• ALGAE
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• v.34 no.2
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• pp.91-97
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• 2019

Chilean species of marine macroalgae with amphitropical distributions oftentimes result from introductions out of the Northern Hemisphere. This possibility was investigated using haplotype data in an amphitropical red macroalgae present in Chile, Callophyllis variegata. Published sequence records from Canada and the United States were supplemented with new collections from Chile (April 2014-November 2015). Specimens of C. variegata were amplified for the 5′ end of the cytochrome c oxidase subunit I gene (COI-5P) and the full length nuclear internal transcribed spacer region. Haplotype networks and biogeographic distributions were used to infer whether C. variegata was introduced between hemispheres, and several population parameters were estimated using IMa2 analyses. C. variegata displayed a natural amphitropical distribution, with an isolation time of approximately 938 ka between hemispheres. It is hypothesized that contemporary populations of C. variegata were established from a refugial population during the late Pleistocene, and may have crossed the tropics via rafting on buoyant species of kelp or along deep-water refugia coincident with global cooling, representing a rare case of a non-human mediated amphitropical distribution.

• Korean Journal of Heritage: History & Science
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• v.35
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• pp.4-27
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• 2002

During the last 10 more years, more than one hundred of Paleolithic sites were found in the most part of the Korena peninsula by very active third generation of Paleolithic archaeologists. It became quite sure that most parts of the peninsula was populated during the late Pleistocene. High concentratin of Paleolithic sites in the Chollanamdo Province will be one of the most important field of paleolithic archaeology along with the sites in the Hantan -Imjin river basin. The begining of Upper Paleolithic is quite likley sometime earlier than 30,000 BP and possibly upto 40,000 BP. Micorlithic technology was probably introduced into the peninsula sometime around 20,000 BP. It is quite striking that the Acheulean-typed stone industry from the Chongokni site could be older than 350,000 BP that was estimated by sedimentation rate on the basis of the interval between two different types of Japanese tephras found at the site. More Acheulean-typed bifaces were found in some sites in the Hantan-Imjin river basin. Tanged point which originally found at the Suyanggae site were found at many Upper Paleolithic sites and was made until quite late period of Upper Paleolithic along with micro-blade.

• Journal of The Geomorphological Association of Korea
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• v.25 no.4
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• pp.49-62
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• 2018

This study tries to reveal uplift rates inferred from relative and absolute ages on coastal terrace in the West and South Coasts of South Korea. Uplift rate from relative ages on Pleistocene coastal terrace in the West Coast rangesfrom approximately 0.059 to 0.282 m/ky, while a range of approximately 0.020~0.385 m/ky is calculated from the South Coast, suggesting that the South Coast shows higher rate than the West Coast. Based on absolute ages on coastal terrace during MIS 5 in the South Coast, on the other hand, the uplift rates 1 and 4 have ranges of approximately 0.042~0.062 m/ky and 0.051~0.087 m/ky, respectively, indicating that uplift rate in the South Coast is one-third to one-fourth to that in the East Coast. No research on absolute ages in West Coast terrace and lack of relative and absolute ages in the West and South Coasts are considered as the limit in this study.

• Journal of The Geomorphological Association of Korea
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• v.27 no.2
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• pp.47-64
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• 2020

The Baengnyeongdo-island, located at the northernmost point of the west coast, has developed several coastal landforms. Although the coastal landforms of Baengnyeongdo-island are widely used as a tourism resource, a lot of academic research has not been conducted. In this study, particle size analysis, XRF, and OSL age dating were performed on the BR sandy deposits to find out the formation of coastal sand dunes on Baengnyeongdo-island. Based on the physicochemical properties, the BR section was divided into three parts; BR-A, BR-B and BR-C. First, about 56ka, which corresponds to the MIS 3, fine sand was deposited and forms the BR-C section. Second, the BR-B which located middle part of BR section, showed reversed age stratigraphy. The BR-B was interpreted as reworked sediments based on sedimentary facies and chemical weathering intensity. And, the BR-A composed of fine and medium sands was formed in middle Holocene. This research has significance in that it finds out the paleo sand dunes formed in Pleistocene. This study can contribute to understanding coastal sand dune development on the west coast.

