- 著者
- Liu Yaping Zhou Xun Fang Bin Zhou Haiyan Yamanaka Tsutomu
- 出版者
- Springer
- 雑誌
- Environmental earth sciences (ISSN:18666280)
- 巻号頁・発行日
- vol.66, no.7, pp.1887-1896, 2012-08
- 被引用文献数
- 18 6
The Jifei hot spring emerges in the form of a spring group in the Tibet–Yunnan geothermal zone, southwest of Yunnan Province, China. The temperatures of spring waters range from 35 to 81°C and are mainly of HCO3–Na·Ca type. The total discharge of the hot spring is about 10 L/s. The spring is characterized by its huge travertine terrace with an area of about 4,000 m2 and as many as 18 travertine cones of different sizes. The tallest travertine cone is as high as 7.1 m. The travertine formation and evolution can be divided into three periods: travertine terrace deposition period, travertine cone formation period and death period. The hydrochemical characteristics of the Jifei hot spring was analyzed and compared with a local non-travertine hot spring and six other famous travertine springs. The results indicate that the necessary hydrochemical conditions of travertine and travertine cones deposition in the Jifei area are (1) high concentration of HCO3 − and CO2; (2) about 52.9% deep source CO2 with significantly high PCO2 value; (3) very high milliequivalent percentage of HCO3 − (97.4%) with not very high milliequivalent percentage of Ca2+ (24.4%); and (4) a large saturation index of calcite and aragonite of the hot water.
- 著者
- Liu Yaping Yamanaka Tsutomu
- 出版者
- Elsevier B.V.
- 雑誌
- Journal of hydrology (ISSN:00221694)
- 巻号頁・発行日
- vol.464–465, pp.116-126, 2012-09
- 被引用文献数
- 99 4
Mountain–plain transitional landscapes are especially important as groundwater recharge zones. In this study, the oxygen and hydrogen stable isotopic composition (δ18O and δD) of water and hydrochemical information were employed to quantify contribution ratios of different sources of groundwater recharge in the Ashikaga area of central Japan. The study area is situated between the Ashio Mountains and the Kanto Plain, and the Watarase River flows into the region parallel to the mountain–plain boundary. There was an obvious isotopic altitude effect in and around the study area (−0.25‰ per 100 m for δ18O and −1.7‰ per 100 m for δD), and the isotopic signatures of water from the Watarase River and local precipitation could be clearly distinguished. In addition, it was possible to identify the occurrence of mountain block recharge using hydrochemistry, specifically the chloride ion. End-member mixing analysis using δ values and Cl− concentration revealed spatial variation in the contribution ratios of the river water, mountain block groundwater and local precipitation. Seepage from the Watarase River contributed a significant amount of water to aquifers along its channel. The river-recharged water reached 5 km from the channel in the south (i.e., plain) side and 1.6 km or less in the north (i.e., mountain) side. Remarkable mountain block recharge was observed in the foothills near the axis of the syncline, which has layers of chert and sandstone that likely hinder river channel seepage into the mountain-side aquifers. Major factors controlling the river-water contribution ratio include the distance from the river channel, topography, and hydrogeological settings. The results presented here should facilitate integrated management of groundwater and surface water resources.