Browsing by Author "Zhao, Jichang"

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    Impact of Xiaolangdi Reservoir on the Evolution of Water Infiltration Influence Zones of the Secondary Perched Reach of the Lower Yellow River
    (MDPI AG, 2023) Zhang, Min; Ping, Jianhua; Zou, Yafei; Li, He; Mahwa, Joshua; Zhao, Jichang; Liu, Jiaqi
    Understanding the complex interplay between water management infrastructure and groundwater dynamics is crucial for sustainable resource utilization. This study investigates water infiltration dynamics in the secondary perched reach of the Yellow River after the operation of the Xiaolangdi Reservoir. The methodology included the application of the single-factor analysis of variance and water balance method, alongside a dual-structure, one-dimensional seepage model to simulate interactions within the system, while exploring characteristics of the groundwater flow system and the exploitation depth of below 100 m. Furthermore, we studied the influence zone range and alterations in river water infiltration in the secondary perched reach of the river following the operation of Xiaolangdi Reservoir. The results show that before the operation of the reservoir, the influence ranges of the north and south banks of the aboveground reach extended from 20.13 km to 20.48 km and 15.85 km to 16.13 km, respectively. Following the initiation of the reservoir, the river channel underwent scouring, leading to enhanced riverbed permeability. Additionally, the influence of long-term groundwater exploitation on both riverbanks extended the influence range of groundwater recharge within the secondary perched reach of the river. The influence zone of the north bank is now 23.41 km–26.74 km and the south bank 18.43 km–21.05 km. After years of shallow groundwater extraction, multiple groundwater depression cones emerged within the five major groundwater source areas on both sides of the river. Notably, deeper water levels (Zhengzhou to Kaifeng) have significantly decreased, with a drop of 42 m to 20 m to 15 m. This change in groundwater dynamics extended beyond the main channel of the river, creating a localized shallow groundwater field.
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    Tectonics and hydrogeochemical features of geothermal waters in Tangyin Rift SE Taihang Mountain
    (Elsevier, 2023) Mahwa, Joshua; Ping, Jianhua; Leng, Wei; Zhao, Jichang; Liu, Jiaqi
    Geothermal exploration in the Tangyin rift is gaining very important attention due to the increased demand for electricity and space heating in the Hebi City area. Due to geological and tectonic settings of rifting extension, volcanism and a thin lithosphere, it possesses a considerable amount of geothermal potential. Efforts to replace sporadic coal use with clean energy sources like gas, geothermal and electricity have helped reduce air pollutants brought about by many household activities. The present work conducts in-depth structural analysis, geochemistry (major and trace elements), and stable isotope analyses of geothermal waters in an attempt to decipher their hydrogeochemical evolution and their influence on the geothermal potential of Tangyin rift. Correlation analyses are used to determine the geochemical mechanisms that control the geochemistry of geothermal waters. The results indicate that large faults' deformational model, permeability, fluid transportation, and fluid flow direction are influenced by major faults trending NNE-SSW. Furthermore, the waters are classified into five types of hydrogeochemical: Ca-HCO3, Na-Cl–SO4, Ca-Mg-HCO3, Na-HCO3 and Ca-Cl. The Na-Cl-SO4 waters are connected with the Hebi volcano and ascend directly. Subsurface activities including cold water mixing and water-rock interaction have a higher impact on the region's Ca-HCO3 shallow ground waters. The geothermal system is characterized by convection-dominated geothermal play coupled with volcanism, replenished by meteoric fluids flowing through fractures and faults from Taihang Mountain and affected by CO2-rich waters from deeper levels. The reservoir is defined as immature water by the Giggenbach Na-K-Mg triangular diagram and mineral saturation indices (SI) that estimate an average reservoir temperature of 220 °C. Finally, the conceptual hydrogeological model for the Tangyin rift geothermal system was developed which can be used for studying the target for geothermal energy development.