• Animal Systematics, Evolution and Diversity
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• v.40 no.1
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• pp.47-67
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• 2024

The bryozoan assemblage from Seogwipo Formation in Jejudo yielded 33 taxa, including seven cyclostomes and 26 cheilostomes. It is the first fossil bryozoans described from the entire Korean peninsula. Five species, Callopora inermis, Tegella horrida, Celleporaria reflexa, Porella rotundirostris, and Rhynchozoon obliquimandibulatum, are new to the Korean bryozoan fauna as both in the Recent and fossil records. Tegella horrida, Celleporella reflexa, Porella donoghueorum, and Leischara subgracilis are notably cold-water species. This suggests that the Seogwipo Formation was primarily deposited in shallow water environment, subject to changesinfluenced by warm-water masses and temporarily impacted by cold currents. Only 33 species from the Seogwipo Formation in Korea, are very poor because the Seogwipo Formation is the only Pleistocene marine deposit in the Korean Peninsula. Eight species previously unknown as fossils worldwide, Tubulipora perforata, Puellina paracaesia, Reginella multipora, Celleporella reflexa, Exochella cryptodontia, Suhius cf. rubescentis, Cheiloporina cf. haddoni, and Jodoella koreensis are found in the Seogwipo Formation. This study is meaningful as it reports the first fossil assemblage of bryozoans from the Korean peninsula.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.311-321
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• 2009

Three categories (freshwater, amphidromous, and marine fishes) of Taiwanese fishes are analyzed on the basis of zoogeographic elements, viz. China element, Indo-China element, Indo-West Pacific element, Indo-Pacific element, North-Pacific element, Japan-Oregon element, and circumtropical element. Freshwater fishes, which include the China and Indo-China elements, are distributed on part of the boundary area between the Palaearctic and Oriental regions of Wallace (1876). Diadromous fishes include the North-Pacific, Indo-China and Indo-West Pacific elements. Taiwanese salmon, a landlocked (initially diadromous) species that became established in Taiwan between 0.5 my B.P. and the early Pleistocene, is recognized as a distinct taxon included within the Oncorhynchus masou complex, which comprises here three species and two subspecies, viz. Oncorhynchus masou masou (Sancheoneo, Songeo, Sakura-masu or Yamame), O. masou ishikawae (Satsuki-masu or Amago), O. sp. (Biwa-masu), and O. formosanus (Taiwanese salmon), based on molecular, morphological and biological studies. Marine fishes are discussed under the following headings, brackish-water fishes (fishes of brackish waters and seas adjacent to continental coastlines, North Pacific and Indo-West Pacific elements; fishes of brackish waters and seas primarily around islands, Indo-West Pacific element), reef fishes (fishes of inshore reefs along continental coastlines from 0 to ca.100 m depth, Indo-West Pacific element; fishes of inshore reefs primarily around islands from 0 to ca.100 m depth, Indo-West Pacific element; fishes of offshore reefs along continental shelf edges from ca.150 to 300 m depth, circumtropical and Indo-Pacific elements; fishes of offshore reefs primarily around islands from ca.150 to 300 m depth, Indo-Pacific element), demersal fishes (fishes on continental shelves shallower than ca.150 m depth, Indo-West Pacific and Japan-Oregon elements; fishes on edges and upper continental slopes from ca.150 m to 500 m depth, Indo-West Pacific, Indo-Pacific, and circumtropical elements; fishes on lower continental slopes to abyssal plains from ca.500 m to 6,000 m depth, circumtropical element and rarely Indo-Pacific element), pelagic fishes (epipelagic fishes from 0 to ca.150 m depth, Indo-West Pacific, Indo-Pacific or circumtropical elements; meso- and bathypelagic fishes from ca.150 to 3,000 m depth, circumtropical element). The distribution of Taiwanese marine fishes are influenced by the Kuroshio Current, low-salinity and low-temperature waters from mainland China, and sea-bottom topography.

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.33-42
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• 2004

In South Korea a Pedo-sedimentary Sequence(PS) indicating the Last Glacial Maximun(LGM) is typified y a brown to dark brown, relatively stiff paleosol layers formed by repetitive freezing and thawing processes which in turn left characteristi glossic textures in soil-solum, polygolnal structures with a flagipans, vertical soil wedges or freezing cracks, and horizontal foliations, As a pre-LGM sedimentary sequences (older than 25Ka), the Old Fluvial Sequence(OFS) overlain by the Slope Sedimentary Sequence(SS) are distributed commonly at the base level higher than 14-15m above present river-bed along the major river basin. After the LGM (ca. 18Ka), the Young Fluvial Sequence(YFS) appears at an altitude ascending order of sedimentary profiles. In this fluvial organic muds of Jangheungri site(Jinju), Sorori site(Cheonwon), and Youngsan estruarine rivermouth(Mokpo) were exemplified in order to interpret their formation ages and environments. As result of $^{14}C$ datings, the formation ages of te organic muds are Boelling to Alleroed (MIS-1). These organic muds were fomed in fluvial backswamp or local pond/bog in response to shifting fluvial system. On the basis of palynological production dominant with Abies/Picea-Betula and Ranunculaceae, Compositae, Cyperaceae, and Graminae, it was interpreted that more boreal to subboreal condition was prevailed rather than temperate like today during the formation of organic muds and soil moisture condition was a repetition of wet and dry condition.

