物理檢層에 의한 慶尙系 堆積巖類의 特性硏究

권병두,구자학 한국지구과학회 1983 韓國地球科學會誌 Vol.4 No.1

The physical characteristics of the sedimentary rocks developed in the Gyeongsang basin have been studied based on the geophysical logs which include SP, single electrode resistance, gamma ray, density and caliper logs. The rock sequences penetrated by the borehole, located in the Namji area, are portions of the Chilgok Formation and Jinju Formation which are the base of the Hayang Group and the top of the Sindong Group respectively. Although five different rock types are described on the core log, the boundaries between such rocks are not clearly indicated on the geophysical logs. It is quite apparent that such poorly sorted sediments have non-marine origin and have been severely compacted and almost completely cemented through the diagenesis process. The gamma and SP logs show that the clay content of the formation slightly increases with depth. The organic rich black shale zone of 4m thickness is clearly identified on the gamma-ray log in the top part of the Jinju Formation. The bulk density determined from the density log is about 2.6g/㎤ and does not show much variation between different rock types. This value is close to the expected matrix density of the rock sequences and the rocks are appeared to have very low porosity. The resistivity curve also does not show any clear differences according to the described rock types. This fact also indicates that both shales and sandstones have been severely altered through the diagenesis. The low resistivity peaks and the corresponding large SP deflections are appeared against the fracture zones which are clearly identified on the caliper log. The dominance of such electrokinetic potential over the electrochemical potential also indicates that the permeability of the rocks is very poor.

數種의 麻醉薺가 注入된 局所에 미치는 形態的 變化

權炳斗 全南大醫大 1975 전남의대학술지 Vol.12 No.1

제 23 차 학술대회 : 30. 식도위 문합술에 대한 임상적고찰

권병두 대한외과학회 1971 대한외과학회 학술대회자료집 Vol.- No.-

경기육괴내 주요 단층대의 지구물리학적 연구: 공주분지의 중력 및 지전기 탐사

권병두,정경자,박창업,Kwon Byung-Doo,Jung Gyung-Ja,Baag Chang-Eob 한국석유지질학회 1994 한국석유지질학회지 Vol.2 No.2

경기육괴와 옥천대의 경계부분에 위치한 백악기 퇴적분지인 공주분지의 조구조운동의 특성과 지하구조를 해석하기 위하여 분지를 가로지르는 측선을 2개 설정하여 중력탐사를 실시하고, 분지의 경계를 이루는 두 단층선에 대하여 파쇄대의 발달상태를 확인하기 위하여 쌍극자 비저항탐사를 실시하였다. 부우게이상을 구하기 위한 중력자료의 처리과정에서 원추형프리즘 모형을 이용하여 지형보정값을 계산함으로써 경사가 급한 지역에서의 보정의 효과를 향상시켰다. 중력자료의 정량적해석을 위하여 역산 및 순산모델링 (forward modeling)을 실시하였으며, 전기탐사자료를 처리하여 비저항단면도를 얻었다. 중력모델링 결과, 공주분지는 중앙부의 폭이 약 $4{\cal}km$, 남동부의 폭이 약 $2.5{\cal}km$로 지표에서 보이는 바와 같은 마름모형태로 나타났다. 분지의 깊이는 약 $700{\~}400{\cal}m$로 중앙부의 기반이 솟아오른 형태를 보이는데, 이것은 분지가 형성된 후 압축응력이 작용한 결과로 해석된다. 또한 분지내부에서 형성된 저밀도의 파쇄대가 나타나는데, 이는 분지의 생성과정이나 퇴적물이 쌓인 후에 몇차례의 단층운동이 있었음을 시사한다. 분지를 형성한 주단층 가운데, 남동경계를 이루는 단층의 파쇄대는 넓게 분포하고 지하 $1{\cal}km$ 이상의 깊이까지 연장되어 있는 것으로 나타나는 반면 북서경계의 파쇄대는 비교적 미약하게 나타났다. 이로부터 분지의 남동경계를 이루는 단층을 따라 진행된 조구조운동의 강도가 상대적으로 컸을 것으로 추측할 수 있다. 이러한 양상은 남동경계를 이루는 단층대에서 저비저항대가 두텁게 나타난 전기탐사의 결과와 잘 일치한다. The geologic structure of Gongju Basin, which is a Cretaceous sedimentary basin located on the boundary of Gyeonggi Massif and Ogcheon Belt, is modeled by using gravity data and interpreted in relation with basin forming tectonism. The electrical survey with dipole-dipole array was also conducted to uncover the development of fractures in the two fault zones which form the boundaries of the basin. In the process of gravity data reduction, the terrain correction was performed by using the conic prism model, which showed better results specially for topography having a steep slope. The gravity model of the geologic structure of Gongju basin is obtained by forward modeling based on the surface geology and density inversion. It reveals that the width of the basin at its central part is about $4{\cal}km$ and about $2.5{\cal}km$ at the southern part. The depth of crystalline basement beneath sedimentary rocks of the basin is about $700{\~}400{\cal}m$ below the sea level and it is thinner in the center than in margin. The fault of the southeastern boundary appears more clearly than that of the northwestern boundary, and its fracture zone may extended to the depth of more than $1{\cal}km$. Therefore, it is thought that the tectonic movement along the fault in the southeastern boundary was much stronger. These results coincide with the appearance of broad low resistivity anomaly at the southeastern boundary of the basin in the resistivity section. The fracture zones having low density are also recognized inside the basin from the gravity model. The swelling feature of basement and the fractures in sedimentary rocks of the basin suggest that the compressional tectonic stress had also involved after the deposition of the Cretaceous sediments.

