The purpose of this study is to clarify geological age of leucogranitic rocks in the Samcheog area. Petrographical and geochronological features of leucogranitic rock are as follows; (1) These rocks in the area can be classified into two rock types: Moogho leucogranite gneiss and Yimwon leucogranite. (2) These rocks intruded into Precambrian metasediments and are overlain by Paleozoic sedimentary rocks. (3) These rocks are distinctly showing slight foliation and containing garnet and sillimanite which produced by assimilation and contamination. (4) Rb/Sr whole rock age of these rocks indicates an isochron of $2088{\pm}8.5$ m.y. with the initial $^{87}Sr/^{86}Sr$ ratio of $0.7108{\pm}0.0007$.

최대 엔트로피 스펙트럼 분석 (Maximum entropy spectral analysis)에 관한 Burg알고리즘 (algorithm)의 계산효율과 안정성에 대하여 검토하였다. Burg의 방법은 Yule-Walker의 방법보다 계산효율이 낮을 뿐만 아니라 그의 수학적 불합리성으로 인하여 간혹 불안전할 때가 있다. 이러한 불합리성을 인공 시계열의 해석을 통하여 증명한 후 보다 안정하고 효과적인 방법을 소개하였다. 또한 파워 스펙트럼밀도 (Power spectral density)의 계산에서 Goertzel알고리즘을 이용하는 효율적인 방법도 소개하였다.

Geoje copper ore deposits are fissure filled copper veins which developed in late Cretaceous pyroclastics, andesite and shale. Mineral paragenesis reveals a division of the hydrothermal mineralization into three stages: Stage I, deposition of pyrite, magnetite, specularite, quartz and chlorite; Stage II, deposition of chalcopyrite, sphalerite, galena, tetrahedrite, aikinite, cosalite, electrum, quartz and chlorite; Stage III, deposition of barren calcite. Filling temperatures of fluid inclusions in quartz of stage I range from 171 to $282^{\circ}C$ whereas fluid inclusions in quartz and sphalerite of stage II range from 213 to $262^{\circ}C$ and from 186 to $301^{\circ}C$ respectively. Salinities of fluid inclusions in quartz of stage I range from 5.2 to 11.2 weight percent equivalent to NaCl. Salinities of fluid inclusions in quartz and sphalerite of stage II range from 6.6 to 10.9 and from 7.1 to 14.4 weight percent equivalent NaCl. Salinities of ore fluid during major mineralization stage in this deposits reveal nearly the same ranges as those of many copper deposits in Koseong copper mining district which located about 30km apart from Geoje mine. But filling temperatures of fluid inclusions formed during major copper mineralization stage in this deposits show slightly lower than those of copper deposits in Koseong copper mining district.

상동 텅그스텐 스카른의 생성온도와 동위원소가 보여준 결과는 광화용액의 근원이 마그마로부터 공급되어진 것으로 추정이 가능해 현 광체 하위부 1km 이내에 화강암류의 존재를 예측케 한바 있다. 스카른 광물군은 중앙의 운모부화대로 부터 측면으로 유체는 이동해 나가면서 평형 조건하에서 형성되어진것 같다. 광물학적 누대는 점차 외곽으로 가면서 시간이 지남에 따라 점차 확대되어 광상전반에 걸쳐 초기 광물군의 잔적을 남기면서 특징적인 스카른을 형성하였다. 중심부의 특징적인 운모-회중석대는 유체의 진화과정의 마지막 단계의 마그마 유체의 성질을 나타내 보이고 있다. 열역학적인 계산에 의한 그림을 이용해 일부 광물의 성분을 단순화시켜 스카른의 생성을 도시함으로써 정량화시켜 생성조건을 표현하였다.

분천 광산의 망간 광상은 선캠브리아기 율리통의 변성암류의 엽상 구조를 횡단하는 $N20^{\circ}E$ 방향의 단층면을 따라 열수 용액이 충진하여 형성된 열수 기원의 규산 망간 광석과 이의 표성 산화작용에 의하여 생성된 산화 망간 광석으로 구성되어 있다. 규산 망간 광석은 주로 파이록스만자이트로 구성되어 있으며 소량의 능망간석, 석영, 녹니석 및 황화황물(황철석, 황동석, 섬아연석, 방연석, 알라반다이트, 자류철석)등이 포함되어 있다. 산화 망간 광석은 엔소타이트, 버네사이트, 토도로카이트, 망가나이트 등으로 구성되어 있다. 파이록스만자이트와 능망간석의 산화과정 및 광물생성 순서는 다음과 같다. 능망간석$_{\rightarrow}^o$토도로카이트$_{\searro}^o$파이록스만자이트$_{\line(10){90}}^o{\nearro}$버네사이트$_{\rightarrow}^o$엔소타이트$_{\rightarrow}^s$ 망간나이트 (o : 산화, s : 단순한 순서) 광석을 구성하고 있는 광물들은 광학적, X선적, 적외선 흡수분광학적, 열분석에 의하여 감정 연구되었다.