• Journal of the korean society of oceanography
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• v.39 no.1
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• pp.96-106
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• 2004

A total of 116 surface sediment samples were obtained on the Yellow Sea and analyzed for grain size and geochemical elements in order to interpret the present sediment transportation. Thirty-nine cores and 3,070 line-km shallow seismic profiles are analyzed for sedimentary records of Yellow Sea in the past. Results show that the boundary of sediment transport between Korean side and Chinese side is about between $123^{\circ}E$ and $124^{\circ}E$. The similar result is produced from Shi et al. (in this publication). Two cyclonic patterns of surface sediments are recognized in the northeastern and southwestern Yellow Sea, while the strong front zone of the mud patch and sandy sediments are found in the southeastern Yellow Sea (the southwestern part of Korean coasts). The formation of fine-particle sediment packages, called for Northwest Mudbelt Deposit (NWMD), Hucksan Mudbelt Deposit (HSMD) and Jeju Mudbelt Deposit (JJMD), are resulted from eddies (gyres) of water circulations in the Yellow Sea. NWMD has been formed by cyclonic (anticlockwise) eddy. NWMD is composed of thick, homogeneous, relatively semi-consolidated gray clay-dominated deposit. On the other hand, HSMD and JJMD are formed by anticyclonic (clockwise) eddies. They are thick, homogeneous, organic-rich gray, silt-dominated deposit. Both core and surface sediments show that the middle zone across Chinese and Korean side contains bimodal frequency of grain-size distribution, indicating that two different transport mechanisms exist. These mud packages are surrounded by sand deposits from both Korea and China seas, indicating that Yellow Sea, which is the shallow sea and epicontinental shelf, is formed mostly by sand deposits including relict sands. The seismic profiles show such as small erosional/non-depositional channels, sand-ridges and sand-waves, Pleistocene-channelfilled deposits, a series of channels in the N-S major channel system, and thick Holocene sediment package, indicating that more complex sedimentary history exists in the Yellow Sea.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.169-170
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• 2003

The existence of coastal terraces, HH(High higher) surfaces found at Gampo of southeast coast and at Jeongdongjin of the central east coast were confirmed at Jigyeong-Ri, the areal border between Gyeongju- and Ulsan city on the southeast coast of Korea Peninsula. Especially this study reports HH JK-surface located on the 155m a.s.l., which is the highest altitude among the ancient shorelines of the coastal terraces in Korea. The HH surfaces on the study area are classified into HH JK at 155m, HH-I at 140m and HH-II at 115m, and each formation stage is related to MIS 17(720∼690ka BP), MIS 15(630∼560ka BP) and MIS 13(510∼480ka BP) respectively. The HH-surfaces remain to be larger than those of H- and L-surfaces. The reason is caused by the unique factors of the coastal geology and morphology on the study area during the formation stage. And also the areal difference by the magnitude of upheaval doesn't exist from north to south because the altitude system of ancient shoreline on each coastal terrace is same along the east coast. The upheaval rate of the eastern coastal areas was measured in the relation to the ancient shoreline and formation stage among the coastal terraces such as HH JK-, HH-I, HH-II, H-III and H-IY surface, and was almost same as 0.23mm/y.

• Journal of the Korean association of regional geographers
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• v.10 no.1
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• pp.206-214
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• 2004

The purpose of this paper is to elucidate the formation process of the Second Mujechi Moor at Mt. Jeongjok. For doing so, 1 analysed the formation process of valley which moor is located in, and the formation process of block field damming the valley: First, it is not a valley but a hollow which the Second Mujechi Moor located in. Hollow was formed as weathering bedrock weathered deeply along joints under warm and wet climatic conditions was denudated by rain wash. Second, the Second Mujechi Moor had been a marginal lake. Block stream developed during the last glacial period of Pleistocene, and it dammed the mouth of hollow. Afterwards sediments transported from slope filled the marginal lake, thus the lake changed to the moor where aquatic plants could grown. Third, the Second Mujechi Moor is drained and dried out by removal of matrix material from the block stream dam of the mouth of moor. For keeping moor's present conditions, we must control moor's drainage by filling open space in block stream with fine material.