Sample records for hachimantai
-
Energy Technology Data Exchange (ETDEWEB)
NONE
2001-03-01
An investigational study was conducted for the Hachimantai south region with the aim of contributing to plans to be worked out for introduction of medium-term/long-term and important geothermal development promotion surveys, estimation of the developmental resource amount, etc. In the survey, the data were widely collected/arranged on the geothermal development surveys so far made in the Hachimantai south region, and wide-area geothermal system conceptual models in this region were constructed. Based on the wide-area geothermal system conceptual models and the manual for strategic survey, the following were extracted as areas for which the existence of geothermal reservoir structures is expected: Toshichi spa and the southeast area, Kakkonda-Matsukawa-Iwateyama area, Nyuto spa and the southwest area. Further, from the criteria for extraction such as the resource amount density, the natural park law and data likelihood, extracted were the Moroedake area (9km{sup 2}), Matsukawa east area (10km{sup 2}), Omatsukurayama south area (9km{sup 2}) and Kakkonda east area (14km{sup 2}). In the Monte Carlo analysis by the stored heat method, the resource amount was estimated as 5MWe, 14MWe, 4MWe and 48MWe, respectively. (NEDO)
-
Energy Technology Data Exchange (ETDEWEB)
Konishi, N; Nakamura, N; Miyamoto, T [Nippon Engineering Consultant Co. Ltd., Tokyo (Japan)
1997-10-22
For the study of a landslide that occurred at Hachimantai Sumikawa, Akita Prefecture, an airborne electromagnetic survey is conducted for the examination of the relationship between the spot of landslide and solfataric clay (bluish gray clay). The location is a cap block type structure with a Neogene green tuff overlain by accumulated lava flow, where hot water is very active. The system used in this study is capable of measurement across a very wide frequency range, and measurements are made simultaneously at five frequencies of 220Hz, 1100Hz, 5500Hz, 27,500Hz, and 137,500Hz, these frequencies meaning depth levels 5m-70m explored. It is found that the spot of landslide matches a region where resistivity is so low as to be not higher than 10ohm/m. It is also found, in the resistivity cross section analysis for the middle part of the spot of landslide, that the mass of soil that moved on the upper part of the spot is relatively high in resistivity while the part below the slide surface is low in resistivity. There is agreement between the results reported above and the results of on-site investigations. 4 refs., 6 figs.
-
Sasaki, N.; Sugai, T.
2017-12-01
Mountain wetlands, natural peatlands or lakes, with narrow catchment areas need abundant water supply and topography retaining water because of unstable water condition. This study examines wetland distribution with a focus on topography and snow accumulation, and discuss wetland evolution responding to Holocene climate change in the Hachimantai Volcanic Group, northeastern Japan, where the East Asian winter monsoon brings heavier snow and where has many wetlands of varied origin: crater lakes and wetlands in nivation hollows on original volcanic surfaces, and wetlands in depressions formed by landslides. We identified and classified wetlands using aerial photographs and 5-m and 10-m digital elevation models. Wetlands on the original volcanic surfaces tend to be concentrated under the small scarps with much snow or on saddles of the mountain ridge where snowmelt from surrounding slopes maintains a moist environment. More lake type wetlands are formed in the saddle than in the snowdrifts. That may represent that the saddles can correct more recharge water and may be a more suitable topographic condition for wetland formation and endurance. On the contrary, wetlands on landslides lie at the foot of the scarps where spring water can be abundantly supplied, regardless of snow accumulation. We used lithological analysis, 14C dating, tephra age data, and carbon contents of wetland cores to compare the evolution of wetlands, one (the Oyachi wetland) within a huge landslide and three (the Appi Highland wetlands) outside of a landslide area. We suggest that the evolution of the wetland in the landslide is primarily influenced by landslide movements and stream dissection rather than climate change. In the Appi Highland wetlands, peatlands appeared much later and at the almost same time in the Medieval Warm Period. We suggest that the development of mountain wetlands outside of landslide areas is primarily related to climate changes. Responsiveness of mountain wetlands to
-
Energy Technology Data Exchange (ETDEWEB)
Otobe, Y; Furutate, E
1992-10-31
Twenty six years have passed since the first geothermal power station was constructed in Matsuo-mura of Iwate Prefecture, Japan. This paper describes the history, the present situation and the future conception of the geothermal energy utilization in this village. This village includes Hachimantai of a vantage ground in the center and has the gross area of 233.8km[sup 2], the annual average temperature of 8.3 centigrade and the continuous snow cover period of about 100 days. The hot water leading facility was cooperatively constructed by Japan Metals and Chemicals, Hachimantai Hot Spring Development and Matsuo-mura. The total working expense is 539.3 million yen. Hot water sources are the condensate from the condenser of geothermal power plant and hot spring. This mixed hot water of 4.3 t/min is led to respective facilities. The hot water supplying channel has the length of 12.8km from the power station through the Hachimantai hot spring resort, Kamiyogi to Takaishino. Respective total areas of greenhouses using hydrothermal fluid in both districts are 1,075ha and the inlet temperature of hot water is 60 centigrade and kinds of crop are 5 like green pepper and others. Takaishino agricultural park has selected flower and ornamental plant culture such as poppy anemone, stock and statice which are suitable for this district of low temperature and insufficient sunshine. The planted area is 10,700m[sup 2]. 2 refs., 9 figs., 4 tabs.
