Ground water最新文献

Mapping the Hydrogeological Structure of a Small Danish Island Using Transient Electromagnetic Methods. 利用瞬态电磁方法绘制丹麦小岛的水文地质结构图。

Ground water Pub Date : 2024-11-09 DOI: 10.1111/gwat.13452

Paul McLachlan, Mathias Ø Vang, Jesper B Pedersen, Rune Kraghede, Anders V Christiansen

{"title":"Mapping the Hydrogeological Structure of a Small Danish Island Using Transient Electromagnetic Methods.","authors":"Paul McLachlan, Mathias Ø Vang, Jesper B Pedersen, Rune Kraghede, Anders V Christiansen","doi":"10.1111/gwat.13452","DOIUrl":"https://doi.org/10.1111/gwat.13452","url":null,"abstract":"Small island communities often rely on groundwater as their primary source of fresh water. However, the limited land area and high proportion of coastal zones pose unique challenges to groundwater management. A detailed understanding of the subsurface structure can provide valuable insights into aquifer structure, groundwater vulnerability, saltwater intrusion, and the location of water resources. These insights can guide groundwater management strategies, for example, pollution regulation, promotion of sustainable agriculture, establishment of coastal buffer zones, and re-naturalization of land cover. Ordinarily, structural characterization relies on geological mapping and boreholes, however, such approaches can have insufficient spatial resolution to aid groundwater management. In this study, transient electromagnetic (TEM) methods are used to map the subsurface of a small, 13.2 km2, Danish Island. The approach successfully identified two previously unknown paleochannels, where the interface between Quaternary aquifer units and an underlying Paleogene Clay aquiclude had maximum depths of 100 and 160 m below sea level. Before this, the interface was assumed to be 15 to 25 m below sea level: therefore, these paleochannels present substantial potential groundwater resources. Resolving geological heterogeneity within the Quaternary deposits was less successful and future work will focus on addressing these limitations. Nonetheless, in several locations, evidence of saltwater intrusion was observed within the Quaternary units. This work demonstrates how TEM mapping can identify water resources, define aquifer boundaries, and aid water management decisions. Such approaches could be applied in other areas, particularly small islands, where similar groundwater challenges exist.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142635084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Interpreting Step-Drawdown Pumping Test Undergoing Confined-Unconfined Conversion with Well Loss. 解释正在进行封闭-非封闭转换（井损）的阶梯式降压抽水试验。

Ground water Pub Date : 2024-11-04 DOI: 10.1111/gwat.13450

Lu Zhang, Hua Zhao, Ling Wang, Jianmei Liu, Qi Zhu, Na Li, Zhang Wen, Yizhao Wang, Dian Wang

{"title":"Interpreting Step-Drawdown Pumping Test Undergoing Confined-Unconfined Conversion with Well Loss.","authors":"Lu Zhang, Hua Zhao, Ling Wang, Jianmei Liu, Qi Zhu, Na Li, Zhang Wen, Yizhao Wang, Dian Wang","doi":"10.1111/gwat.13450","DOIUrl":"https://doi.org/10.1111/gwat.13450","url":null,"abstract":"The step-drawdown pumping test often experiences a transition from confined to unconfined conditions due to the continuously increasing pumping rate. However, the current well hydraulics model has not accurately interpreted this phenomenon. In this study, we developed an analytical solution to address the confined-unconfined conversion in step-drawdown pumping tests based on Girinskii's potential and superposition theory. Additionally, a field step-drawdown pumping test featuring confined-unconfined conversion was conducted to apply the proposed analytical solution. The particle swarm optimization algorithm was employed to simultaneously estimate multiple parameters. The results demonstrate that the newly proposed solution provides a better fit to the observed drawdown in the pumping well compared to previous models. The hydrogeological parameters (K, S), well loss coefficient (B), and critical time for confined-unconfined conversion (tc) were estimated to be K = 7.15 m/d, S = 6.65 × 10-5, B = 7.48 × 10-6, and tc = 1152 min, respectively. Neglecting the confined-unconfined conversion in step-drawdown pumping tests leads to underestimation of drawdown inside the pumping well due to an overestimation of the aquifer thickness. After the conversion from confined to unconfined conditions, the estimated well loss coefficient decreased by 88% compared to its pre-conversion value. This highlights the necessity of adjusting the well loss coefficient in the step-drawdown pumping test model to account for confined-unconfined conversion. In summary, this study introduces a new method for interpreting parameters in step-drawdown pumping tests and provides field validation for its effectiveness.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142570799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrating ERT and SP Techniques for Characterizing Aquifers and Surface-Groundwater Interactions. 整合 ERT 和 SP 技术，确定含水层和地表-地下水相互作用的特征。

Ground water Pub Date : 2024-10-24 DOI: 10.1111/gwat.13444

Md Lal Mamud, Robert M Holt, Craig J Hickey, Andrew M O'Reilly, Leti T Wodajo, Parsa Bakhtiari Rad, Md Abdus Samad

