Article
Environmental Sciences
S. Banusch, M. Somogyvari, M. Sauter, P. Renard, I Engelhardt
Summary: This study presents a method using a stochastic karst simulator to generate a karst conduit network for a highly karstified carbonate aquifer. The generated network geometry is robust and adjustable, and the resulting stochastic conductivity distribution can be used for parameterizing regional karst groundwater models.
WATER RESOURCES RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Flore Rembert, Marie Leger, Damien Jougnot, Linda Luquot
Summary: In this study, we monitored the electrical conductivity of two limestone core samples during controlled dissolution experiments to better understand the mechanisms responsible for conduits formation and develop detection methods for these processes. We found that constrictivity is more affected by calcite dissolution compared to tortuosity, and the characteristic Johnson length is a valuable structural witness of calcite dissolution impact linking electrical and hydrological properties.
HYDROLOGY AND EARTH SYSTEM SCIENCES
(2023)
Article
Environmental Sciences
Xiujie Wu, Zhongyuan Xu, Zexuan Xu, Bill X. Hu
Summary: This study investigates the impact of karst conduit and pumping conditions on the vulnerability and security of coastal karst aquifers. The results show that aquifers with conduits are more susceptible to seawater intrusion at low pumping rates, while both scenarios experience significant salinization at high pumping rates. The discussion offers insights for managing groundwater in coastal karst aquifers, including vulnerability assessment, selection of pumping locations, and determination of pumping rates.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
Ahmet Sener, Ertan Peksen, Irfan Yolcubal
Summary: The combined application of ERT and Square Array Configuration methods revealed the groundwater recharge characteristics of a karst plateau, providing a more comprehensive and reliable interpretation of the data. The study identified fast and slow recharge zones and sensitive regions for groundwater contamination in the karst plateau.
JOURNAL OF APPLIED GEOPHYSICS
(2021)
Review
Engineering, Civil
Michele Alves, Paulo Galvao, Paulo Aranha
Summary: This study analyzed the karst hydrogeological controls and anthropic effects in the depletion of a 1 km(2) lake in Sete Lagoas, Minas Gerais, Brazil. Results show that climate variation and urban-industrial expansion increase water demand in the region, impacting local potentiometric surfaces and the lake water level.
JOURNAL OF HYDROLOGY
(2021)
Article
Environmental Sciences
L. Levy, R. Thalund-Hansen, T. Bording, G. Fiandaca, A. Christiansen, K. Rugge, N. Tuxen, M. Hag, P. L. Bjerg
Summary: This study presents a monitoring tool for imaging the spreading of ZVI and its associated ionic cloud, using cross-borehole time-lapse ERT. The tool provides a spatially complete and rapid image of the remediation cloud distribution. Additionally, the study investigates the benefit of hydraulic conductivity mapping to understand unexpected injection paths.
WATER RESOURCES RESEARCH
(2022)
Article
Environmental Sciences
Ana Cristina Gonzalez-Valoys, Miguel Vargas-Lombardo, Raimundo Jimenez-Ballesta, Jonatha Arrocha, Eric Gutierrez, Efren Garcia-Ordiales, Pablo Cienfuegos, Francisco Jesus Garcia-Navarro, Pablo Higueras
Summary: The supply of water to populations has become increasingly threatened due to climate change, making the search for alternative water sources essential. This study characterizes the soil and rock hosting the aquifer in order to gather more information for possible exploitation as a drinking water source. The results show a correlation between the properties of the soil and rock and the quality of the aquifer water.
ENVIRONMENTAL EARTH SCIENCES
(2022)
Article
Chemistry, Multidisciplinary
Zihan Yan, Xiaoming Song, Yuhui Wu, Cuiping Gao, Yunlong Wang, Yuesuo Yang
Summary: The refined characterization of groundwater pollution is crucial for effective remediation. In this study, a high-resolution survey was conducted using non-invasive geophysical sensing technology at a contaminated site in a pesticide factory. Modern electrical resistivity tomography (ERT) technology was employed to rapidly identify and characterize the plumes of organochlorine pesticides in groundwater. The results were highly consistent with borehole sampling and hydrochemical analysis, confirming the high feasibility and accuracy of the refined ERT method to characterize the spatial distribution of pesticide plumes in groundwater.