제주도에 분포하는 화산암의 물리적특성

권병두,정호준 한국지구과학회 1993 지구과학교육 학술발표회 Vol.1993 No.-

부평 칼데라의 중력연구

권병두,황회승 한국지구과학회 1991 韓國地球科學會誌 Vol.12 No.3

Gravity survey was conducted to investigate subsurface structure of the Bupyung caldera. Two profiles of about 23 ㎞ and 21㎞ length were chosen across the caldera and gravity values were measured at 333 points on those profiles. The regional gravity trend of the survey area is mainly attributed to isostasy. The maximum negative gravity anomaly over the caldera appears to be -8.5m gal. Gravity profiles were analyzed and interpreted by using power spectrum analysis, Marquardt-Levenberg inversion and ideal-body inversion methods. The result of 2-D inversion shows the existence of the low density structure of about 8km surface width and 3km depth under the caldera. Since the caldera has three dimensional, 2-D gravity inversion results in relatively large error as compared with 3-D modeling. Fortran subroutine was coded to calculate the gravity anomalies caused by 3-D subsurface bodies. The result of 3-D modeling shows the Bupyeong caldera can be approximated by basin-shaped low density body whose depth reaches to 3㎞. At this depth level we assume that there exist a nearly flat boundary between granite batholith and metamorphic rock out side of the caldera. The negative anomaly of Bupyeong caldera appears to be caused by density contrast between low-density granite inside the caldera and surrounding metamorphic complex. Relationship between the defect mass and the diameter of Bupyeong caldera satisfies general relationship observed in world-wide volcanic calderas.

남극 킹죠지섬 바톤반도 지역의 자력 탐사 연구

권병두,좌용주,이기원 한국지구과학회 1992 韓國地球科學會誌 Vol.13 No.1

A magnetic survey was carried out at the Barton Peninsula in King George Island, Antarctica. To analyze geological features in the study area, several filtering methods in 2-dimensional wavenumber domain were used. The Barton Horst associated with volcanic activities is well revealed on the low-pass filtered anomaly map. Possible existence of small volcanic plugs or, presumably, mineralized zones are apparent at northern parts and south-western part by reduction-to-the-pole and pseudo-gravity filtering. On the 1st vertical derivative and directional filtered anomaly maps, the geological boundaries on the surface are well identified, and fault strikes along E-W or NW-SE direction appeared to be mostly dominant throughout the study area. Density and susceptibility mapping were performed using the inversion method. The apparent densities of tuffaceous rocks distributed in the southern parts and those of quartz-diorite or crystal tuff in the northern parts were computed as values up to about 2.69 g/㎤ and 2.73 g/㎤, respectively, and the apparent susceptibilities of those rocks are appeared to be about 250 × 10^(-6) CGS and 1870 × 10^(-6) CGS, respectively. These results are in accordant with those of samples measured by Garrett(1990). Therefore, it is concluded that the studied area of the Barton peninsula has been influenced by crustal movement associated with active volcanism and the surface lithology is extended to the considerable depth.

