Environmental conservation is very important for an area where the local people still rely on springs as water resources. Hence, understanding of seepage or recharge and discharge places of the springs is required. In the present study, geology, trends of spring electric conductivity (EC) and temperature are integrated to predict in classifying into zones related with the recharge and discharge areas at the Lembang area and its vicinity area, west Java, Indonesia. The different in configuration and permeability of geologic units and the presence of a normal fault created many springs with different characteristics of their EC and temperatures. The changes in EC and temperature of the springs during the dry and the wet seasons suggested that the variation is caused by the water recharge through precipitation and the surface water.

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'Source rock', 'Reservoir' and 'Cap rock' are called 3 factors for the formation of petroleum traps. All the process of petroleum generation, migration and accumulation, related to the above 3 factors, is called 'Petroleum System' that is a very important key word for recent petroleum exploration. Generation model was developed in the earliest stage through 1970's, which simulated petroleum generation as a reaction process of cracking of kerogen (insoluble organic matter in the source rock). Thermal history was found as a most affective parameter for the petroleum generation. For estimating paleo-heat regime, we must use in-situ thermal indicator such as vitrinite reflectance. Now we utilize a thermal maturation model to determine paleo-heat flow value from observed vitrinite reflectance. This is called calibration of model that is most important step for simulation modeling. Then we use the paleo-heat flow value as input for generation model to estimate the timing and amount of petroleum generated in the past. The model is also applied experimentally to figure out the effect of heat flow values on the generation, which is called sensitivity analysis. It is turned out from the Niigata dataset using as a standard that the higher paleo-heat flow may increase amount of generation, but the peak timing of generation is shifted to earlier stage. Thus the technique of forward modeling is applied not only for the real exploration problems but also for the educative purpose of quantification of sensitivity.

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In recent years, geothermal histories of sedimentary basin can be practically reconstructed based on kinetics of organic maturation during diagenesis and catagenesis. Kinetic factors such as activation energy (E) and preexponential factor (A) are vital for an accurate simulation of the geothermal history using specific isomerization of biomarker compounds. In the present study, the relationship between the kinetic factors and results of the simulation is discussed. The results on diagram of the two kinetic parameters method show that the computer simulation using several sets of reported kinetic factors of hopane and sterane epimerization could not re-create the historical path in accordance with the data obtained from natural samples. Historical paths matching with natural data plotted on the diagram revealed that only a pair of low E and low A, which likes factors from natural samples and is a little arranged by means of trial and error in this study, could re-created a natural history on the diagram. The re-created diagram offers a useful nomogram for consideration of an interrelationship between heating rate, paleo-maximum temperature and age. In addition, disagreements between the age of natural sample and the age on the nomogram suggest changes in heating rate in the natural samples. Our results indicate that kinetic factors from natural samples are better to use in computer simulation than those experimentally obtained. More attention should be paid for accuracy and precision of kinetic factors from natural samples.

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The organic maturities of 14 muddy rock samples from MITI Oguni borehole, Niigata Prefecture, Japan were measured by statistical thermal alteration index (stTAI) and vitrinite reflectance (Ro). The value of stTAI is determined based on the brightness of bisaccate pollen (Pinus, Podocarpus, Abies and Picea) using a transmitted-light microscope with a computer-driven digital image processor. The values of stTAI gradually decrease but those of Ro gradually increase with increasing depth of the samples. The relationship between stTAI and Ro in MITI Oguni borehole is slightly different from that in ordinary organic maturation. The difference may be attributed to the suppression of Ro. The depth for intense oil generation estimated by stTAI is about 3500m shallower than that by Ro. The reasons for this inconsistency are the suppression of Ro and/or the contamination of derived fossil pollen from older sedimentary rocks.

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Many hydrothermal ore deposits and hydrothermal alteration zones related to Late Cenozoic magmatism of the Northeast Japan Arc and the Kuril Arc are distributed in the West Hokkaido Metallogenic Province (WHMP) and the Northeast Hokkaido Metallogenic Province (NHMP) in Japan. In this article, I discuss the spatial and temporal process of hydrothermal activity and ore mineralization, and the factors controlling the heterogeneous distribution of the hydrothermal alteration zones and hydrothermal ore deposits in Hokkaido. Based on K-Ar ages of hydrothermally altered mineral, the modes of occurence of ore deposit and stratigraphic evidence of host rocks, the metallogenic period is divided into following four stages and six substages; M-I stage 19-15.5Ma, M-II stage 15.5-10Ma (M-IIa: 15.5-13.5Ma, M-IIb stage: 13.5-10Ma), M-III stage 10-5Ma (M-IIIa stage: 10-8Ma, M-IIIb stage: 8-5Ma), M-IV stage 5-0Ma (M-IVa stage: 5-2.5Ma, M-IVb stage: 2.5-0Ma). The metallogeny in the WHMP, is characterized by 1) skarn Fe deposits during M-I stage, continental-margin terranes, 2) volcanogenic massive sulfide Cu-Pb-Zn, Ba deposits and bedded Mn deposits during M-II stage, associated with submarine volcanism, 3) epithermal vein-type Cu-Pb-Zn, Mn, Au-Ag deposits during M-III to IV stage, and Land-volcanic exhalative hydrothermal S, FeS deposits during M-IV stage, related to terrestrial volcanism of the Northeast Japan inner arc. The metallogeny in the eastern part of the NHMP, similarly as one in the WHMP, is related to arc volcanism of the Kuril inner arc. The metallogeny in the western part of the NHMP is characterized by 1) epithermal vein-type Au-Ag and Cu-Pb-Zn deposits, and Land-volcanic exhalative hydrothermal S, FeS deposits during M-II to IV stage, associated with terrestrial volcanism, 2) mineralization ages (14.4 to 0.3Ma) tend to young southward, resulted from Miocene-Pleistocene terrestrial volcanism, which was initially widespread, but gradually became spatially restricted towards the south in the NHMP. The western part of the NHMP was subjected to volcanism due to uplifting mantle diapirs related the collision tectonics of Eurasian, Okhotsk and Pacific plates, resulting in regional ore mineralization and hydrothermal activity.

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An old map entitled "Figure of the Kosaka Silver Mine in May, 1870", at the General Museum Kyodo-kan of Kosaka Town, Akita Prefecture, Northeast Japan, shows the modernistic silver refinement plants in Japan, built for the first time by Takato Oshima in the end period of Edo era Keio 2nd (1867). The picture of the silver refinement plants of Kosaka Mine has not known before. The author also investigated the silver metallurgy method written by Takato Oshima at the of this map. The old map is very important in the history of Japanese science, especially mining geology and metallurgy.

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