APPLIED SCIENCES-BASEL
(2022)
Article
Geochemistry & Geophysics
Dana Sirota, Jeffrey Shragge, Richard Krahenbuhl, Andrei Swidinsky, Nicaise Yalo, John Bradford
Summary: This article introduces a low-cost geophysical instrument and develops a modular data logging system to improve its functionality and usability. Numerical modeling and field testing demonstrate the system's robustness in diverse geological environments. The instrument was successfully tested in Benin, showing that the low-cost equipment can be used alongside commercial devices to acquire hydrostratigraphy data.
Article
Construction & Building Technology
Fei Xue, Minjun Cai, Tianzuo Wang, Tongyang Zhao
Summary: This study presents a synthetic method to evaluate the collapse risk of karst caves before subway tunnel construction, with a case study of the Yang-Jian interval tunnel. Through crosshole seismic CT integrated with geological drilling, the karst location and its scale were accurately delineated. Numerical models were built and calculated to investigate the effect of different sizes and locations of karst caves on tunnel stability, leading to the establishment of a disturbance degree evaluation index for quantitative risk assessment. The results suggest that the burial depth of karst caves greatly affects the disturbance degree, and for caves closer to the tunnel, they must be filled to eliminate collapse risk.
ADVANCES IN CIVIL ENGINEERING
(2021)
Article
Environmental Sciences
Jian Zhang, Colette Sirieix, Dominique Genty, Fabien Salmon, Cecile Verdet, Sylvain Mateo, Shan Xu, Stephane Bujan, Ludovic Devaux, Marie Larcanche
Summary: The hydrodynamics of karst terrain are highly complex due to the diverse fractures and reservoirs within limestone formations. 2D time-lapse electrical resistivity tomography (ERT) provides an effective method for studying the relationships between hydrological and geophysical features in karst topography. Using ERT, specific karstic zones such as cave galleries, water storage reservoirs, and wetting fronts can be visualized, and spatial and seasonal variations in resistivity can be captured. The analysis revealed a close seasonal relationship between water excess and resistivity variations, with time delays increasing with depth. Karst reservoirs displayed sensitivity to changes in water excess but were primarily affected by fluctuations in water conductivity.
SCIENCE OF THE TOTAL ENVIRONMENT
(2024)
Article
Water Resources
Muhammad Tayyab Sohail, Asrar Hussan, Muhsan Ehsan, Nadhir Al-Ansari, Malik Muhammad Akhter, Zaira Manzoor, Ahmed Elbeltagi
Summary: Groundwater depletion is an emerging problem worldwide due to climate change and urbanization. This study focuses on two significant water-bearing formations near Karachi, Pakistan. The research reveals an imbalance between groundwater inflow and outflow, resulting in a deficit of groundwater. The oscillation of groundwater levels over the past two decades and the projected decline in the future raise concerns about the sustainability of groundwater resources.
APPLIED WATER SCIENCE
(2022)
Article
Geochemistry & Geophysics
Alex Miltenberger, Sebastian Uhlemann, Tapan Mukerji, Ken Williams, Baptiste Dafflon, Lijing Wang, Haruko Wainwright
Summary: As climate changes and populations grow, groundwater sustainability becomes more crucial. Hydrogeologic models are important tools for decision-making, but a common issue arises when multiple geological phenomena could explain a single subsurface parameterization.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Geosciences, Multidisciplinary
[Anonymous]
Summary: A geophysical survey using electrical resistivity imaging was conducted in different parts of Perak state, Malaysia to assess the risk of establishing engineering structures in a karst system. The study emphasized the significance of geophysical surveys in properly assessing subsurface physical properties for foundation investigation.
PHYSICS AND CHEMISTRY OF THE EARTH
(2023)
Article
Environmental Sciences
Portia Mokoena, Kinsley Manyama, Jan van Bever Donker, Thokozani Kanyerere
Summary: Seawater intrusion is a major factor impacting groundwater quality in coastal aquifers. A resistivity imaging survey using the Wenner Array system revealed areas of saline groundwater, brackish formation, and freshwater saturated layers. Geochemical analysis showed high salinity, indicating that overall groundwater quality is not suitable for human consumption and some locations are impacted by seawater intrusion.
