• The Journal of Engineering Geology
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• v.19 no.3
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• pp.373-387
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• 2009

Many cultural heritages with various periods including the 'Three Kingdoms Period' were discovered in Chulmamyeon, Busan. Detailed geomorphological and geological investigation was performed due to archaeological importance of the study area. Aerial photographic analysis for geomorphology and analysis of vertical sedimentary sections to interpret the sedimentary characteristics were carried out. Many pebbles with specific features were discovered during the investigation. The characteristics and origin of the pebbles are analysed based on their size, rock type and shape. The study area is located in a relatively low and gentle slope compared with neighboring regions. The strong N-S trending lineaments may influence the topographic features and the distribution of wells discovered in this area. The exposed sections during excavation are divided into several layers depending on colors and materials included. Some of the layers may be developed not by nature but by human activities. The similarity of the pebbles indicates that these pebbles may artificially be collected or produced for a specific purpose. This study shows that geomorphology and geology can be important in location and development of archaeological sites. The analysis and interpretation for the origin of the pebbles indicates that geological studies can be helpful to interpretation of archaeological studies.

• 한국해양학회지
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• v.23 no.3
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• pp.110-122
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• 1988

Between the Clarion and Clipperton fracture zones of the Northeastern Pacific, nodules and crusts were collected from abyssal plain and hills by the Korea Ocean Research and Development Institute in December, 1983 aboard the R/V KANA KEOKI of the Hawaii Institute of Geophysics. Mineralogical and geochemical data of bulk nodules are obtained and compared with analyses of other studies. Mechanisms of nodule formation are discussed based on these data. Generally, the nodules of the KONOD-1 site are composed of todorokite and ${\delta}-MnO_2$. The contents of Mn, Fe, Ni, and Cu of the bulk nodules are variable and the average contents of metals are slightly lower (Mn, 21.40%; Ni, 0.9%; Cu, 0.8%) than those of nodules from other abyssal plains between the Clarion and Clipperton fracture zones. High Mn/Fe (average 3.9; maximum 5.9) and Cu/Ni (average 0.8; maximum 1.0) ratios are similar to the nodules that were formed diagenetically in the northeast Pacific. The chemical characteristics of the KONOD-1 nodules reflect their sedimentary environments; nodules with higher diagenetic signatures occur in areas of thin Quaternary siliceous ooze, and nodules of lower diagenetic influence occur in topographically irregular abyssal hill areas.

• Korean Journal of Mineralogy and Petrology
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• v.35 no.3
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• pp.183-197
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• 2022

Geochemical data, including Sr-Nd-Pb-Mg-Zn isotopes, reported on the late Cenozoic intraplate basaltic rocks in the Korean Peninsula (Mt. Baekdu, Jeongok, Baengnyeong Island, Pyeongtaek, Asan, Ganseong, Ulleung Island, Dok Island, and Jeju Island) are summarized to constrain their mantle source lithologies, and the nature of mantle end-members required. In the Sr-Nd isotope correlation diagram, Jeju basalts plot in the field of EM2-type oceanic island basalts (OIB), while the other basalts fall in the EM1-type OIB field. In Pb-Pb isotope space, Jeju basalts show a mixing array between Indian MORB and EM2 component, whereas the other basalts display an array with EM1 component. The Korean basalts were derived from a hybrid source of garnet lherzolite and recycled stagnant slab materials (eclogite/pyroxenite, pelagic sediments, carbonates) in the mantle transition zone. The EM1 component could be ancient (~2.0 Ga) K-hollandite-bearing pelagic sediments that were isolated for a long period in the mantle transition zone due to their neutral buoyancy. The EM2 component might have been relatively young (probably Pacific slab) and recently recycled clay-rich pelagic sediments. Eclogite and carbonates are unlikely to account for the EM components, but they are common in the mantle source of the Korean basalts.

• Journal of the Speleological Society of Korea
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• no.67
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• pp.21-34
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• 2005

Jeomal Cave consists of limestone. Soil distribution is very different from mountain area to piedmont area. The Cave developed in a part of the fault valley. The joints controls the low level stream orders in the cave. in this area the geological structure is close relate to the underground water flow. It is certain that the distribution of the clay came from the surface.

