https://repository.kopri.re.kr/handle/201206/5487 2026-04-23T10:44:31Z 2026-04-23T10:44:31Z Lee, Yong Il Lim, Hyoun Soo Lee, Min Kyung Yoon, Ho Il Choi, Jeong Heon Lee, Jae Il https://repository.kopri.re.kr/handle/201206/6168 2022-03-24T07:11:29Z 2011-01-01T00:00:00Z

Title: Comparison of radiocarbon and OSL dating methods for a Late Quaternary sediment core from Lake Ulaan, Mongolia Authors: Lee, Yong Il; Lim, Hyoun Soo; Lee, Min Kyung; Yoon, Ho Il; Choi, Jeong Heon; Lee, Jae Il Abstract: Both radiocarbon and optically stimulated luminescence (OSL) dating methods were applied to test their suitability for establishing a chronology of arid-zone lacustrine sediments using a 5.88-m-long core drilled from Lake Ulaan, southern Mongolia. Although the radiocarbon and OSL ages agree in some samples, the radiocarbon ages are older than the corresponding OSL ages at the 550-cm depth horizon (late Pleistocene) and in the 100？300-cm interval (early to late Holocene). In the early to late Holocene, radiocarbon ages are consistently older than OSL ages by 4,100？5,800 years, and in the late Pleistocene by 2,700？3,000 years. Grain-size analysis of early to late Holocene sediments and one late Pleistocene sediment sample (550-cm depth) indicates that eolian processes were the dominant sediment-transport mechanism. Also, two late Pleistocene sediments samples (from 400- to 500-cm depths) are interpreted to have been deposited by both eolian and glaciofluvial processes. Accordingly, the radiocarbon ages that were older than the corresponding OSL ages during the Holocene seem to have been a consequence of the influx of 14C-deficient carbon delivered from adjacent soils and Paleozoic carbonate rocks by the westerly winds, a process that is also active today. In addition to the input of old reworked carbon by eolian processes, the late Pleistocene sediments were also influenced by old carbon delivered by deglacial meltwater. The results of this study suggest that when eolian sediment transport is suspected, especially in lakes of arid environments, the OSL dating method is superior to the radiocarbon dating method, as it eliminates a common 'old-carbon' error problem.

2011-01-01T00:00:00Z Kim, Jeong Yul Kim, Cheong-Bin Lim, Hyoun Soo Kim, Kyung Soo https://repository.kopri.re.kr/handle/201206/6074 2022-03-24T07:11:19Z 2010-01-01T00:00:00Z

Title: New age constraints for hominid footprints found on Jeju Island, South Korea Authors: Kim, Jeong Yul; Kim, Cheong-Bin; Lim, Hyoun Soo; Kim, Kyung Soo Abstract: In 2004 numerous hominid footprints, along with diverse animal footprints, were found in the Late Quaternary strata of Jeju Island, South Korea. However, the age of the sediments in which the footprints were found is still controversial. Previous age estimates included radiocarbon ages of ca. 15,000 yr BP (Late Pleistocene) and quartz optically stimulated luminescence ages of ca. 7000 yr BP (mid-Holocene). In this study we report on 11 AMS 14C dating results from a new set of samples collected from the footprint-bearing strata and from associated sediments. Despite some variations and age reversal, all samples collected from the footprint-bearing strata yielded 14C ages of late Pleistocene. These ages are comparable with previous radiocarbon dating results. Furthermore, the presence of the proboscidean footprints attributable to woolly mammoths in the footprint-bearing strata supports the radiocarbon dating results. Based on the new radiocarbon dates and the presence of the alleged mammoth footprints, the age of the hominid footprints found at Jeju Island is thought to be late Pleistocene (about 19,000e25,000 cal yr BP). Therefore, this is the second discovery of hominid footprints dated to the Pleistocene age in Asia, and the first to be discovered in Korea.

2010-01-01T00:00:00Z Kota Katsuki Boo-Keun Khim Takuya Itaki Yoon, Ho Il Kang, Cheon Yoon Yuna Shin Ken Ikehara Yusuke Okazaki https://repository.kopri.re.kr/handle/201206/6268 2022-03-24T07:13:55Z 2010-01-01T00:00:00Z

Title: Sea-ice distribution and atmospheric pressure patterns in southwestern Okhotsk Sea since the Last Glacial Maximum Authors: Kota Katsuki; Boo-Keun Khim; Takuya Itaki; Yoon, Ho Il; Kang, Cheon Yoon; Yuna Shin; Ken Ikehara; Yusuke Okazaki Abstract: Sea-ice diatom taxa (Fragilariopsis cylindrus and Fragilariopsis oceanica) and their relative abundance in the Okhotsk Sea were used to reconstruct the history of sea-ice distribution and atmospheric pressure patterns since the Last Glacial Maximum (LGM). The temporal state of sea-ice distribution and atmospheric pressure patterns since the LGM can be divided into three modes: northern Aleutian Low mode, southern Aleutian Low mode, and strong Siberian High mode. The Southern Aleutian Low mode was dominant before 15 ka and after 6.5 ka, respectively, showing expanded sea-ice distribution into the central and southern Okhotsk Sea. During the deglaciation period (15 ka to 10 ka), sea-ice retreated from the southern Okhotsk Sea because of the pronounced westerly winds under the strong Siberian High mode. However, sea-ice distribution expanded in the northern Okhotsk Sea, which favors the development of extensive polynyas on the northern continental shelf. Occurrences of northern Aleutian Low mode were frequent between 10 and 6.5 ka, while sea-ice distribution expanded into the eastern Okhotsk Sea. Formation of the Okhotsk Sea Intermediate Water, inferred from radiolarian species Cycladophora davisiana, intensified under both northern Aleutian Low mode and strong Siberian High mode.

2010-01-01T00:00:00Z Lim, Hyoun Soo Yoon, Ho Il Chung, Chull Hwan https://repository.kopri.re.kr/handle/201206/6566 2022-03-24T07:14:01Z 2010-01-01T00:00:00Z

Title: Late Pleistocene Paleovegetation and Paleoclimate of the Uiwang Area Based on Pollen Analysis Authors: Lim, Hyoun Soo; Yoon, Ho Il; Chung, Chull Hwan Abstract: 경기도 의왕시 포일동의 후기 플라이스토세 퇴적층에 대한 화분분석 결과, 초본류 및 양치식물로 이루어진 저층의 발달과 함께 침엽수-낙엽성 활엽수 혼효림이 분포했던 것으로 나타났다. 기후조건을 반영하는 식생조성의 변화가 인지되는데, 약 43,100년 전-41,900년 전 시기에는 오늘날보다 다소 추운 한랭한 온대 기후하에서 초지식생을 수반한 침엽수-낙엽성 활엽수 혼효림이 발달하였다. 약 41,900년 전-41,200년 전 동안에는 양치식물 저층의 발달과 함께 침엽수-낙엽성 활엽수 혼효림 내에서의 아한대성 침엽수의 감소와 온대성 낙엽 활엽수의 증가가 나타나는데 이는 기후조건의 온난화를 지시한다. 약 41,200년 전-39,700년 전 시기에는 기후 한랭화에 따른 아한대성 침엽수의 증가와 식생밀도의 감소가 나타난다.

2010-01-01T00:00:00Z