{"title":"Integrating ERT and SP Techniques for Characterizing Aquifers and Surface-Groundwater Interactions.","authors":"Md Lal Mamud, Robert M Holt, Craig J Hickey, Andrew M O'Reilly, Leti T Wodajo, Parsa Bakhtiari Rad, Md Abdus Samad","doi":"10.1111/gwat.13444","DOIUrl":"https://doi.org/10.1111/gwat.13444","url":null,"abstract":"This study enhances the understanding of riverbank filtration and improves management of the Mississippi River valley alluvial (MRVA) aquifer during a managed aquifer recharge (MAR) pilot project at Shellmound, MS. Using high-resolution electrical resistivity tomography (ERT) and self-potential (SP) geophysical methods, we characterized the heterogeneous MRVA aquifer and monitored groundwater flow near a pumping well. ERT was used to provide detailed spatial characterization, filling gaps left by airborne electromagnetic (AEM) data and soil boring logs, while SP techniques were used to monitor groundwater flow, predict drawdown trends, and investigate surface-groundwater interactions. Results showed that SP signals were influenced by groundwater flow, river infiltration, and water mixing due to pumping disturbance of natural geochemical stratification, with significant river interaction observed after 1 h of pumping. The integration of ERT and SP methods revealed lithologic heterogeneity, explaining greater drawdowns on the northern side of the well and increased flow from the riverside. This comprehensive approach offers valuable insights into aquifer management and sustainability.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142515290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Artesian Wells of Batavia, Dutch East-Indies 1872 to 1878. 1872 至 1878 年荷属东印度群岛巴达维亚的自流井。

Ground water Pub Date : 2024-10-22 DOI: 10.1111/gwat.13449

Paul Whincup, Arjen van Schaijk

引用次数: 0

AquiParameter-A Novel Interactive Web-Based Tool for Statistical Assessment of Hydrogeological Parameters. AquiParameter- 一种基于网络的水文地质参数统计评估互动工具。

Ground water Pub Date : 2024-10-18 DOI: 10.1111/gwat.13448

Héctor Baez-Reyes, Antonio Hernández-Espriú

引用次数: 0

Linked Data-Driven, Physics-Based Modeling of Pumping-Induced Subsidence with Application to Bangkok, Thailand. 关联数据驱动的、基于物理学的抽水诱发沉降建模，并应用于泰国曼谷。

Ground water Pub Date : 2024-10-11 DOI: 10.1111/gwat.13443

Jenny T Soonthornrangsan, Mark Bakker, Femke C Vossepoel

{"title":"Linked Data-Driven, Physics-Based Modeling of Pumping-Induced Subsidence with Application to Bangkok, Thailand.","authors":"Jenny T Soonthornrangsan, Mark Bakker, Femke C Vossepoel","doi":"10.1111/gwat.13443","DOIUrl":"https://doi.org/10.1111/gwat.13443","url":null,"abstract":"Research into land subsidence caused by groundwater withdrawal is hindered by the availability of measured heads, subsidence, and forcings. In this paper, a parsimonious, linked data-driven and physics-based approach is introduced to simulate pumping-induced subsidence; the approach is intended to be applied at observation well nests. Time series analysis using response functions is applied to simulate heads in aquifers. The heads in the clay layers are simulated with a one-dimensional diffusion model, using the heads in the aquifers as boundary conditions. Finally, simulated heads in the layers are used to model land subsidence. The developed approach is applied to the city of Bangkok, Thailand, where relatively short time series of head and subsidence measurements are available at or near 23 well nests; an estimate of basin-wide pumping is available for a longer period. Despite the data scarcity, data-driven time series models at observation wells successfully simulate groundwater dynamics in aquifers with an average root mean square error (RMSE) of 2.8 m, relative to an average total range of 21 m. Simulated subsidence matches sparse (and sometimes very noisy) land subsidence measurements reasonably well with an average RMSE of 1.6 cm/year, relative to an average total range of 5.4 cm/year. Performance is not good at eight out of 23 locations, most likely because basin-wide pumping is not representative of localized pumping. Overall, this study demonstrates the potential of a parsimonious, linked data-driven, and physics-based approach to model pumping-induced subsidence in areas with limited data.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142402469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Close-to-Optimal Discretization Strategy for Pumping Test Numerical Simulation. 用于抽水试验数值模拟的接近最优的离散化策略。