• Journal of the Speleological Society of Korea
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• v.45 no.46
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• pp.33-47
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• 1996

동굴이 휴양명소로 자리잡아 감에 따라 동굴에 대한 관심이 늘어나고 있는 때에 우리나라에 분포하고 있는 동굴의 구조적 특성을 밝히는 것은 중요한 일이다. 본 연구의 목적은 우리나라에 분포한 동굴을 유형별로 분류하고, 그 중 대표적인 석회동굴과 화산동굴의 구조적 특성을 밝히는 것이다. 그 결과는 다음과 같다. 첫째, 우리나라에는 260개 이상의 동굴이 분포하고 있는데, 강원도와 충청북도 지방에 75％ 이상이 집중되어 있으며, 이것은 이들 지역이 우리나라의 지체구조사 옥천지향사에 해당하는 곳이어서 석회석이 발달한 때문이다. 둘째, 우리나라의 동굴은 성인상으로 분류하면 석회동굴 ·화산동굴 ·해식동굴 ·저리굴 등으로 나눌 수 있는데, 석회동굴이 가장 많고, 화산동굴은 제주도에 주로 분포한다. 셋째, 동굴지형면에서 석회동굴은 이차 생성물의 성장으로 인해 다양한 볼거리를 제공하는 반면에, 제주도의 화산동굴은 규모면에서 세계적이라는 것이 특징이고, 몇몇 동굴에서는 해안가 패사류의 퇴적으로 인해 석화동굴에서만 볼 수 있는 이차 생성물이 발달된 곳도 있다. 마지막으로 동굴생물적 측면에서는 동굴의 깊이가 클수록 진동굴성 동물이 비교적 많이 발견된다. 또한 본토의 석회동굴과 제주도의 화산동굴 내에 분포하는 동굴생물은 다소 그 종류에서 차이가 나타나고 있다. 특히 제주도의 화산동굴에는 그곳에만 독특하게 사는 동굴생물들이 발견되어 종의 이름에 ‘제주도...’ 라고 명명하는 것이 특징이다.

• Economic and Environmental Geology
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• v.8 no.3
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• pp.147-164
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• 1975

19 amphibolite samples from the Precambrian Sobaegsan metamorphic belt including the Ogbang mine amphibolites were analyzed for 24 elements each, by wet chemical and emission spectroscopic methods. All the chemical data were evaluated by the methods outlined by Evans and Leake(1960) and Leake(1964) and by Shaw and Kudo(1965). The chemical similarity of all the studied rocks analyzed to basic igneous rocks is consistently indicated particularly by trace element abundance and variation trends. Petrography and oxidation ratios were also considered in attempting to determine the nature of the parent rocks. 3 analyses of W-bearing mafic metamorphic rocks from Sangdong area of the Ogcheon geosynclinal zone are also presented and discussed. Geochemical data for these latter rocks have been possibly derived from mafic tuffs deposited in an area of carbonate deposition.

• Journal of the Mineralogical Society of Korea
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• v.26 no.2
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• pp.87-99
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• 2013

The occurrence, mineralogical characteristics, and origin of the dolomite ores were investigated from major dolomite mines in South Korea. Mineralogical and textural properties of the ores and associated minerals were analyzed using X-ray diffraction, thin section petrography, and scanning electron microscopy. Dolomite ores were light to dark gray in color and mainly composed of dolomite in varying particle size with minor amounts of calcite, quartz and micas. Calcite, quartz, illite, feldspar, kaolin minerals, and chlorite occurred in local veins, dikes and alteration zones. Sepiolite and wollastonite occurred in the altered part of some mine. Asbestos minerals such as chrysotile and tremolite, however, were not identified in the present study. Reddish brown to yellow clay materials were mainly composed of illite, occasionally associated with kaolin minerals and smectite. These clay minerals might be a product of the local hydrothermal alteration related to the dyke intrusion and subsequent weathering. As well indicated in the previous studies, mineral composition, texture, and occurrence of the dolostone beds suggest their formation through the diagenesis of carbonate sediments deposited in the shallow sea during the Precambrian to Paleozoic period.

• The Korean Journal of Petroleum Geology
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• v.3 no.1 s.4
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• pp.28-39
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• 1995