Projection method has been used in the phase equilibria study. The projection is made through the saturated phase on the smaller chemical system from larger system. This decreases the number of phases which are included in the larger chemical system. In multiple projection containing plagioclase as a projection phase, there is a difference in matrix calculation when plagioclase is treated as a single composite component and separately as an albite and anorthite. The matrix calculation is considered to be more usable and easier in multiple projection. The value of the A component in the AFM system, which is the smaller system projected from the larger one, is effected and varies according to the change in the An content in plagioclase that is examined as an example.

Uraniferous black slates of the Okchon sequence occur in Koesan (northeast) through Miwon-Boun (middle) to the southwest off Taejon (southwest) within the Okchon fold belt. The Uraniferous balck slates in the southwest off Taejon are particularly well developed in Chubu (northeast) and Moksso-ri (middle) areas whereas they are less developed in Jinsan (southwest) area. The uraniferous beds range from less than a meter to 40 meters in thickness and range from less than 0.02% $U_3O_8$ (cut-off-grade) to 0.05% $U_3O_8$ in the southwestern district off Taejon. Electron microprobe analysis of uranium-minerals found in graphitic slate samples enables to estimate their major compositions semi-quantitatively so that uraninite, ferro-uranophane and chlopinite are tentatively identified. Uranium-minerals are closely associated with carbon and metal sulfides. Correlation analysis of trace element concentrations revealed that U and F.C., and U and Mo are lineary correlative respectively and their correlation coefficients are positively high whereas those of U and V, U and Mn, and U and Zr are negatively low, implying that uranium mineralization has been closely related with concentrations of carbon and molybdenum. Stable isotope analyses of pyrite sulfur range widely from +11.5% to -23.3% in ${\delta}^{34}S$ values whereas those of graphite carbon fall within a narrow range between -23.3% and -28.9% in ${\delta}^{13}C$ values. The wide range of ${\delta}^{34}S$ values suggests that the sulfur could be of meteoric origin rather than of igneous source. The narrow range of ${\delta}^{13}C$ values, which are close to those of coal, indicates that the graphite is organic carbon in origin. Therefore, it is concluded that the uranium mineralization in the Okchon sequence took place primarily in sedimentary environment rich in organic matter and sulfide ion, both of which served as the reducing agents to convert soluble uranyl complex to insoluble uranium dioxide.

The Yeongdo Island in Busan City is a remnant of the latest Cretaceous volcano, and consists geologically of andesites, rhyolite tuff, pelitic and psammitic hornfelses, lapilli rhyodacite tuff of the Yucheon Group, felsite and felsite porphyry of the Bulgugsa intrusives, and Holocene sediments in ascending order. The hornfelses are bound to the Taejongdae Formation. The stratigraphic position of the Formation is determined definitely into the Yucheon Group, thus the geologic age is approximately the same with the volcanic rocks of the Group. The sediments had been thermally metamorphosed to make pelitic and psammitic hornfelses of the albite epidote hornfels facies by the effects of active hydrothermal circulation, vaporization, and hybridization of andesitic solution, or of basification of acidic intrusives. Thus, on occasion, those hornfelses are not used to be distinguished from the andesitic rocks in the southeastern part of the Korean peninsula. The paleocurrent direction determined from several cross-beddings of the Taejongdae Formation is suggested to be from southwest to northeast. Orbicular rocks occur in hornfelsed rhyolite tuff, pelitic- and psammitic-hornfelses, and felsite porphyry at a lot of outcrops in the area of southwestern shoreline of the Yeongdo Island. Orbicules in rhyolite tuff and hornfels in the island might have originated from diffusion processes of metasomatic metamorphism carried out by hydrothermal solution rised from the intrusive adamellite which may be emplaced deeply under the Yeongdo volcanics. Those orbicules are due to metasomatic, secondary, and epigenetic origin. Proto-, multi-shelled, and multi-cored orbicules are described in the orbicular tuff. But multi-cored orbicules are not found in the orbicular fornfels. 250 tuff-orbicules numbered sporadically are in $20,000m^2$ area of the locality of orbicular tuff. About 60 hornfels-orbicules occurred sporadically are in $1,700m^2$ area of the locality of orbicular hornfels in the Taejongdae Formation. Orbicules in felsite porphyry might have originated by diffusion reaction between xenoliths and a quiescent zone in felsite porphyry magma. Those are of igneous, primary, and syngenetic origin.

The newly discovered minerals found during 30 years have been discovered with election microprobe analysis, and several other new minerals have been described largely on the basis of probe analysis. Widely used types of instrument are the wavelength dispersive spectrometer (WDS) and the energy dispersive Spectrometer (EDS), with emitted X-ray dispersed by a curved crystal that is arranged to satisfy the Bragg equation ($n{\lambda}=2dsin{\theta}$). Atomic Nos of Z 4 to 92 can be analyzed quantitatively if they present in amount exceeding 50~100ppm. The application of the microprobe in mineralogical and geological research is quantitative chemical analysis of grains as small as a few microns in diameter, individual grains in a rock or can be analyzed in thin section and polished section, analysis can be made comparatively short time, methods in non-destructure, to photographical and crystallographical information. This paper was written in order to document data evaluation procedure for quantitative energy dispersive election probe analysis.