• 한국석유지질학회:학술대회논문집
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• autumn
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• pp.18-18
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• 2000

• Journal of the Korean Geographical Society
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• v.46 no.1
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• pp.1-19
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• 2011

The physical and chemical characteristics of loess-paleosol sequence in Jeongjang-ri, Geochang basin are examined using the magnetic susceptibility measurement, grain size analysis, OSL age dating, major, rare earth and trace elements analysis. The grain size characteristics of the loess-palesol sequence are obviously different from those of river sediment forming river terrace deposits and the Chinese Loess Plateau. The loess-paleosol sequence consisting of L1, L1LL1, L1S1, L1L2, S1 and L2 from top to bottom is estimated to MIS 2~MIS 6 and the river terrace to MIS 7. The compositions of major, rare earth and trace elements indicate that the sequence show more weathered characteristics than the Chinese Loess Plateau and originated from the Chinese Loess Plateau. These features are in harmony with the previous studies in Korea.

• Journal of the Mineralogical Society of Korea
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• v.31 no.1
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• pp.1-12
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• 2018

A gravity core (RS14-C2) was collected at site RS14-C2 in the continental slope to the east of Pennell-Isellin Bank of the Ross Sea (Antarctica) during PNRA XXIX (Rosslope II Project) Expedition. In order to trace the sediment source, magnetic susceptibility (MS), sand fraction, and clay mineral compositions were analyzed, and AMS $^{14}C$ ages were dated. Core sediments consist mostly of hemipelagic sandy clay or silty clay including ice-rafted debris (IRD). AMS $^{14}C$ age of core-top indicates the modern and Holocene sediments. Based on AMS $^{14}C$ dating, sediment color, MS and sand fraction, core sediments are divided into interglacial and glacial intervals. The interglacial brown sediments are characterized by low MS and sand fraction, whereas the glacial gray sediments are characterized by high MS and sand fraction. Among clay mineral compositions of core sediments, illite is highest (61.8~76.7%), and chlorite (15.7~21.3%), kaolinite (3.6~15.4%), and smectite (0.9~5.1%) are in decreasing order, and these compositions are also divided into the interglacial and glacial/deglacial intervals. During the glacial period, the high content of illite and chlorite indicate sediment supply from the bedrocks of Transantarctic Mountains under the Ross Ice Sheet. In contrast, because of decreasing supply of illite and chlorite by the glacial retreat, smectite and kaolinite contents increased relatively during the interglacial period. During the interglacial period, smectite may be transported additionally by the northeastward flowing surface current from the coast of Victoria Land in the western Ross Sea. Kaolinite may be also supplied to the continental slope by the Antarctic Slope Current from the kaolin-rich metasedimentary rock outcropped on the Edward VII Peninsula.

• Proceedings of the KSEEG Conference
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• 2000.04a
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• pp.107-108
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• 2000

• Journal of the Korean Geographical Society
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• v.42 no.6
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• pp.898-913
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• 2007

We examined soil properties and provenance of loess-paleosol sequences at the Daebo Granite area of Buan, Jeonbuk Province, South Korea. The section consists of the surface layer, Layer 1(paleosol), Layer 2(loess), Layer 3(paleosol), Layer 4(loess), and Layer 5(paleosol), from top to bottom and thickness of the exposed section is approximately 280cm. The magnetic susceptibility values show the distinct variations between the loess- and the paleosol layer. Even though pH, ORP, water content, and soil hardness do not display the obvious differences in the section, the organic content indicates the variation similar to those of the magnetic susceptibility. In the respect of the soil colors measured under 3 conditions, although the variations of the wet soil color exceedingly reflect the difference of the layers, these variations are obscure in some points in the section due to the characteristics of the Munsell color system. Based on the geomorphological properties, sedimentary structure, the difference of the major element composition and the condrite-normalized rare earth element(REE) patterns showing the clear difference from the adjacent bedrocks and stream sediments and the similarity to those of the Chinese Loess Plateau, it is suggested that the section was formed by the material originated from the Chinese Loess Plateau and peripheral areas. However, because the material experienced the alteration after sedimentation under the environment of the sediment area, it has the properties different from the material in the provenance areas. This phenomenon may result in the climatic condition of Korea, especially in precipitation.

