• Economic and Environmental Geology
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• v.42 no.1
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• pp.55-72
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• 2009

The timing of hydrocarbon generation and expulsion from source rocks can be evaluated by reconstructing the geohistory of the basin using petroleum system modeling. The Tyee basin is generally considered having a high hydrocarbon generation potential For the southern part of the basin, the basin evolution from a structural and stratigraphic points of view, the thermal history, and the burial history were reconstructed and simulated using numerical tools of basin modeling. An evaluation of organic geochemistry for the potential source rocks and the possible petroleum systems were analysed to improve the understanding of the hydrocarbon charge of the basin. Organic geochemical data indicate that the undifferentiated Umpqua Group, mudstones of the Klamath Mountains, and coals and carbonaceous mudstones in the Remote Member and the Coquille River Member are the most potential gas-prone source rocks in the basin. The relatively high maturity of the southern Tyee basin is related to deep burial resulting from loading by the Coos bay strata. And the heating by intrusion from the western Cascade arc also affects to the high maturity of the basin. The maturation of source rocks, the hydrocarbon generation and expulsion were evaluated by means of basin modeling. The modeling results reveal that the hydrocarbon was generated in all potential source rocks and an expulsion only occurred from the Remote Member.

• Journal of Conservation Science
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• v.36 no.6
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• pp.533-540
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• 2020

Mt. Neoseongsan (NSS) is the only natural Neorok source in Korea. The geological, historical, and cultural values of NSS were recognized in 2013, and NSS has since been designated and maintained as a natural monument (No. 547), which has restricted the research and utilization of NSS Neorok. The limited NSS Neorok supply has hindered the restoration research of traditional pigments. Recently, a large amount of Neorok has been mined from Mt. Gwangeongsan (GJS) and is expected to be the main supply source of Neorok for restoring traditional pigments. Therefore, this study analyzed the characteristics of NSS- and GJS-Neorok-based pigments to evaluate the feasibility of substituting GJS Neorok for NSS Neorok in pigments. The NSS Neorok was mostly comprised of celadonite, whereas the GJS Neorok included minerals containing glassy phases such as celadonite, cristobalite, tridymite, etc. Because both Neorok samples were vitrified under identical conditions, the GJS Neorok grains were larger than the NSS Neorok ones. The GJS Neorok pigment showed that the chromaticity, grain size, oil absorption, and stability varied depending on the mineral types and contents. In particular, GJS-2 and NSS Neorok showed similar mineral compositions, physical properties, and stabilities, suggesting that GJS-2 can be substituted for NSS Neorok, which has been difficult to source and utilize ever since NSS was designated as a natural monument.

• Korean Journal of Heritage: History & Science
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• v.47 no.1
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• pp.82-101
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• 2014