우리 나라 重力基點의 重力値 設定에 관하여

권병두 한국지구과학회 1982 韓國地球科學會誌 Vol.3 No.1

The national wide gravity survey to establish gravity values for the base reference stations in Korea was initiated by the U.S. Army. The Division of Geodesy, U.S. Army Map Service Far East (DG, USAMSFE) conducted two base station surveys in 1961 and 1964, and measured gravity values at 15 stations throughout Korea. Professor Woollard also observed 3 gravity base stations in 1964 as a part of the International Gravity Measurements. All of these surveys were tied directly to DG Base of USAMSFE in Tokyo and Tachikawa Air Force Base stations. GMIK (presently Korea Institute of Energy and Resources) also made 10 base station measurements in 1971, which are tied to USAMSFE base stations established in the previous survey. In a broader sense, all of these measurements are related to Potsdam system whose value is now recognized to be too large by about 14 mgals. In accordance with the International Gravity Standardization Net 1971 (IGSN 71), adopted and recommended by the International Union of Geodesy and Geophysics, GMIK, in cooperation with Institute of Geological Sciences of England, measured gravity values at 15 base reference stations which are tied to IGSN 71 primary base stations in London and Kyoto. The results of this survey are generally lower by about 13.8 mgals than previous values. On the other hand, the National Geography Institute established a fundamental national gravity base reference station in the back yard of the Institute's building and determined the gravity value, which is tied to the IGSN 71 value of the base reference station located in Tokyo. The measurements were made twice in 1975 and 1980 with the cooperation of Japan Geophysical Survey Institute. NGI also established four auxilliary gravity base reference stations in 1980. The author recently measured the gravity difference between two base reference stations located in Korea Institute of Energy and Resources and National Geography Institute and found the measured value is different by more than 1 mgal to that computed from the gravity values adopted by two Institutes. Therefore it is recommended to conduct a more detailed crosscheck to establish consistent base reference values throughout the country.

A Study on the Crustal Structure of the Southern Korean Peninsula through Gravity Analysis

권병두,양수영,Kwon, Byung Doo,Yang, Su Yeong The Korean Society of Economic and Environmental G 1985 자원환경지질 Vol.18 No.4

한반도 남한 지역의 지각구조를 연구하기 위하여 USAMSFE(1961~1962) 중력자료를 분석하였다. 이들 중력측정치를 IGSN 71중력치로 환산하기 위하여 -14.7mgal 보정을 실시하였으며, 중력이상의 계산에서는 GRS 67식을 사용하였다. 자료처리과정에 있어서는 polynomial fitting을 이용하여 지역중력이상과 잔류중력이상을 분리하였고, 지각의 평균두께와 지각기저면의 깊이분포를 구하기 위해 FFT(Fast Fourier Transform)를 이용한 power spectrumqnstjr과 하향연속을 실시하였다. 하향연속을 위한 필터링 과정에서 고주파수차단 필터링과 동시에 자료간의 간격을 넓히는 효과를 낼 수 있는 2차원에서의 high-cut filtering and resampling법을 개발적용하였다. 분석의 결과로는 (1) 부우게 이상이 대체로 이 지역의 지체구조선의 방향과 같은 NE-SW방향의 분포를 보이고 있으며, (2) 지각의 평균두께는 약 32km로 나타났고, (3) 지각기저면의 깊이분포는 26km~36km의 범위로서 지표면의 광역적인 지형고도를 반영하고 있으며, 동해안의 지각이 서해안보다 더 얕은 것으로 나타났다. (4) 지각평형정도를 지시해주는 측정점의 고도와 중력이상 사이의 선형회귀방정식을 계산해본 결과, 우리 나라의 지각은 다소 보상이 덜되어 있는 것으로 나타났다. The crustal structure of the southern part of the Korean peninsula has been investigated based on the results of processing and anlaysis of gravity data. The processing techniques involve i) seperation of regional and residual anomalies by polynomial fittings, ii) power spectral analyses to determine the mean depth to the crustal base, iii) a filtering operation called "high-cut filtering and resampling," and iv) downward continuation to determine the undulation of the crustal base. The Bouguer anomalies show a lineation in the NE-SW direction which is the same as that of most mountains and tectonic lines of this area. The mean crustal depth is found to be 34km. The depth of the crustal base is varying in the estimated range of 26km to 36km with a thinner crust below the east coast than that of the west coast. The relief of the crustal base is appeared to be correlated with the regional surface topography. The linear regression relations computed between elevations and gravity anomalies indicate that the crust of this area seems to be not in perfect isostatic equilibrium but a little undercompensated state.

석탄층 검층자료의 정량적 해석법 연구

권병두,손세조,손정우,Kwon, Byung Doo,Son, Se Jo,Son, Jeong Woo 대한자원환경지질학회 1988 자원환경지질 Vol.21 No.1

Geophysical well logging at various coal fields were carried out to study the characteristic response of domestic coal seams. Also a computer program is developed for quantitative analysis of coal logging data. Most coal seams penetrated by the drill holes, where the well logging were carried out, showed poor thickness and quality, and were severely altered. Therefore, majority of log data are inadequate for detailed quantitative analysis. The logs show, however, typical characteristics with related to coal seams, but interpretation should be made with caution because certain log response of demestic coals, mostly anthracite, are quite different to those of foreign coals, mostly bituminous. The developed comuter program has been proved as an effective one for identification of coal seams and lithology anslysis, and is expected to be succesfully used for coal quality analysis in cases of more diversified log data of good quality being obtained.