The objective of this study is to investigate the origin of the dolomite in the Pungchon Formation of the Choseon Supergroup near Taebaeg City, Kangwondo, Korea. The Pungchon Formation is composed of limestone, dolomitic limestone, and dolomite with thin beds of flat pebble conglomerate (FPC) and mudrock. Texturally, the dolomite in the Pungchon Formation can be divided into four types; 1) coarse-sized, xenotopic dolomite in massive dolomite, 2) medium-siEed, idiotopic dolomite in flat pebble conglomerate, 3) xenotopic dolomite replacing ooids, algalnodules, and echinoderms, and 4) the dolomite in mottled fabric. The dolomite in mottled fabric can be subdivided into three types; a) coarse-sized, xenotopic saddle dolomite cement, b) medium-sized, idiotopic, cloudy-centered, clear-rimmed (CCCR) dolomite, and c) coarse-sized, idiotopic dolomite. The carbon isotopic composition of the Pungchon dolomite is in the range of $-2.8-1.4\%_{\circ}(PBD)$, suggesting that the carbon isotopic composition was buffered by the preexisting marine carbonates. Lighter oxygen isotopic values ($\delta^{18}O-15.7-8.7\%_{\circ}, PBD$) indicate that the Pungchon dolomite may have formed under high temperature in a burial diagenetic environment. The higher initial $^{87}Sr/^{86}Sr$ ratio of the Pungchon dolomite (0.7010-0.7161) than that of the coeval Cambrian seawater (0.7088-0.7092) indicates that dolomitizing fluids had been modified from the isotopic exchange with continental crust. Low Sr and Na contents(<200 ppm) of dolomite agree well with previously reported data for burial dolomite. Hifh Fe and Mn contents of the dolomite support the idea that the Pungchon dolomite may have formed in a deep burial diagenetic environment.

• The Korean Journal of Quaternary Research
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• v.3 no.1
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• pp.35-45
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• 1989

In Korean peninsula as well as in Western European Countries, we can find, reddish bands in sandy deposits of various origin. These bands (called "$B_t$ Band"), composed of fine material, are regularly intervalled and parallel to topography. This study is tring to elucidate their origin and associated milieux, with a group of methods and techniques (field survey, micromorphological analysis, granulometry, X-ray diffractometry of clay minerals...). $B_t$ Bands are not sedimentological origin. They were formed by superposition of two type accumulations in the sandy profile, triggered by different mechanisms: 1) accumulation in banded form, concerning silty heterometric material and micas, oweing to cryophoretic forces operating in course of deep freezing of sandy deposits: 2) illuviation of ferrugineous clays in the precedants bands, migrated in chelate state by soil water. The first processes are associated with very cold and humid climate in which freeze soil more than 3m in depth. The second, cold and humid climate in which podzolizattion is generalized. In case of South Korea and Western Europe, these two types of climates are not present circumstance, but Recent Quaternary (probably since the Wurm).the Wurm).

• The Korean Journal of Quaternary Research
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• v.13 no.1
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• pp.35-43
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• 1999

Goryeri archaeological site is located in the upstream valley of the Danjang River. The basement rocks of the area are composed of the Cretaceous to Palaeogene biotite granite (KbGr), acidic dyke (Kad), Milyang Andesite (Kma) and Jyunggagsan Formation. Among them Milyang Andesite and Jyunggagsan Formation are prevailed in archaeological site and they are composed of reddish brown tuffaceous shale, sandstone and conglomerate, with intercalations of acidic tuffs and lapilli tuffs. The purpose of this research is not only to compare REE pattern of the soil-sedimentary deposits with those of surrounding rocks, but also to identify vitric tephra in the soil-sedimentary deposits derived from the andesite, acidic tuff and lapilii tuff, in order to illucidate the provenance of the vitric tephra. The rare earth element(REE) of the soils and sedimentary deposits results in the same REE pattern with those analyzed from the surrounding basement rocks. This indicates that the soils and sedimentary deposits are originated from the surrounding basement rocks, most probably from the andesite and lapilli tuff. In addition, vitric tephra were identified both in the Quaternary in-situ weathered soils and sedimentary deposits (PMU-13 and PMU-17), and in the weathered surrounding lapilli tuff. These vitric tephra are considered to be different from those of Japanese AT(Aira Tanzawa) -tephra. The latter is predominant with clean, platty, bubble-walled and Y-shaped vitrics, while the former is conspicuous with those shapes of large and diverse size and devitrified, as well as having secondarily bubbled-surfaces reflecting surface weathering. The size of vitric fragments in the Goryeri site is about 300${\mu}{\textrm}{m}$ and large in size in compasion to 150${\mu}{\textrm}{m}$ of Japanese AT-Tephra. The interim results of the research are contradictary to the explanations based on a series of AT-tephra researches carried by Japanese scholar. In short, the vitric materials of the Goryeri archaeological site are most probably originated from the weathering products of the surrounding basement rocks, and are different from the AT-tephra in their size, shape and devitrification properties. Thus it is highly recommended to have a further comprehensive research which is more emphasized the magmatic genesis of these vitric tephra in addition to the external shape and morphology.