• Journal of the Korean Geotechnical Society
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• v.34 no.8
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• pp.5-14
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• 2018

The grain size of clastic sedimentary rocks classifies the rock types and also causes of anisotropy of the rock. The anisotropy is one of the most important factors that dominates the strength and weathering behavior of rocks. The anisotropy of clastic sedimentary and igneous rocks in the Gyeongsang Basin including Yeongju, Daegu, and Busan were analyzed by magnetic susceptibility expressed by the degree of anisotropy and shape parameter. As the results of the study, the sandstone deposited under lacustrine environment unaffected by the external force shows 1.03 degree of anisotropy. The degrees of anisotropy of the rocks affected by faults and fault rocks show 1.06 and 1.14, respectively. The magnetic susceptibility of rocks is to decrease with the distance from the fault. A fresh mudstone and shale formed by fines show a similar magnitude of the degree of anisotropy to fault rock and correspond to oblate shape parameter due to their sedimentary structure. Due to these reasons, we need attention in design, construction, and maintenance of a structure constructed in mudstone and shale.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.747-752
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• 2003

This study was carried out to understand the stratigraphy and depositional environment of clayey soils that distributed in the Gadeok-do area, Kimhae plain (Nakdong estuary). For the study, SPT core sampling and magnetic susceptibility analysis were conducted. Soils in study area is classified into five sedimentary facies ascending order; sand/gravel. clay, sand/gravel, clay, interbedded sand and silty clay. Analysis of magnetic susceptibility for Gadeok-do clayey soil reveals that depositional process and environment can be divided into upper, middle and lower layer, and they are closely related to the sea level change since late Quaternary.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.369-374
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• 2003

A study of anisotropy of magnetic susceptibility (AMS) have been carried out to understand the tectonic stress field of late Cretaceous-Tertiary strata in Yangsan area. A total of 119 independently oriented core samples were collected from 9 sites throughout the area. The study results show that 5 sites are characterized by load foliation, and 4 sites by tectonic foliation. Load foliations caused by the weight of the overlying strata occur in the central part of the study area. Tectonic foliations created by compressional tectonic force show a regional variation in direction: Direction of compression axes derived from tectonic foliation in the southern part of the study area is approximately WNW-ESE, while it changes into NE-SW northern part of the study area. Such compressional directions are compatible with the lineament directions in each area.

• Economic and Environmental Geology
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• v.24 no.1
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• pp.71-79
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• 1991

Anisotropy of magnetic susceptibility (AMS), directional variation of susceptibility in a sample, indicates the relative magnitude and orientation of preferentially aligned magnetic grains in a rock sample and represents important aspects of rock fabrics. This observation leads to various studies which applied the AMS technique to numerous geological problems, especially sedimentology, petrology, structural geology, and tectonics. Since AMS is, relative to conventional methods of petrofabric measurement, quickly measured, easily interpretated, and providing quantitative data, AMS technique has evolved into a powerful tool for detection of rock fabrics and continues to draw the interest of non-specialists as well as magnetists. This paper represents the theory, techniques, and parameters of the relatively new AMS method for estimating petrofabrics and their various applications.

• Proceedings of the KSEG Conference
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• 2002.04a
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• pp.285-290
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• 2002

조사지역은 전라남도 함평군 함평읍으로부터 남쪽으로 엄다면 화양리, 학야리, 성천리 일대에 발달한 충적층으로서. 이 지역에는 남서-북동방향으로 광주단층이 통과하고 있는 것으로 추정된다. 충적층 하부에 발달한 단층을 포함한 대규모 파쇄대 파악에는 지표지질조사로서 한계가 있다. 따라서 이 연구에서는 물리탐사방법을 적용하여 충적층 하부의 대규모 파쇄대의 방향과 연장성을 파악하고자 하였으며, 사용된 물리탐사법은 전기비저항 2차원탐사, 전자탐사 그리고 자력탐사이다. 전기비저항 탐사결과 충적층 내에서 남북방향의 연장성을 갖는 전기비저항 이상대가 파악되었으나, 자력탐사와 전자탐사의 측정자료에는 이 이상대에대한 반응을 관찰할 수 없었다. 이는 전자탐사의 경우, 가탐심도가 매우 작은 EM31을 사용하였고, 또한 자력탐사는 주변 지질매체 간의 대자율 차이가 없는 것에 기인한 것으로 판단된다. 따라서 향후 지하심부의 탐사를 위해 전자탐사법중 TEM 탐사를 실시할 계획이며, 또한 낮은 전기비저항 이상대의 연장성을 정확히 파악하기 위하여 기 측정된 전기비저항 탐사 측선 사이를 탐사할 예정이다.