• Journal of the Korean earth science society
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• v.35 no.7
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• pp.501-517
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• 2014

Based on a summary of the previous studies on columnar joints, this study presents research strategies and subjects to understand a formation of columnar joints, and its application in South Korea as follows; geometry of colonnade and entablature, formation mechanism and pattern change, surface morphology and internal structure, platy joint at the top and the bottom of columnar joints, crack patterns in drying starch-water slurries, using numerical models and computer graphics on joint formation, scale and geometry concerned with occurrence of volcanic rock, petrological and mineralogical study of the host rock. Additionally, more research is needed, such as deformation of column pattern during the hot state, secondary landform by alteration and weathering on the Earth's surface such as rock stream, tor and tafoni. This study will take an active role in research of columnar joint and the Cenozoic lava flow of South Korea. Results of this study will be useful to the activation of geotourism and geological field study.

• Economic and Environmental Geology
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• v.44 no.1
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• pp.11-20
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• 2011

Geological survey on the occurrence of copper oxide in Suparaura area around Abancay in the south-central part of Peru had been carried out. Geology of the area is composed of granitoids such as granodiorite, tonalite and andesitic porphyry related to Tertiary igneous activity, Ferrobamba formation with Cretaceous limestone and sandstone in descending order. Red sandstone is widely distributed and emplaced with their attitude of $N70^{\circ}W$ strike and $60^{\circ}NE$ dip. Copper oxides were mineralized along the bedding plane of red sandstone with maximum width of 30 cm. Ore-body structure bounding red sandstone strata have different occurrence characteristics with generally known porphyry system in terms of alteration, mineral assemblage and occurrence mode. Therefore, it is thought to be stratiform sediment-hosted copper (SSC) deposits genetically corresponding to Mississippi-valley type from preliminary study.

• Economic and Environmental Geology
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• v.46 no.3
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• pp.257-266
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• 2013

The geology of Sinaola state consists of Precambrian metamorphic rocks(Sonobari Complex), two Paleozoic units(lower non-differentiated metamorphic rocks and upper Carboniferous sedimentary rocks), five Mesozoic units(metavolcanic, clastic, and calcareous rocks), Cenozoic volcanic rocks, and Quaternary clastic sediments and volcanic flows. The Sinaola state is potentially rich in metallic mineral resources with lower degree of non-metallic mineral resources. They are related to a variety of geological environments and are mainly physiographically located on the Sierra Madre Occidental. Mainly known mineral deposits are of gold and silver followed by zinc, lead, copper and some iron. The state also has deposits of molybdenum, tungsten and bismuth that have been occasionally exploited. There is a reference of nickel and cobalt mineralization, but these deposits have been exploited only at a small scale.

• Journal of the Korean earth science society
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• v.33 no.7
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• pp.618-626
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• 2012

The Cretaceous fossil sites of Seoyuri in Hwasun was designated as the Korean Natural Monument No. 487 in November 2007. It provides important resources for paleoenvironmental studies, including theropod trackways, plant fossils, mudcracks, ripple marks, and horizontal bedding. The Cretaceous sedimentary strata contain a wide variety of volcanic pebbles, 5-40 cm in diameter in the lower portion and are overlain by the Late Cretaceous Hwasun andesite. Whole rock absolute K-Ar age determinations were performed on six volcanic pebbles from the Cretaceous sedimentary strata and on two samples from the overlaying Hwasun andesite. These ages indicate that the rocks belong to the period between the Turonian of the late Cretaceous (91-70 Ma) and the Pliocene age of the early Cenozoic ($63.4{\pm}1.2$ and $62.1{\pm}1.2$ Ma). Thus, the K-Ar ages indicate that the maximum geological age of the dinosaur track-bearing sedimentary deposits is about ca. 70 Ma. Therefore, it suggests that the age is comparable to the formation ages of the dinosaur footprints-bearing deposits in Sado area of Yeosu (71-66Ma).

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.450-458
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• 2018

The purpose of this study is to investigate the impact of university knowledge capital on the local business activity in the Korean local governments in the year 2015. We found that the increase of the standard deviation of university patent, scientific publications, incumbent firms, and industrial property rights raised the number of new knowledge-intensive firms to 15%, 11%, 54%, and 22%, respectively, in the local economy. In addition, the coefficient which reflects the interaction effects of the knowledge capital between universities and local industries was significant in the given area in the year. On the other hand, in the control variables, the coefficients for the size of local government, population density, and percentage of 20s~40s out of the total population in the local government were significant, showing above 90% level except for the variable of the distance between a local government and Seoul. In particular, when the knowledge capital of the university and industry coexists, the synergistic effect which has influence on the foundation of knowledge-intensive firms was meaningful despite the small scale, and these two types of knowledge capital could be complementary in creating new knowledge-intensive firms in the Korean local economy.