The purpose of this study was to survey and analyze the origin story and the legends associated with Yongyudam(龍遊潭, Dragon Creek), its scenic and spatial description in Climbing Writings(遊山記: Yusangi Notes), its geographical and geological features, its surrounding remains and letters chiseled on the rocks through the field study and the study on literatures associated with it so to identify its significance and value and then to ensure justification on preservation of Yongyudam scenic site. Conclusions of this study are as follow. As the traditional scenic place 'Geumdae-Jiri(金臺智異)' representing Hamyang-gun(咸陽郡) depicts Mount Cheonwangbong and 'Yongyudong Village(龍遊洞)', ancient maps and literatures have positioned Yongyudam as the center of Eomcheon-river Creek as well as the representing scenic site of Yongyudong Village. Core images in the spatial awareness of Yongyudam described in our ancestors' Climbing Writings Notes on Jirisan Mount are 'geographical and scenic peculiarity associated with swimming dragons', 'potholes in various shapes and sizes scattered on rocks', 'loud sound generated by swirling from shoals' and 'the scenic metaphor from the dragon legend', which have led scenic features of Yongyudam scenic site. In addition, significant scenic metaphors from legends such as 'Nine Dragons and Ascetic Majeog' and 'Kasaya Fish' as well as 'the Holy Place of Dragon God', the rain calling magic god have descended not only as the very nature of Yongyudam scenic site but also the catalyst deepening its mystic and place nature. On the other hand, Jangguso Place(杖?所, Place of Scholars) in the vicinity of Yongyudam was the place of resting and amusement for scholars from Yeongnam Province, to name a few, Kim Il-son, Cho Sik, Jung Yeo-chang and Kang Dae-su, where they experienced and recognized Jirisan Mount as the scenic living place. Letters Carved on the rocks at Jangguso Place are memorial tributes and monumental signs. Around Yongyudam, there are 3 stairs, letters chiseled on the rocks and the water rock artificially built to collect clean water, which are traditional scenic remains detectable of territoriality as the ritual place. In addition, The letters on the rock at Yongyudong-mun(龍遊洞門) discovered for the first time by this study are the sign promoting Yongyudam as the place of splendid landscape. The laconism, 'It is the Greatest Water in Jirisan Mount(方丈第一山水)' on a rock expresses the pride of Yongyudam as the representing scenic place of Mount Jirisan. Other than those, standing rocks such as Simjindae Rock, Yeong-gwidae Rock and Ganghwadae Rock show the sign that they are used as amusement and gathering places for ancestor scholars, which add significance to Yongyudam. By this study, it was possible to verify that Yongyudam in Mount Jirisan is not simply 'the scenic place in the tangible reality' but also has seamlessly inherited as the traditional scenic attraction spiritualized by overlapped historical and cultural values. Yongyudam, as the combined heritage by itself, shows that it is the product of the place nature as well as unique ensemble of cultural scenic attraction inherited through long history based on natural scenery. It is certain that not only the place value but also geographical, geological, historical and cultural values of Yongyudam are the essence of traditional scenic attraction, which should not be disparaged or damaged by whatever political or economic interests and logics.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.38-50
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• 2008

The site-specific seismic responses and corresponding seismic hazards are influenced mainly by the subsurface geologic and geotechnical dynamic characteristics. To estimate reliably the seismic responses in this study, a geotechnical information system (GTIS) within GIS framework was developed by introducing new concepts, which consist of the extended area containing the study area and the additional site visit for acquiring surface geo-knowledge data. The GIS-based GTIS was built for Gyeongju area, which has records of abundant historical seismic hazards reflecting the high potential of future earthquakes. At the study area, Gyeongju, intensive site investigations and pre-existing geotechnical data collections were performed and the site visits were additionally carried out for assessing geotechnical characteristics and shear wave velocity ($V_S$) representing dynamic property. Within the GTIS for Gyeongju area, the spatially distributed geotechnical layers and $V_S$ in the entire study area were reliably predicted from the site investigation data using the geostatistical kriging method. Based on the spatial geotechnical layers and $V_S$ predicted within the GTIS, a seismic zoning map on site period ($T_G$) from which the site-specific seismic responses according to the site effects can be estimated was created across the study area of Gyeongju. The spatial $T_G$ map at Gyeongju indicated seismic vulnerability of two- to five-storied buildings. In this study, the seismic zonation based on $T_G$ within the GIS-based GTIS was presented as regional efficient strategy for seismic hazard prediction and mitigation.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.583-599
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• 2008

Dokdo, small island located in the eastern end of the Korean Peninsula, has been an uninhabited island for long time due to long distance from the land. Moreover, the steep slope of volcanic tuff at Dokdo is well drained for high permeability and Dokdo has few plain areas, swamps and very thin soil layers. In this study, pollen analysis at Dokdo was attempted on the profile of organic sandy soil for the first time in Korea owing to the marine climate environment with high humidity and precipitation including snowfalls in spite of unprofitable condition geologically or geomorphologically. While many historical, political researches have been accumulated for territorial problem of Dokdo with Japan, natural scientific researches with field work are not sufficient, and few paleoecological researches have been done. As a result of pollen analysis, the ratio of the NAP(Non-Arboreal Pollen) and spore was higher than AP(Arboreal Pollen), and the vegetation change existed by showing dramatic decrease of AP at the upper layer. AP was composed of almost Pinus, and a little Alnus, Quercus, Betula, Carpinus, Picea and Ulmus. NAP was composed of Gramineae, Compositae, Chenopodiaceae Cyperaceae, Caryophyllaceae, Liliaceae, Umbelliferae, Artemisia, Lobelia, Rumex, Polygonum. Increase of the NAP such as Gramineae, Artemisia and Chenopodiaceae, they would mostly have been transported from the other areas because agricultural activity is impossible at Dokdo. While one reason of Pinus thunbergii decrease could be regarded as environmental change, the other reason would be lumbering of pine trees by human activity which is adapted to Dokdo environment.