ENVIRONMENTAL EARTH SCIENCES
(2021)
Article
Geosciences, Multidisciplinary
Junfeng Zhu, Thomas M. Parris, Charles J. Taylor, Steven E. Webb, Bart Davidson, Richard Smath, Stephen D. Richardson, Lisa J. Molofsky, Jenna S. Kromann, Ann P. Smith
Article
Geosciences, Multidisciplinary
Junfeng Zhu, Thomas M. Parris, Charles J. Taylor, Steven E. Webb, Bart Davidson, Richard Smath, Stephen D. Richardson, Lisa J. Molofsky, Jenna S. Kromann, Ann P. Smith
Article
Soil Science
Javier Reyes, Ole Wendroth, Christopher Matocha, Junfeng Zhu, Wei Ren, A. D. Karathanasis
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL
(2018)
Article
Geosciences, Multidisciplinary
Ashley M. Bandy, Kimberly Cook, Alan E. Fryar, Junfeng Zhu
Article
Agronomy
Saadi Sattar Shahadha, Ole Wendroth, Junfeng Zhu, Jason Walton
AGRICULTURAL WATER MANAGEMENT
(2019)
Article
Geosciences, Multidisciplinary
Xi Zhang, Ole Wendroth, Christopher Matocha, Junfeng Zhu, Javier Reyes
Article
Engineering, Civil
Junfeng Zhu, Adam M. Nolte, Nathan Jacobs, Ming Ye
JOURNAL OF HYDROLOGY
(2020)
Article
Engineering, Civil
Nabil Al Aamery, Ethan Adams, James Fox, Admin Husic, Junfeng Zhu, Morgan Gerlitz, Carmen Agouridis, Leonie Bettel
Summary: This study developed a combined discrete-continuum fluviokarst numerical model and applied it to the Cane Run-Royal Spring basin in Kentucky, USA. Multi-objective calibration improved the representation of stream-cave connectivity, but was computationally expensive. Results provided evidence of a mature fluviokarst basin with a well-defined fracture-conduit network and phreatic aquifer.
JOURNAL OF HYDROLOGY
(2021)
Article
Engineering, Geological
Matthew M. Crawford, Jason M. Dortch, Hudson J. Koch, Ashton A. Killen, Junfeng Zhu, Yichaun Zhu, Lindsey S. Bryson, William C. Haneberg
Summary: High-resolution LiDAR data and a detailed landslide inventory were used to develop a combined machine-learning and statistical approach for landslide-susceptibility mapping in Magoffin County, Kentucky. Twelve important geomorphic variables were identified through the use of a random forest classifier and logistic regression. The logistic-regression model had a performance evaluation of 0.83 AUC and was validated with a neighboring landslide inventory.
QUARTERLY JOURNAL OF ENGINEERING GEOLOGY AND HYDROGEOLOGY
(2021)
Article
Astronomy & Astrophysics
Muhammad Usman Rafique, Junfeng Zhu, Nathan Jacobs
Summary: This study used deep learning to directly identify sinkholes from elevation data and aerial imagery. The U-Net image segmentation model was used to locate sinkholes, and four input images of elevation data were used to train the model. The results suggest that deep learning is a viable method for automatically locating sinkholes, with the best performance achieved using DEM gradient data.
EARTH AND SPACE SCIENCE
(2022)
Article
Engineering, Civil
Leonie Bettel, Jimmy Fox, Admin Husic, Junfeng Zhu, Nabil Al Aamery, Tyler Mahoney, Ariel Gold-McCoy
Summary: Karst springs are important drinking water sources, but the routing of contaminants like sediment in karst remains uncertain. Through data collection and modeling, we identified external sediment loading as the primary control of sediment load at springs, contrary to previous assumptions of internal resuspension.
JOURNAL OF HYDROLOGY
(2022)
Article
Green & Sustainable Science & Technology
Shishir K. Sarker, Junfeng Zhu, Alan E. Fryar, Ghulam Jeelani
Summary: Karst springs in the Liddar catchment in northern India were studied to understand their responses to hydrometeorological factors and predict future changes. Statistical time series analysis revealed a moderate karstification and high storage capacity of the karst aquifer, with a memory effect of 43 to 61 days. The machine learning analysis showed that support vector regression outperformed random forest regression in predicting the spring flow, which was found to be more influenced by snow/ice melt than rainfall. The predictions based on climate scenarios indicated an increase in spring flow during late winter to early spring and a decrease in summer and autumn, with further reductions in flow due to increased greenhouse gas emissions.
Article
Soil Science
Xi Zhang, Ole Wendroth, Christopher Matocha, Junfeng Zhu
Article
Environmental Sciences
Xi Zhang, Junfeng Zhu, Ole Wendroth, Christopher Matocha, Dwayne Edwards
VADOSE ZONE JOURNAL
(2019)
Article
Environmental Sciences
Javier Reyes, Ole Wendroth, Christopher Matocha, Junfeng Zhu
VADOSE ZONE JOURNAL
(2019)