Ground water Pub Date : 2024-09-23 DOI: 10.1111/gwat.13442

Ronny Figueroa, Etienne Bresciani

引用次数: 0

The Effective Vertical Anisotropy of Layered Aquifers. 层状含水层的有效垂直各向异性。

Ground water Pub Date : 2024-08-16 DOI: 10.1111/gwat.13432

Mark Bakker, Bram Bot

{"title":"The Effective Vertical Anisotropy of Layered Aquifers.","authors":"Mark Bakker, Bram Bot","doi":"10.1111/gwat.13432","DOIUrl":"https://doi.org/10.1111/gwat.13432","url":null,"abstract":"Many sedimentary aquifers consist of small layers of coarser and finer material. When groundwater flow in these aquifers is modeled, the hydraulic conductivity may be simulated as homogeneous but anisotropic throughout the aquifer. In practice, the anisotropy factor, the ratio of the horizontal divided by the vertical hydraulic conductivity, is often set to 10. Here, numerical experiments are conducted to determine the effective anisotropy of an aquifer consisting of 400 horizontal layers of which the homogeneous and isotropic hydraulic conductivity varies over two orders of magnitude. Groundwater flow is simulated to a partially penetrating canal and a partially penetrating well. Numerical experiments are conducted for 1000 random realizations of the 400 layers, by varying the sequence of the layers, not their conductivity. It is demonstrated that the effective anisotropy of the homogeneous model is a model parameter that depends on the flow field. For example, the effective anisotropy for flow to a partially penetrating canal differs from the effective anisotropy for flow to a partially penetrating well in an aquifer consisting of the exact same 400 layers. The effective anisotropy also depends on the sequence of the layers. The effective anisotropy values of the 1000 realizations range from roughly 5 to 50 for the considered situations. A factor of 10 represents a median value (a reasonable value to start model calibration for the conductivity variations considered here). The median is similar to the equivalent anisotropy, defined as the arithmetic mean of the hydraulic conductivities divided by the harmonic mean.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141989743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Utility of an Instantaneous Salt Dilution Method for Measuring Streamflow in Headwater Streams. 瞬时盐分稀释法在测量上游溪流中的实用性。

Ground water Pub Date : 2024-08-13 DOI: 10.1111/gwat.13437

Karli M Rogers, Jennifer B Fair, Nathaniel P Hitt, Karmann G Kessler, Zachary A Kelly, Martin Briggs

{"title":"Utility of an Instantaneous Salt Dilution Method for Measuring Streamflow in Headwater Streams.","authors":"Karli M Rogers, Jennifer B Fair, Nathaniel P Hitt, Karmann G Kessler, Zachary A Kelly, Martin Briggs","doi":"10.1111/gwat.13437","DOIUrl":"https://doi.org/10.1111/gwat.13437","url":null,"abstract":"Streamflow records are biased toward large streams and rivers, yet small headwater streams are often the focus of ecological research in response to climate change. Conventional flow measurement instruments such as acoustic Doppler velocimeters (ADVs) do not perform well during low-flow conditions in small streams, truncating the development of rating curves during critical baseflow conditions dominated by groundwater inflow. We revisited an instantaneous solute tracer injection method as an alternative to ADVs based on paired measurements to compare their precision, efficiency, and feasibility within headwater streams across a range of flow conditions. We show that the precision of discharge measurements using salt dilution by slug injection and ADV methods were comparable overall, but salt dilution was more precise during the lowest flows and required less time to implement. Often, headwater streams were at or below the depth threshold where ADV measurements could even be attempted and transects were complicated by coarse bed material and cobbles. We discuss the methodological benefits and limitations of salt dilution by slug injection and conclude that the method could facilitate a proliferation of streamflow observation across headwater stream networks that are highly undersampled compared to larger streams.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141972481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Modeling of Recovery of Moisture from the Unsaturated Zone: A Feasibility Study. 从非饱和带回收水分的数值建模：可行性研究。

Ground water Pub Date : 2024-08-05 DOI: 10.1111/gwat.13436

Amitabha Mukhopadhyay, Adnan Akber, Harish Bhandary

{"title":"Numerical Modeling of Recovery of Moisture from the Unsaturated Zone: A Feasibility Study.","authors":"Amitabha Mukhopadhyay, Adnan Akber, Harish Bhandary","doi":"10.1111/gwat.13436","DOIUrl":"https://doi.org/10.1111/gwat.13436","url":null,"abstract":"Numerical modeling of the recovery of moisture by injecting warm air in the unsaturated zone in a 100 m × 100 m plot of agricultural land in Kuwait, a country located in an arid environment, was conducted to provide \"proof of concept\" of the technique. If technically and economically feasible, it will be a potential additional source of water that could be exploited for farming activities and other uses. The COMSOL software was used to develop the model and, based on the results of the scenario runs, the effects of different hydraulic and operational parameters, including that of well spacing, on moisture recovery were assessed. In general, the results suggested that the recovery should increase with the increase in the hydraulic conductivity of the unsaturated zone, the amount of heat input, and the pressure differential between the unsaturated zone and the well head. Within the period examined (0 to 11 days), the recovery decreases with the increase in the soil moisture content, possibly due to the fall in relative permeability to moisture-rich air with the increased water contents in the pore spaces, although the effects may change over a longer period as water contents decrease with moisture recovery. The moisture recovery from the unsaturated zone through the injection of warm air appears to be a feasible proposition from this study that should be demonstrated through a pilot scale experiment in the field.","PeriodicalId":94022,"journal":{"name":"Ground water","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141891366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0