• 자원환경지질
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• 제21권4호
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• pp.335-348
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• 1988

The author aimed to describe the volcano-stratigraphy and petrology of the volcanic mass in the Koheung peninsula, South Cheolla province. The volcanic mass is composed of the volcanics and intrusives of late Cretaceous which extruded the Pre-cambrian metamorphic(Jirisan gneiss complex) and the early Cretaceous sedimentary(Duwon Formation) basement. The volcanic pile consists of, in ascending order, Bibongsan andesite, Koheung tuff and breccia, and Palyeongsan welded tuff, and are intruded by ring intrusives( intrusive breccia, andesite porphyry, intrusive rhyolite and fine-grained quartz-diorite) and central pluton(diorite, quartz monzodiorite, biotite granite and micrographic granite). Bibongsan andesite mainly consists of andesite tuff and lava. Koheung tuff consists of alternation of fine tuff, coarse tuff and lapilli tuff, and Palyeongsan welded tuff which overlies Koheung tuff, comprises K-feldspar and quartz phenocrysts, elongated brown fiamme, lithic fragments in matrix of devitrified brown glass shards, and mainly consists of rhyodacite to rhyolite vitric ash-flow tuff. The results of petrochemical studies of the igneous rocks suggest that the rocks were a serial differentiational products of fractional crystallization of calc-alkaline magma series. This study reveals that the volcanic mass in this area is inferred to the remnant of the resurgent cauldron, measuring 30 by 25 km in diameter. The cauldron block was lowered at least 1,000 m by ring fault displacement.

• 자원환경지질
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• 제27권1호
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• pp.11-28
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• 1994

The Anyang Feldspar Mine is located in Seoksu Dong, Anyang City, Kyeonggi Do, Korea and has a long exploitation record that is once produced high grade sodium feldspars, for glaze. Geologically, This area is mainly composed of Mesozoic Jurassic biotite granite (Anyang granite) which intruded Precambrian Kyeonggi Gneiss Complex outcroped near the mining area. The deposit is localized on the southwest hill side of Anyang granite batholith and is confined in hydrothemal alteration zone formed by sodium-rich alkali hydrothermal fluids along the fractures of leucocratic granite showing later differentiation facies in the biotite granite. The hydrothermal alteration is characterized by albitization, sericitization, and desilication. The microscopic observation and EPMA, XRD analysis of the feldspar ores show that major minerals are albite and quartz and accessory minerals are orthoclase and sericite, and they are rarely associated with perthite, fluorite, zircon, kaolinite, molybdenite, microcline and iron-oxide. In the REE pattern, the strong negative Eu anomalies of the feldspar ores indicate the influence of feldspar fractionation and show similiar pattern of the host leucocratic granite. The filling temperature of quartz crystals in ore zone ranges from $276^{\circ}C$ to $342^{\circ}C$, and it is inferred that the alteration occurred by the hypothermal solution.

• 자원환경지질
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• 제23권1호
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• pp.73-79
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• 1990

Controlled source audio-frequency magnetotelluric (CSAMT) has the great advantage of efficient mapping resistivity distribution and relatively deep depth of investigation. Moreover, CSAMT may be regarded more attractive than audio-frequency magnetotelluric in the sense of the strong and controllable signal. However, it has the problem such as undershoot and/or near-field effect that is hard to be interpreted if the interpretation method of MT is directly applied. The problem arises from the existance of controlled source which makes CSAMT attractive. So the characteristics of CSAMT response should be thoroughly understood prior to interpretation stage. In this study, numerical modeling program for horizontally layered earth was developped for the interpretation of CSAMT field data. CSAMT field survey was run as a follow-up to resistivity dipole-dipole study over the same survey line at Bongmyung coal mine. The survey used a grounded dipole source 2 Km in length and located 7.5Km south in this study. A good agreement between field CSAMT data and calculated data was demonstrated even in geologically complex earth situations.