• The Journal of Engineering Geology
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• v.18 no.3
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• pp.321-330
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• 2008

This study, geological survey was carried out in order to study on the geology, geological structure and volcanic activity of the Ulleung-do volcano body. Ulleung-do is the volcano body of about 3,000m heights from the East Sea seabed. The geology of Ulleung-do is divided into basaltic agglomerate, trachytic agglomerate, trachyte, trachytic pumice and trachyandesite in ascending orders. The faults in caldera of Nari Basin came to make the reverse triangle style in compliance with sinking. The faults in circumference of Nari Basin are ranging with northeast-southwest direction and northwest-southeast direction. The Quaternary volcanic activities in the Ulleung-do are divided into 5 activity period. The engineering geologists and the applied geologists were not easy to apply because complicated geology of Ulleung-do. Therefore, this study supplied simple geology of Ulleung-do for them.

• Animal Systematics, Evolution and Diversity
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• v.19 no.1
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• pp.139-147
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• 2003

Burckhardt (1987) combined Aphalaridae and Spondyliaspididae into the Psyllidae, as there were no character sets which had clearly defined these three families. During the analysis on the character evolution of the psyllids from the world including Australia, there were a few different results for the taxonomy of the Spondyliaspidinae. 52 species and 28 genera in the Australian native psyllids were dissected to examine the taxonomic position of the subfamily Spondyliaspidinae. All of the dissected psyllids in the subfamily Spondyliaspidinae had one follicle in the male testes, but the subfamilies of the Psyllidae except Spondyliaspidinae were having two or more follicles. By the characteristics with living on the Eucalyptus host plants recently evolved, having just one follicle which clearly defined it from other families and experienced an explosive specific diversification in the Gondwana region, it is reasonable to separate the subfamily Spondyliaspidinae from the family Psyllidae with two or more follicles.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.97-108
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• 2012

During the last few decades, the ever-increasing knowledge of coastal morphogenic processes has made marine terraces the most recognizable, widespread and scientifically reliable records to determine both qualitatively and quantitatively the vertical movements that have affected the tectonically active coastal regions during the Quaternary. This study first aims to address the marine terrace records from Suje-ri to Suryum-ri along the coast of Gyeongju, SE Korea. Eight distinct flights of terraces, including HH YC, elevated up to 160 m above present sea level have been mapped along the coast of the study areas, and are designated $L_{II}$ to HH YC from the youngest to oldest. Based on the elevation of paleo-shoreline and inferred formation age for HH YC uplift rate since the middle Pleistocene has been estimated at 0.23 mm/year. Establishing the nature and timing of the uplift history derived from marine terraces provide a better understanding of neotectonic framework for explain enigmatic, complex landscape evolution in the Korean peninsula.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.153-163
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• 2012

The Earth's surface deforms vertically in response to a variety of sources relating to lithospheric and sub-lithospheric processes, and distinguishing the continental mechanisms for vertical motions of the lithosphere remains a fundamental challenge in geosciences. A key prerequisite to the challenge is documentation of the temporal and spatial pattern of vertical motions in different tectonic settings. This study is aimed at elucidating the geodynamic factors that can contribute to vertical motions of the Earth's surface in intraplate continental settings including the Neogene uplift in the Korean peninsula based on numerous recent achievements in relevant fields. Ultimately, deciphering the interplay between the Earth's surface and the Earth's interior processes leads us to the notion of "the importance of geomorphic landscape" as a prism to view the dynamics of the Earth's inside.

• The Journal of Engineering Geology
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• v.32 no.3
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• pp.339-350
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• 2022

There are a variety of types in tafoni formed in Miocene tuff from Golgulsa, Gyeongju. Tuff bearing tafoni was quite weathered, composed of quartz, feldspars, micas, vermiculite, chlorite, smectite, and analcite. In the early stage of the tafoni development, tafoni preferentially formed from cavities where volcanic breccias were removed or from microcavities where microcrystals were chemically altered. Small tafoni grew into large one by merging each other. The orientation of tafoni is inversely arranged to slopes, with slight inclination toward the inner cavity. Height, width, and depth of tafoni are closely interrelated: the correlation coefficients are 0.839 (width-height), 0.900 (width-depth), and 0.856 (height-depth), respectively. Removal of walls between tafoni resulted in lenticular or crescent forms, and small tafoni laterally combined to large tafoni. Large tafoni is weak because of high porosity and low strength compared to normal slope. Therefore, systematic monitoring for slope strength, pore proportion and volume, and growth of cavity needs to secure the slope stability where tafoni in Golgulsa is widespread.