-
Energy Technology Data Exchange (ETDEWEB)
NONE
1977-03-01
It is important for geothermal energy to develop and utilize it in a rational manner. To achieve the objective, hot water systems must be studied comprehensively and elucidated from the standpoint of the systems as a whole. The present study, standing on this viewpoint, is intended to elucidate hot water systems and establish a survey method thereon. Fiscal 1973 has selected four areas (northern Hachimantai, southern Hachimantai, Onikubi and Kuju areas) as the model study fields, and used as the main field the Onikubi area, which clearly shows the structural catchment basin. Studies were performed in this area on hydraulic hot flow rates, isotopic geology, and reservoirs. In the hydraulic hot flow rate study, the amount of rainfall, amount of flowing water, and amount of hot spring water flow-out were observed continually. In the isotopic geology study, hydrogen in hot spring water and underground water, and composition of oxygen isotope were analyzed. Estimation was made from the result thereof on water balance, heat balance, and underground residence time. In the study of reservoirs, measurements were performed inside the wells, and estimation was made on locations and sizes of the reservoirs by surveying distribution of transformed minerals and cracks. (NEDO)
-
Geological study of the landslide of the Fukenoyu thermal spring area
Energy Technology Data Exchange (ETDEWEB)
Okami, K [Dept. of Mining and Civil Engg., Fac of Technology, Iwate Univ.; Murai, S; Karasaki, H
1975-11-01
The 1973 landslide at Fukenoyu thermal spring, Hachimantai National Park, Japan, was studied geologically. The subsurface structure of the area was determined to contain faulted basement rock with distinct glide planes and a predominantly clayey mineralogy, including montmorillonite. It was concluded that the landslide was caused by the influx of water from melting snow and unstable geology. Two maps, one cross section, six stratigraphic columns, two charts and one table are provided.
-
Energy Technology Data Exchange (ETDEWEB)
NONE
2001-07-01
For grasping the characteristics of weather, climate, and natural earthquakes in and around the geothermal survey area in the Appi district, Iwate Prefecture, observation data of weather stations or the like in the neighborhood were collected and put in an easy-to-use order. Weather and earthquake data of the 1990-1999 decade were collected and subjected to statistical processing. Weather in the Appi District Survey C area is characterized in that it assumes the Japan Sea side pattern with much snow in winter and much rain in the rainy season. In the other seasons, however, it assumes the Pacific side inland pattern. Weather data in the Appi district and its vicinity are deemed to be similar to the values observed at the Hachimantai weather station. The area covered by the survey, however, is higher than the Hachimantai weather station by 400-900m, and therefore is that much colder and has more rain and snow. As for earthquakes, a total of 647 were recorded in the decade 1990-1999. In the Appi District Survey C area, which is approximately 20km times 20km large, suffered 31.1 events/month in 1998, which indicated a great rise in seismic occurrence. The rise is now attributed to the volcanic activity of Mt. Iwate which is deemed to be waning. (NEDO)
-
Energy Technology Data Exchange (ETDEWEB)
NONE
1976-03-01
This paper reports the achievements in the following study items: (1) studies on the AFMT method, (2) observation of heat dissipation by using infrared thermal images, (3) evaluation on the annular topographic pattern in the Hachimantai area identified from the Landsat satellite images, (4) studies on the Tamagawa welded pyroclastic rocks, (5) studies on minerals transformed from the Tamagawa welded pyroclastic rocks, and (6) a method to analyze ground temperature data by using graphic display. Items 2 and 6 in the studies are on the heat balance method, and Item 3 is on remote sensing. Items 4 and 5 were performed as the study on geologic thermometry. In Item 1, a prototype AFMT method exploration device was fabricated, and field experiments were performed in the Onuma area in the Hachimantai wide-area geothermal experiment field. The experiment placed importance on finding problems in transmission and reception of signals from an artificially fluctuating magnetic field, whose result was found greatly contributive to understanding the physical phenomena. However, it was not possible to reach a level to analyze geological structures from the data. In Item 2, simple meteorological observation was performed on ground surface temperature distribution by using an infrared radiation thermometer of remote sensing type. Development was made on a method to measure natural heat dissipation amount from heat balance on the ground surface. (NEDO)
-
Hydrogen and oxygen isotope ratios of geothermal waters in the southern hachimantai area
International Nuclear Information System (INIS)
Matsubaya, Osamu; Etchu, Hiroshi; Takenaka, Teruo; Yoshida, Yutaka.