• Korean Journal of Heritage: History & Science
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• v.46 no.3
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• pp.68-77
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• 2013

This report is based on the investigation of potholes which are formed by fluvial erosion. A pothole is called so because it is a hole that looks like a coffeepot. The results of previous studies are applied to the 'Jakgwaecheon Porthole' of this study. The study is focused on the dimension and morphology of the Pothole and investigates the effects of stream sediments, river flow, geological structural lines, etc. on the formation of potholes. As a result of measuring 61 potholes in this area, we recognized that the elliptical dish-shaped cross sections are dominant and inferred that their longitudinal direction on the plain is affected by the direction of the stream flow. Also, 'Jakgwaecheon Pothole' is very characterized in terms of scale and morphology. Furthermore, it is harmonious with the beautiful landscape, humanity, and historical values and it can be suggested that it is qualified to be registered as a geoheritage structure.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.128-140
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• 2021

This study applied the theory of Landscape Ecology to representative resources of Jeju Olle-gil, which is a representative subject of walking tourism, to identify ecological characteristics and to establish a technique for landscape ecological analysis of Olle-gil resources. Jeju Olle Trail type based on the biotope type, major land use, vegetation status around Olle Trail and roads were divided into 12 types. Based on the type of ecological tourism resource classification, the Jeju Olle-gil walking tourism resource classification was divided into seven types of natural resources and seven types of humanities resources, and each resource was characterized by Geotope, Biotope, and Anthropopope, just like the landscape ecology system. Geotope resources are strong in landscape characteristics such as coast and beach, rocks, bedrocks, waterfalls, geology and Jusangjeolli Cliff, Oreum and craters, water resources, and landscape viewpoints. The Biotope resources showed strong ecological characteristics due to large tree and protected tree, Gotjawal, forest road and vegetation communities, biological habitat, vegetation landscape view point. Antropotope include Culture of Jeju Haenyeo and traditional culture, potting and lighthouses, experience facilities, temples and churches, military and beacon facilities, other historical and cultural facilities, and cultural landscape views. Jeju Olle Trail The representative resources for each type of Jeju Olle Trail are coastal, Oreum, Gotjawal, field and Stonewall Fencing farming land, Jeju Village and Stone wall of Jeju. In order to learn about the components and various functions of the resources representing the Olle Trail's ecological culture, the landscape ecological technique was interpreted. Looking at the ecological and cultural characteristics of coastal, the coast includes black basalt rocks, coastal vegetation, coastal grasslands, coastal rock vegetation, winter migratory birds and Jeju haenyeo. Oreum is a unique volcanic topography, which includes circular and oval mountain bodies, oreum vegetation, crater wetlands, the origin and legend of the name of Oreum, the legend of the name of Oreum, the culture of grazing horses, the use of military purposes, the object of folk belief, and the view from the summit. Gotjawal features rocky bumps, unique microclimate formation, Gotjawal vegetation, geographical names, the culture of charcoal being baked in the past, and bizarre shapes of trees and vines. Field walls include the structure and shape of field walls, field cultivation crops, field wall habitats, Jeju agricultural culture, and field walls. The village includes a stone wall and roof structure built from basalt, a pavilion at the entrance of the village, a yard and garden inside the house, a view of the lives of local people, and an alleyway view. These resources have slowly changed with the long lives of humans, and are now unique to Jeju Island. By providing contents specialized for each type of Olle Trail, tourists who walk on Olle will be able to experience the Olle Trail in depth as they learn the story of the resources, and will be able to increase the sustainable use and satisfaction of Jeju Olle Trail users.