• 자원환경지질
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• 제33권3호
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• pp.195-204
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• 2000

order to investigate physical characteristics and element concentrations of sediments, coastal bottom sediments were collected at 20 stations in the vicinity of Youngkwang Nuclear Power Plant. After air drying of samples in the laboratory. article size distribution was examined by Master sizer (X-350F), radio-activity by HPGe ${\gamma}$-spectrphotometer, and element concentrations by ICP-AES and AAS. According to particle size analysis , sediments are mainly composed of silt fraction weith 23% of sand, 65% of silt and 12% of clay on average. Most sediments are derived from muddy environment that silt dominates with the characteristics of 5.3${\varsigma}$ mean particle size, poorly sorted, very fine skewed and lepto-kurtic. Only two sediments are well sorted with sandy silt owing to wind, winnowing action, tide and current andits complex reactions. Element concentrations in the coastal bottom sediments are relatively high at finer sediment and show significant relationship with grain size. Index of geoaccumulation by heavy metals at every sampling station is classified as practically unpolluted. The radioactivities of the sediments were measured for 15 isotope elements, and 2 elements of K-40 and Cs-137 were detected in most sediments. The K-40 is the natural nuclide and the artificial nuclide of Cs-137 was thought to be derived from the fallout of past nuclear weapon test. The results of correlation coefficient between grain size and radioactivity shows that the activity of Cs-137 significantly increases in finer grain.

• 자원환경지질
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• 제17권2호
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• pp.91-100
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• 1984

The Gwangyang gold deposits geologically consist of granitic gneiss, metatectic gneiss and porphyroblastic gneiss which correspond to Jirisan gneiss complex. The formations of Gyeongsang system lies unconformably on these gneisses and are intruded by diorite, porphyritic andesite and Bulgugsa granites. Goheung districts are composed of quartz schist, andesitic rock, tuff and granite. The Gwangyang gold deposits are gold bearing fissure filling veins. The vein thickness varies from 15cm to 40cm and they consist of 7-10 layers in parallel. The Goheung copper deposits are sulphide bearing quartz veln which filled the fracture in andesitic rock and biotite granite. The contact zone of these rocks is partially altered. The mineral paragenesis of the Gwangyang and Goheung districts is pyrite, arsenopyrite, pyrrhotite, chalcopyrite, sphalerite, galena, sericite, quartz and calcite. The variation trends of FMA and A'KF triangular diagrams and the differentiation index (norm, Q + Or + Ab) versus oxides diagrams is similar to the Gyeonsang basin igneous rocks. From the trace element analysis of 10 samples of country rocks, wall rocks and veins, the distribution of copper and lead contents display a correlative distribution pattern in relation to gold and silver. Homogenization temperature of fluid inclusions range from $200^{\circ}C$ to $270^{\circ}C$ in quartz from the Gwangyang gold vein and the size of fluid inclusion range from 0.01mm to 0.04mm. The fluid inclusions are mainly one or two phase and the filling degree of the inclusions varies from 85 to 95.

• 자원환경지질
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• 제24권1호
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• pp.43-55
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• 1991

The Imgye area, in the NE Taebaegsan Region, consists of Precambrian granites and schist complex at the base and Paleozoic sedimentary rocks and amphibolite at cover. The granites in the area were previously thought to be Paleozoic in age, but recent geochronological data yields isotopic age ranging from $1837{\pm}82Ma$ to $2108{\pm}82Ma$ by Rb-Sr whole rock method. Therefore, basement-cover relations in the area should be reexamined. During the study, mylonite zone recognized along the contact boundary between Precambrian granites and Cambrian Jangsan Quartzite Formation. Mylonite zone has 150 - 250 m in width. Mylonitic rocks can divide into two groups; quartz mylonite derived from Jangsan Formation and mylonitic granites from Precambrian granites. Intensity of mylonitic foliation decreased toward the north. Amphibolite occurs as an intrusive sills within mylonite zone. Mineral fabrics and small scale shear zones are commonly seen in amphibolite. It indicates that intrusive age of amphibolite is synchronous to the formation of mylonite zone. Mylonite zone was reactivated as ductile thrust faults and forms the hinterland dipping imbricate zone during the Cretaceous Bulkuksa Orogeny. The near parallelism of mineral stretching lineation and long axis of strain ellipes indicates that the area is affected by a homogeneous pure shear flattening together with the variable components of simple shear.