1985-01-01
Geothermal waters from the Matsukawa and Kakkonda Geothermal Plants, wells at Amihari-Motoyu, and Nyuto and Tazawako areas were isotopically studied. The geothermal waters from Mutsukawa, Kakkonda and Amihari-Motoyu have hydrogen isotope ratios similar to the local meteoric waters, while have higher oxygen isotope ratios than the local meteoric waters. This relationship of hydrogen and oxygen isotope ratios, that is called ''oxygen shift'', means that these geothermal waters are meteoric waters undergone the oxygen isotope exchange with rocks at high temperature of underground. The exygen shifts are 2 -- 3 per mil in Matsukawa and Kakkonda, and 7 per mil in Amihari-Motoyu. This difference may be important to understand the processe of water-rock interaction in this area. The geothermal waters at Nyuto and Tazawako areas also show 2 -- 3 per mil oxygen shift. The steam from the Tazawako-cho well and the hot spring water form the Tsurunoyu are estimated to be vapor and liquid phases separated form a single geothermal water of NaCl type, though the hot water from the Tsurunoyu is diluted with shallow meteoric water. (author)
-
Energy Technology Data Exchange (ETDEWEB)
1977-01-01
Geothermal energy research and development by the Sunshine Project is subdivided into five major categories: exploration and exploitation technology, hot-water power generation technology, volcanic power generation technology, environmental conservation and multi-use technology, and equipment materials research. The programs are being carried out by various National Research Institutes, universities, and private industry. During 1976 and 1977, studies were made of the extent of resources, reservoir structure, ground water movement, and neotectonics at the Onikobe and Hachimantai geothermal fields. Studies to be performed in the near future include the use of new prospecting methods, including artificial magnetotellurics, heat balance calculation, brightspot techniques, and remote sensing, as well as laboratory studies of the physical, mechanical, and chemical properties of rock. Studies are continuing in the areas of ore formation in geothermal environments, hot-dry-rock drilling and fracturing, large scale prospecting technology, high temperature-pressure drilling muds and well cements, and arsenic removal techniques.
-
Geological remote sensing-evaluation of image data
Energy Technology Data Exchange (ETDEWEB)
Nagatani, H
1977-01-01
During the nationwide geothermal investigation program (Japan) begun in 1973, five districts were chosen for evaluation of the effectiveness and limitations of aerial thermography. Using thermal images of Ibusuki City and Yamakawa-cho, geothermal resource areas were detected and related fracture zones were established by combining the thermal imagery and geological maps. At Ibusuki City, it was determined that the heat source was the Ata caldera, and that a fracture system connecting it to Lake Ikeda provides a conduit for geothermal fluids. Image plotting of thermal anomalies in the Hachimantai geothermal field was found to be an effective method for monitoring variation in thermal activity. LANDSAT imagery was anlayzed and lineament systems were detected in the mountains of the Kanto district. Followup of LANDSAT data by mapping teams confirmed a fault which intersects the major Kamitsuna fault in that district. This successful use of remote sensing data is encouraging but it is possible to draw only limited conclusions from it at present. Further refinement of analytical techniques is required.
