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Yoshida, Hidekazu*; Yamamoto, Koshi*; Asahara, Yoshihiro*; Maruyama, Ippei*; Karukaya, Koichi*; Saito, Akane*; Matsui, Hiroya; Mochizuki, Akihito; Jo, Mayumi*; Katsuta, Nagayoshi*; et al.
Communications Engineering (Internet), 3, p.67_1 - 67_10, 2024/05
A capability to permanently seal fluid flow-paths through bedrock, like boreholes or underground tunnels, is needed to ensure the long-term safety and effectiveness of many underground activities e.g. CO storage, hydrocarbon field abandonment, and nuclear waste disposal. Commonly used cementitious seals may not be sufficiently durable due to chemical and physical degradation. Learning from natural calcite (CaCO
) concretion formation, a more durable sealing method was developed using a "concretion-forming solvent". The method was tested by sealing flow-paths next to a tunnel in an underground research laboratory at 350 meters depth. The flow-paths initially sealed rapidly, then resealed after disturbance by earthquakes (M5.4). The treated rock recovered its very low natural permeability, demonstrating permanent sealing that is robust.
Yoshida, Hidekazu*; Yamamoto, Koshi*; Asahara, Yoshihiro*; Maruyama, Ippei*; Karukaya, Koichi*; Saito, Akane*; Matsui, Hiroya; Mochizuki, Akihito; Katsuta, Nagayoshi*; Metcalfe, R.*
Powering the Energy Transition through Subsurface Collaboration; Proceedings of the 1st Energy Geoscience Conference (Energy Geoscience Conference Series, 1), 20 Pages, 2024/00
A capability to permanently seal fluid flow-paths in bedrock, such as natural faults/fractures, and damaged zones around boreholes/excavations, is needed to ensure the long-term safety and effectiveness of many underground activities. Cementitious materials are commonly used as seals, however these materials unavoidably undergo physical and chemical degradation, therefore potentially decreasing seal durability. In order to solve these problems, a more durable sealing method using concretion-forming resin has been developed by learning from natural calcite (CaCO) concretion formation. The sealing capability of resin was tested by
experiments on bedrock flow-paths in an underground research laboratory (URL), Hokkaido, Japan. The results showed a decrease the permeability rapidly down to 1/1,000 of the initial permeability due to calcite precipitation over a period of one year. During the experiment inland earthquakes occurred with foci below the URL (depths 2-7 km and maximum magnitude 5.4). Due to the earthquakes the hydraulic conductivities of the flow-paths sealed initially by concretion-forming resin increased. However, these flow-paths subsequently resealed rapidly, and within a few months recovered the same hydraulic conductivities as before the earthquakes. This new technique for rapidly producing long-lasting seals against fluid flow through rocks will be applicable to many kinds of underground activities.
Katsuta, Nagayoshi*; Umemura, Ayako*; Naito, Sayuri*; Masuki, Yuma*; Itayama, Yui*; Niwa, Masakazu; Shirono, Shinichi*; Yoshida, Hidekazu*; Kawakami, Shinichi*
Spectrochimica Acta, Part B, 210, p.106817_1 - 106817_11, 2023/12
Times Cited Count:1 Percentile:0.00(Spectroscopy)X-ray fluorescence (XRF) scanning of lacustrine sediments has been used to extend the approach to a wider range of elemental records in both ages and timescales of variations in past environments and climates. However, one of severe problems with effects of the XRF intensity by grain size and mineralogical composition known as "heterogeneity effects" have been pointed out. This study investigated the heterogeneity effect of Fe intensities on X-ray beam using several binary powder mixtures and lacustrine sediment cores.
Katsuta, Nagayoshi*; Takano, Masao*; Sano, Naomi; Tani, Yukinori*; Ochiai, Shinya*; Naito, Sayuri*; Murakami, Takuma*; Niwa, Masakazu; Kawakami, Shinichi*
Sedimentology, 66(6), p.2490 - 2510, 2019/10
Times Cited Count:8 Percentile:49.02(Geology)Micro-X-ray fluorescence (XRF) scanning spectroscopy of marine and lake sedimentary sequences can provide detailed paleoenvironmental records available through element intensities proxy data. However, problems for effects of interstitial pore water on the micro-XRF intensities have been pointed out so far because of direct measurement on the split wet sediment surfaces. In this study, new methods for the XRF corrections were developed by being considered with the micro-X-ray scanning spectroscopy.
Katsuta, Nagayoshi*; Ikeda, Hisashi*; Shibata, Kenji*; Kokubu, Yoko; Murakami, Takuma*; Tani, Yukinori*; Takano, Masao*; Nakamura, Toshio*; Tanaka, Atsushi*; Naito, Sayuri*; et al.
Global and Planetary Change, 164, p.11 - 26, 2018/05
Times Cited Count:11 Percentile:42.54(Geography, Physical)Paleoenvironmental and paleoclimate changes in Siberia were reconstructed by continuous, high-resolution records of chemical compositions from a sediment core retrieved from the Buguldeika Saddle, Lake Baikal, dating back to the last 33 cal. ka BP. The Holocene climate followed by a shift at ca. 6.5 cal. ka BP toward warm and dry, suggesting that the climate system transition from the glacial to interglacial state occurred. In the last glacial period, the deposition of carbonate mud from the Primorsky Range was associated with Heinrich events (H3 and H1) and the Selenga River inflow was caused by meltwater of mountain glaciers in the Khamar-Daban Range. The anoxic bottom-water during Allerod-Younger Dryas was probably a result of weakened ventilation associated with reduced Selenga River inflow and microbial decomposition of organic matters from the Primorsky Range. The rapid decline in precipitation during the early Holocene may have been a response to the 8.2 ka cooling event.
