continuously distributed over the entire excavation area, and hemispherical stromatolites predominate in the eastern region, and the distribution and size of hemispherical domes tend to decrease toward the west. These characteristics are interpreted as a result of long-term growth in large-scale lakes, where stratiform or small columnar domes continued to grow and connect with each other, finally forming large domes. Consequently, large and small domes were distributed on the bedding plane in clusters like coral reefs. The growth of plants and lichens, as well as small-scale faults and joints developed on the stromatolite bedding surface, is the main cause of accelerated weathering. However, preservation treatment with chemicals as with dinosaur footprints or dinosaur egg fossil sites is not suitable due to the characteristics of stromatolites, and preservation with the installation of closed protection facilities should be considered. This excavation confirmed that the distribution, size and value of stromatolites are much larger and higher than at the time of designation as a natural monument. Therefore, additional excavation of areas by experts that could not be excavated due to the discovery of buried cultural properties (stone chamber tombs) and reexamination of the expansion designation of natural monuments are required.

• Journal of the Korean earth science society
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• v.35 no.5
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• pp.324-332
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• 2014

Many problems in naming natural monuments have been repeatedly argued by many researchers, and four different types of naming problems were identified: 1) name of unknown nationality (natural monument no. 82 and 108), 2) morphological name rather than scientific name (natural monument no. 180, 295, and 409), 3) name of fable character (local cultural property of Changnyeonggun), and 4) scientifically wrong name (natural monument no. 413). Among them, two cases (case 3 and 4) using wrong names are found in natural monument of geologic heritages, which should be ascribable to a hasty designation without an accurate and thorough scientific research. In order to solve these problems and to establish an ideal policy in designating natural monument, National Research Institute of Cultural Heritage has been carrying out a research project of "Pre-study and Post-designation (PSPD)", especially targeting the rod-shaped stromatolite. It is likely that this new strategy of PSPD is a unique and the first step to solve many problems in designating and naming geologic heritages as natural monuments. As a consequence, we strongly suggest that PSPD system must be applied to natural monument designation as an institutional arrangement.

• The Journal of the Petrological Society of Korea
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• v.24 no.4
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• pp.291-305
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• 2015

Microbialites are defined as rocks formed by microbial organisms. After their first appearance around 3.5 billion years ago, microbialites occur in various depositional environments throughout geological periods. Microbial organisms form microbialites by trapping and binding detrital sediments and/or precipitating carbonate cements, resulting in formation of various microstructures and mesostructures. Four major types of microbialites are distinguished based on their mesostructures: stromatolite, thrombolite, dendrolite, and leiolite. In the geological records, occurrences of microbialites are influenced by calcium carbonate saturation of seawater and interaction of microbialites with metazoans. Stromatolites mainly flourished during the Precambrian, and diminished as level of atmospheric carbon dioxide declined. On the other hand, thrombolites, mainly formed by calcified microbes, began to flourish from the Neoproterozoic. As metazoans diversified in the Phanerozoic, proportion of the microbialites within sedimentary record declined. Since then, microbialites only occasionally flourished during the Phanerozoic, such as shortly after mass-extinction events. In the Korean Peninsula, microbialites occur in the Neoproterozoic Sangwon System, the Early Paleozoic Joseon Supergroup, and the Cretaceous Gyeongsang Supergroup, which form different shapes according to their age and depositional environments. By performing detailed studies on these Korean microbialites, it is possible to understand how microbes affected geological records and sedimentary environments, as well as their interaction with other organisms.

• International Journal of Aeronautical and Space Sciences
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• v.15 no.4
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• pp.419-433
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• 2014

The Mars Exploration Rover Opportunity investigated plains at Meridiani Planum, where laminated sedimentary rocks are present. The Opportunity rover's Athena morphological investigation showed microstructures organized in intertwined filaments of microspherules: a texture we have also found on samples of terrestrial (biogenic) stromatolites and other microbialites. We performed a quantitative image analysis to compare images (n=45) of microbialites with the images (n=30) photographed by the rover (corresponding, approximately, to 25,000/15,000 microstructures). Contours were extracted and morphometric indexes were obtained: geometric and algorithmic complexities, entropy, tortuosity, minimum and maximum diameters. Terrestrial and Martian textures present a multifractal aspect. Mean values and confidence intervals from the Martian images overlapped perfectly with those from the terrestrial samples. The probability of this occurring by chance is $1/2^8$, less than p<0.004. Terrestrial abiogenic pseudostromatolites showed a simple fractal structure and different morphometric values from those of the terrestrial biogenic stromatolite images or Martian images with a less ordered texture (p<0.001). Our work shows the presumptive evidence of microbialites in the Martian outcroppings: i.e., the presence of unicellular life on the ancient Mars.

• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.366-375
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• 2017

Researching Stromatolites spread all over Gyeong-San, province Gyeongsangbukdo, it raise an objection for preservation of original state caused by natural weathering, artificial destruction, illegal emission and enviromental pollution. Stromatolites in Gyeong-San was formed on lake Meszoic era cretaceous. So it is representative rock of geological feature of sediment formed in water and landscape. It could be used as educational data on mesozoic stratum and earth surface, and resources of observation and experience program. It could apply as educational venue place in terms of Mesozoic era cretaceous motif. And it is managed various programs appling 4H (Healing, Hiking, Hand, History) experience program based on local community. And it is concerned software program introducing augumented reality, furthermore discuss with related field.