-
Isotopic and chemical features of hot springs in Akita Prefecture
International Nuclear Information System (INIS)
Matsubaya, Osamu
1997-01-01
All over the Akita Prefecture, many hot springs are located. Most of them are of meteoric water, fossil sea water and volcanic gas origins. In the Ohdate-Kazuno area, moderate temperature hot springs of meteoric water origin are found, which may exist as rather shallow formation water in the Green Tuff formations. On the contrary, high temperature geothermal waters of meteoric origin, which are used for power generation, are obtained in two volcanic area of Hachimantai and Oyasu. Those geothermal waters are expected to come up through vertical fissures from depth deeper than 2 km. The difference of these two manners of meteoric water circulation should be necessarily explained to understand the relationship of shallow and deep geothermal systems. About some hot springs of fossil sea water origin, the relationships of δ D and Cl - don't agree to the mixing relation of sea water and meteoric water. This may be explained by two different processes, one of which is mixing of sea water with saline meteoric water (Cl - ca. 12 g/kg). The other is modification of δD by hydrogen isotopic exchange with hydrous minerals underground, or by exchange with atmospheric vapor during a relic lake before burying. (author)
-
Energy Technology Data Exchange (ETDEWEB)
Nagano, K [Muroran Institute of Technology, Hokkaido (Japan)
1997-10-22
A study has been performed on underground cracks working as a geothermy reservoir layer, with respect to characteristics of elastic waves propagating with their energy concentrated on a boundary between rocks around the cracks and fluid in the underground cracks, or `crack waves`. The study has modeled a multi-crack reservoir layer according to the three-layer structure of the fluid layer and low-velocity solid layers around the former layer, whereas crack waves propagating therein were discussed for their dispersion characteristics. As a result of discussions, a guideline to the crack wave measurement at actual fields was put together as follows: because the low-velocity layer affects the dispersion characteristics of the crack waves, the structure and characteristics of the multi-crack reservoir layer may possibly be evaluated by measuring the velocity of the crack waves; evaluating the low-velocity layers requires proper selection of frequency of the crack wave to be measured; for example, at the Higashi Hachimantai field, a crack wave of several hundred hertz must be analyzed; and thickness of the low-velocity layers around main cracks, which can be estimated from the velocity of the crack wave is two meters at the greatest. 6 refs., 3 figs., 2 tabs.
-
Energy Technology Data Exchange (ETDEWEB)
Tanaka, K; Moriya, H; Asanuma, H; Niitsuma, H [Tohoku University, Sendai (Japan)
1997-05-27
As characterization of artificial cracks formed underground by using the water pressure fracturing method, experiments have been carried out to detect relationship of pressurization and S-wave propagation time with the polarizing direction dependence. Openings are created when pressure in the vicinity of the artificial cracks increases greater than reopening pressure of micro cracks. Elastic wave velocity decreases in this region because of water in the opened micro cracks. Anisotropy is created in the S-wave propagation velocity due to influence from anisotropic reopening region when the artificial cracks are pressurized, and is separated into two components which polarize orthogonally with each other (micro splitting). Field experiments conducted at the Higashi-hachimantai field were analyzed by using wavelet transform. It was possible to detect the S-wave arrival time at high accuracy, and the arrival of an orthogonally polarized wave was observed in 0.03 to 0.11 ms after the arrival of the S-wave. Possibility was indicated on separation of the two components in the orthogonally polarized wave of the S-wave if the micro splitting is used. If this mechanism is elucidated, it may be possible to extract information on cracking systems (direction of micro crack orientation and crack density). 8 refs., 10 figs.
-
Energy Technology Data Exchange (ETDEWEB)
Takahashi, M.; Endo, H. [Geological Survey of Japan, Tsukuba (Japan)
1997-07-01
Landslide and hydrothermal explosions have occurred near the Sumikawa spa in Akita Prefecture in May 1997. Investigations were performed on correlation of fountains, hot and mineral springs and open cracks seen on aerial photographs taken immediately after the events with the present landslide and hydrothermal explosions. Going toward the Sumikawa spa on the mountaineering path along the Sumikawa river from Onuma can find a flow of valley water, which has not appeared suddenly due to the present landslide (the flow has been existing from long time ago, on which bridges have been installed). The sample water quality has low chloride ion concentration and high sulfuric acid and bicarbonate ion concentrations, and is of high-temperature volcanic gas containing a great amount of hydrogen chloride gas. The water quality was determined non-relative to the present hydrothermal explosions. On the other hand, hot springs and well waters distributed around the Akita Yaeyama and Hachimantai areas have low chloride ion concentration and high sulfuric acid ion concentration. The majority is characterized in that their Ca/Na concentration ratio is relatively low. This suggests that the areas have been formed under common geological conditions. However, the water quality is thought to show different properties due to complex influences of transformation zones and exhalation gas (hydrogen sulfide). 6 refs., 2 figs., 1 tab.