Yoshida, Hidekazu; Yamamoto, Koshi*; Amano, Yuki; Katsuta, Nagayoshi*; Hayashi, Toru*; Naganuma, Takeshi
Environmental Geology, 55(6), p.1363 - 1374, 2008/09
Times Cited Count:10 Percentile:28.79(Environmental Sciences)Takashikozo is a phenomenon of Quaternary sediments in Japan. They are cylindrical Fe-oxyhydroxide nodules that form as plaques round plant roots. Structural features suggest that after the roots have decayed, the central space where the roots were situated acts as a flow path for oxidized water. Analysis of microbial 16S rDNA extracted from the nodules identified iron-oxidizing bacteria encrusted round the roots where they are the likely initiators of nodule formation. Geological history and nanofossil evidence suggest that these Fe-nodules may have been buried at a depth of up to several tens of meters for a least 100000 years in reducing Quaternary sediments. Thus Fe-oxyhydroxide nodules with water and rock by microbial mediation can persist under reducing conditions. The phenomenon is significant as an analogue of post-closure conditions in radioactive waste repositories, since it could influence nuclide migration.
Masuki, Yuma*; Katsuta, Nagayoshi*; Niwa, Masakazu; Yoshimizu, Chikage*; Tayasu, Ichiro*
no journal, ,
In this presentation, we reported the results of stable carbon, nitrogen, and sulfur isotope analyses for lacustrine sediments formed by the sector-collapse in Mt. Ibuki, Shiga Prefecture.
Masuki, Yuma*; Katsuta, Nagayoshi*; Niwa, Masakazu; Naito, Sayuri*; Yoshimizu, Chikage*; Tayasu, Ichiro*
no journal, ,
In this presentation, we report origin of high arsenic concentration in paleo-dammed lake sediments in Ane River, central Japan.
Itayama, Yui*; Masuki, Yuma*; Minami, Masayo*; Ochiai, Shinya*; Yoshimizu, Chikage*; Tayasu, Ichiro*; Niwa, Masakazu; Katsuta, Nagayoshi*
no journal, ,
In this presentation, we report the environmental changes using Buir lake sediments in eastern Mongolian Plateau.
Igarashi, Yudai*; Udaanjargal, U.*; Kokubu, Yoko; Watanabe, Takahiro; Hasegawa, Hitoshi*; Niiden, I.*; Katsuta, Nagayoshi*; Davaadorj, D.*; Hasebe, Noriko*
no journal, ,
Lake Olgoy locates in the "Valley of the Gobi lakes" in southern Mongolia, on the southern slope of Khangai Mountain range. The 10.5 m core was collected from Lake Olgoy in the winter of 2017. This study measured quartz OSL, feldspar IRSL and radiocarbon ages. Quartz OSL ages range in 0.60.1 ka to 10.7
2.5 ka, feldspar IRSL in 1.1
0.1 ka to 52.9
5.0 ka and radiocarbon ages in 1.4 ka to 48.6 ka. Based on the comparison of ages by three methods, the age-depth model of the core was proposed. Together with other analytical data from the core, glacier melting events in Khangai Mountains will be discussed.
Igarashi, Yudai*; Udaanjargal, U.*; Kokubu, Yoko; Fujita, Natsuko; Hasegawa, Hitoshi*; Niiden, I.*; Katsuta, Nagayoshi*; Davaadorj, D.*; Hasebe, Noriko*
no journal, ,
Lake Olgoy locates in the "Valley of the Gobi lakes" in southern Mongolia, on the southern slope of Khangai Mountain range. The 10.5m core was collected from Lake Olgoy in the winter of 2017. This study measured quartz OSL, feldspar IRSL and radiocarbon ages. Quartz OSL ages range in 0.60.1 ka to 10.7
2.5 ka, feldspar IRSL in 1.1
0.1 ka to 52.9
5.0 ka and radiocarbon ages in 1.4 ka to 48.6 ka. Based on the comparison of ages by three methods, the age-depth model of the core was proposed. Together with other analytical data from the core, glacier melting events in Khangai Mountains will be discussed.
Ikeda, Hisashi*; Shibata, Kenji; Murakami, Takuma; Kokubu, Yoko; Katsuta, Nagayoshi*
no journal, ,
no abstracts in English
Itayama, Yui*; Hayano, Asuka*; Kamegai, Yushi*; Yasuda, Shiori*; Murakami, Takuma*; Ochiai, Shinya*; Niwa, Masakazu; Katsuta, Nagayoshi*
no journal, ,
In this presentation, we report paleo-environmental changes in the southern region of Lake Baikal by chemical and grain-size analyses for the lake sediment cores.
Masuki, Yuma*; Itayama, Yui*; Minami, Masayo*; Niwa, Masakazu; Yoshimizu, Chikage*; Tayasu, Ichiro*; Katsuta, Nagayoshi*
no journal, ,
In this presentation, we report origin and depositional process of arsenic in lacustrine sediments of Ane River, inferred from the stable isotope ratios and organic elements compositions.
Hayakawa, Tsubasa*; Katsuta, Nagayoshi*; Kokubu, Yoko; Hasebe, Noriko*; Murakami, Takuma; Miyata, Yoshiki*; Hasegawa, Hitoshi*; Nagao, Seiya*; Kawakami, Shinichi*
no journal, ,
no abstracts in English
Yoshida, Hidekazu*; Yamamoto, Koshi*; Maruyama, Ippei*; Asahara, Yoshihiro*; Minami, Masayo*; Shirono, Shinichi*; Hasegawa, Hitoshi*; Katsuta, Nagayoshi*; Nishimoto, Shoji*; Muramiya, Yusuke*; et al.
no journal, ,
no abstracts in English