• 지질공학
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• 제1권1호
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• pp.38-53
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• 1991

지하공동의 설계는 지반이 본래 가지고 있는 물리적 특성을 최대한 이용하는 것을 기본 개념으로 하므로 지반자체의 복잡다양한 역학적 특성들을 평가하여 설계에 반영하는 것은 지극히 어려운 일이며, 이러한 특성들을 일률적으로 평가하는 것도 거의 불가능하다. 컴퓨터의 발달과 수치해석 기술의 적용이 본격화 되기까지는 지반의 거동을 지배하는 몇가지 주요요소의 정성적 혹은 정량적 특성에 의하여 지반을 몇가지 등급으로 분류하여 통계자료의 분석 및 경험적 판단에 의해 설계를 수행하여 왔다. 지하공동구조물 설계시으 지반거동해석은 이완영역의 가정에 의한 방법, 경험적 접근법에 의한 방법 및 최근에 와서 수치해석 기술의 발달에 따라 주로 사용되는 공학적 해석 방법에 의한 지반거동해석 등으로 구분하여 정리하였다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권6호
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• pp.18-31
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• 2013

This study was performed to examine use of the pump-and-treat method for remediation of TCE, CF and CT in groundwater contaminated by DNAPL. The Woosan industrial complex is located in Wonju, about 120 km east of Seoul, Korea. Two pumping wells (KDPW7 and KDPW8) and five monitoring wells (KDMW7, KDMW8, KDMW9, KDMW10, and SKW2) were installed for the test. An asphalt laboratory is a main source of the extensive subsurface contamination at this site. To evaluate change in the concentrations of TCE, CF, and CT in groundwater in the study area, three rounds of pump-and-treat pilot tests were performed (6 July to 6 August, 22 August to 6 September, and 19 September to 2 December in 2011). The groundwater levels and the concentrations of TCE, CF, and CT exhibited negative correlations in the wet season but positive correlations in the dry season, which suggests that the TCE concentrations were mainly controlled by dilution through rainfall during the wet season and by residual TCE, CF, and CT in the unsaturated zone during the dry season. These possibilities should be considered in the full-scale remediation plan.

• 자원환경지질
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• 제56권4호
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• pp.397-408
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• 2023

A total of 64 specimens of trace fossils were collected from the Jinju Formation of the construction site of Jinju Aviation Industrial Complex, and from the Haman Formation of Namhae Gain-ri fossil site. The fossils are continuously and regularly meandering sine-curve in shape. The fossil varies in morphology: width between 0.2 and 5.6 mm, wavelength between 1.5 and 28 mm, and amplitude between 0.9 and 7.9 mm; the Jinju specimens are commonly wider than the Haman ones. The ratio of wavelength to amplitude is more or less regular regardless of width of the specimen, and the linear correlation of the ratios shows that the Jinju specimens fit better than the Haman specimens. Taking all morphometric parameters, specimens in all size ranges are temporarily identified as ichnospecies Cochlichnus anguineus. In order to obtain more distinct and clearer images of Cochlichnus, we selected two specimens and applied a new imaging technology RTI. For photography of the trace fossils, 50 to 80 images were taken per set with photometric lighting close to the surface and horizontally. RTI technology clearly showed that the images of tiny fossils were improved: the surface contrast become sharper and messy and unnecessary information disappeared. Currently, RTI technology is used in many fields including preservation of cultural properties and archaeology. As a consequence, we hope to apply this technique to the field of paleontology, especially to the study of trace fossils of very small size.

• 한국지하수토양환경학회지:지하수토양환경
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• 제28권spc호
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• pp.18-39
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• 2023

Rapid development of geophysical exploration and hydrogeologic monitoring techniques has yielded remarkable increase of datasets related to groundwater systems. Increased number of datasets contribute to understanding of general aquifer characteristics such as groundwater yield and flow, but understanding of complex heterogenous aquifers system is still a challenging task. Recently, applications of data science technique have become popular in the fields of geophysical explorations and monitoring, and such attempts are also extended in the groundwater field. This work reviewed current status and advancement in utilization of data science in groundwater field. The application of data science techniques facilitates effective and realistic analyses of aquifer system, and allows accurate prediction of aquifer system change in response to extreme climate events. Due to such benefits, data science techniques have become an effective tool to establish more sustainable groundwater management systems. It is expected that the techniques will further strengthen the theoretical framework in groundwater management to cope with upcoming challenges and limitations.