-
Energy Technology Data Exchange (ETDEWEB)
NONE
1976-03-01
This paper reports the achievements of (A) studies on change in rock specific resistance due to temperature and water content, and (B) petrological, mineralogical and chemical studies on thermally transformed rocks. In the study (A), it was discovered that use of high-pressure capsules allow to obtain test samples in a condition of containing hot water as a result of studies on temperature change in rock specific resistance due to hot water content. In the measurements of geothermal gradient and heat conductivity of test drilled rock cores, the experiments revealed that there are different patterns of temperature restoration due to geological conditions and finish of wells, and properties of mud water used. The studies on thermal structures and underground structures decided shapes of measurement test samples of test drilled cores. In the measurements of heat conductivity and heat flow rate of test drilled rock cores, considerations were given on the relationship among sectional temperature increasing rate, heat conductivity and heat flow rate. The measurements of residual magnetism and magnetization in rocks described interpretation on the result of test drilled core measurement. In the study (B), aluminous sphere in the Hachimantai Onuma geothermal area is first described. Then, a description is given on the relationship between chemical constituents and electric conductivity of natural water in Mt. Akita Yakeyama and its vicinity. (NEDO)
-
Energy Technology Data Exchange (ETDEWEB)
NONE
1977-03-01
This study has begun in fiscal 1973 under a five year plan with an objective to elucidate origin and maintenance of reservoirs of geothermal fluids. To achieve the objective, estimation was made on the systems of infiltration, storage and gushing of the fluids, particularly on infiltration areas. In the hydraulic flow rate study, observation was carried out in the Onikubi area on amount of rainfall, air pressures, temperatures, electric conductivity, and pH, and in ten fluid sources on flow rates, temperatures and pH. Flow rate observation was started at three rivers. In the Kuju area, flow rate observation was started on four fluid sources. Observations were started on temperatures, electric conductivity, flow rates, amount of rainfall by using the Takenoyu geothermal steal wells, and on amount of rainfall in the Teraono and Hacchobara areas. In the study of isotopic geology, site analyses and water collection were carried out in the Kuju area for underground water in six locations, hot spring water in seven locations, and 17 test samples from two geothermal wells. As a study on reservoirs, observation was started in the southern Hachimantai area on measurement of ground fluctuation in association with steam collection. In parallel, fracture survey and gravity measurement were carried out. In order to investigate transformed geology, analytic samples were collected from 12 survey wells in the Onikubi area. A spinner flow mater was tested in that area. (NEDO)
-
Shifts in alpine lakes' ecosystems in Japan driven by increasing Asian dusts
Tsugeki, N. K.; Tani, Y.; Ueda, S.; Agusa, T.; Toyoda, K.; Kuwae, M.; Oda, H.; Tanabe, S.; Urabe, J.
2011-12-01
Recently in East Asia the amount of fossil fuel combustion have increased with economic growth. It has caused a problem of trans-boundary air pollution in the whole of eastern Asia. Furthermore, Asian dust storms contribute episodically to the global aerosol load. However, the effects of increased Asian dusts on aquatic ecosystems are not well understood. If biologically important nutrients such as nitrogen (N) and phosphorus (P) are transported via air dust, the atmospheric deposition of the dust may have serious impacts on recipient aquatic ecosystems because the biological production is limited by these nutrient elements. A previous report using sedimentary records has evaluated that atmospheric P inputs to the alpine lakes in the United States increased fivefold following the increased western settlement to this country during the nineteenth century. Since P is the most deficient nutrient for production in many lakes increase in P loading through atmospheric deposition of anthropogenically-derived dust might greatly affect the lake ecosystems. We examined fossil pigments and zooplankton remains from Pb-dated sediments taken from a high mountain lake of Hourai-Numa, located in the Towada-Hachimantai National Park of Japan, to uncover historical changes in the phyto- and zooplankton community over the past 100 years. Simultaneously, we measured the biogeochemical variables of TOC, TN, TP, δ13C, δ15N, and 206Pb/207Pb, 208Pb/207Pb in the sediments to identify environmental factors causing such changes. As a result, despite little anthropogenic activities in the watersheds, alpine lakes in Japan Islands increased algal and herbivore plankton biomasses by 3-6 folds for recent years depending on terrestrial the surrounded vegetations and landscape conditions. Biological and biogeochemical proxies recorded in the lake sediments indicate that this eutrophication occurred after the 1990s when P deposition increased due to atmospheric loading transported from Asian