• Journal of Life Science
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• v.27 no.2
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• pp.247-266
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• 2017

Cordyceps is a traditional Chinese medicinal herb well-known in China, Korea and Japan since B.C. 2,000. The original entomopathogenic fungus, Cordyceps sinensis belonging to the genus Cordyceps could not be found inside Korean peninsula due to the absence of the host insect for the corresponding entomogenous fungus. The development of artificial production methods of Korean type Cordyceps using the silkworm Bombyx mori as in vivo culture medium for the the entomopathogenic fungus Paecilomyces tenuipes is the first, and wonderful occasion in the research history of insect industry of this global world. The aim of this article is to review the historical research background, mass-production methods, and pharmacological effects of the silkworm-dongchunghacho (Paecilomyces tenuipes) which is a newly developed Korean medicinal insect-borne mushroom, and another non-insect-borne medicinal mushroom (Cordyceps militaris and Cordyceps pruinosa). Their biological actions include anti-tumor, immunostimulating, anti-fatigue, anti-stress, anti-oxidant, anti-aging, anti-diabetic, anti-inflammatory, anti-thrombosis, hypolipidaemic and insecticidal effects. The bioactive principles are protein-bound polysaccharides (hexose, hexosamin), cordycepin, D-manitol, acidic polysaccharide etc. Protein-bound polysaccharides and n-butanol fractions were demonstrated to show a significant anti-tumor activities but did not show a cytotoxicities. D-mannitol exhibited a significant prolongation of the life span in tumor bearing mice. Ergosterol did not show an efficient anti-tumor activity, but showed a significant phagocytosis enhancing activity. Anti-tumor activity of silkworm-dongchunghacho might be attributed to immuno-stimulating activities rather than cytotoxic effects [164]. Also this review comprises the breeding of Dongchunghacho varieties, optimization of culture conditions, improvement of learning and memory by Dongchunghacho, application of them as foods and chemical constituents.

• Economic and Environmental Geology
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• v.45 no.3
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• pp.317-333
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• 2012

The Yeongweol Group is a Lower Paleozoic mixed carbonate-siliciclastic sequence in the Taebaeksan Basin of Korea, and consists of five lithologic formations: Sambangsan, Machari, Wagok, Mungok, and Yeongheung in ascending order. Sequence stratigraphic interpretation of the group indicates that initial flooding in the Yeongweol area of the Taebaeksan Basin resulted in basal siliciclastic-dominated sequences of the Sambangsan Formation during the Middle Cambrian. The accelerated sea-level rise in the late Middle to early Late Cambrian generated a mixed carbonate-siliciclastic slope or deep ramp sequence of shale, grainstone and breccia intercalations, representing the lower part of the Machari Formation. The continued rise of sea level in the Late Cambrian made substantial accommodation space and activated subtidal carbonate factory, forming carbonate-dominated subtidal platform sequence in the middle and upper parts of the Machari Formation. The overlying Wagok Formation might originally be a ramp carbonate sequence of subtidal ribbon carbonates and marls with conglomerates, deposited during the normal rise of relative sea level in the late Late Cambrian. The formation was affected by unstable dolomitization shortly after the deposition during the relative sea-level fall in the latest Cambrian or earliest Ordovician. Subsequently, it was extensively dolomitized under the deep burial diagenetic condition. During the Early Ordovician (Tremadocian), global transgression (viz. Sauk) was continued, and subtidal ramp deposition was sustained in the Yeongweol platform, forming the Mungok Formation. The formation is overlain by the peritidal carbonates of the Yeongheung Formation, and is stacked by cyclic sedimentation during the Early to Middle Ordovician (Arenigian to Caradocian). The lithologic change from subtidal ramp to peritidal facies is preserved at the uppermost part of the Mungok Formation. The transition between Sauk and Tippecanoe sequences is recognized within the middle part of the Yeongheung Formation as a minimum accommodation zone. The global eustatic fall in the earliest Middle Ordovician and the ensuing rise of relative sea level during the Darrwillian to Caradocian produced broadly-prograding peritidal carbonates of shallowing-upward cyclic successions within the Yeongheung Formation. The reconstructed relative sea-level curve of the Yeongweol platform is very similar to that of the Taebaek platform. This reveals that the Yeongweol platform experienced same tectonic movements with the Taebaek platform, and consequently that both platform sequences might be located in a body or somewhere separately in the margin of the North China platform. The significant differences in lithologic and stratigraphic successions imply that the Yeongweol platform was much far from the Taebaek platform and not associated with the Taebaek platform as a single depositional system. The Yeongweol platform was probably located in relatively open shallow marine environments, whereas the Taebaek platform was a part of the restricted embayments. During the late Paleozoic to early Mesozoic amalgamations of the Korean massifs, the Yeongweol platform was probably pushed against the Taebaek platform by the complex movement, forming fragmented platform sequences of the Taebaeksan Basin.