This case study from the Northern Calcareous Alps demonstrates the utilization of historical mining documents for geomorphological purposes, especially for landslide event documentation. The combination of geomorphological mapping and interpretation of up to 200 years old mining maps of the Ischl salt mine (Austria) revealed the existence of a 500 m long earthflow in an engineering geologically well-investigated area. The CAD-based creation of a polythematic map (surface and subsurface features) led to the conclusion that a prehistoric earthflow has been partly reactivated between 1850 and 1934 due to mining subsidence. The depletion zone of the historical earthflow is situated directly above the major collapse zone of the mine. Reactivation was most likely caused by the lowering of the slope base due to slow development of a subsidence trough within the ductile Haselgebirge Formation. Particularly for engineering geomorphological tasks in post-mining-areas, where subsurface facilities are no longer accessible, a combined approach of historical mining map analysis and geomorphological mapping can be regarded as a promising and cost-effective working concept. Supplementary material: historical ground plans and cross sections which are listed in Tab. 1 are available at: https://doi.org/10.6084/m9.figshare.21740459.v1 Thematic collection: This article is part of the Engineering Geology and Hydrogeology of the Anthropocene collection available at: https://www.lyellcollection.org/topic/collections/engineering-geology-and-hydrogeology-of-the-anthropocene
{"title":"Human-induced reactivation of a dormant earthflow? A geomorphological interpretation of historical mining maps of the Ischl salt mine (Austria)","authors":"H. J. Laimer","doi":"10.1144/qjegh2022-012","DOIUrl":"https://doi.org/10.1144/qjegh2022-012","url":null,"abstract":"This case study from the Northern Calcareous Alps demonstrates the utilization of historical mining documents for geomorphological purposes, especially for landslide event documentation. The combination of geomorphological mapping and interpretation of up to 200 years old mining maps of the Ischl salt mine (Austria) revealed the existence of a 500 m long earthflow in an engineering geologically well-investigated area. The CAD-based creation of a polythematic map (surface and subsurface features) led to the conclusion that a prehistoric earthflow has been partly reactivated between 1850 and 1934 due to mining subsidence. The depletion zone of the historical earthflow is situated directly above the major collapse zone of the mine. Reactivation was most likely caused by the lowering of the slope base due to slow development of a subsidence trough within the ductile Haselgebirge Formation. Particularly for engineering geomorphological tasks in post-mining-areas, where subsurface facilities are no longer accessible, a combined approach of historical mining map analysis and geomorphological mapping can be regarded as a promising and cost-effective working concept.\u0000 \u0000 Supplementary material: historical ground plans and cross sections which are listed in Tab. 1 are available at:\u0000 https://doi.org/10.6084/m9.figshare.21740459.v1\u0000 \u0000 \u0000 Thematic collection:\u0000 This article is part of the Engineering Geology and Hydrogeology of the Anthropocene collection available at:\u0000 https://www.lyellcollection.org/topic/collections/engineering-geology-and-hydrogeology-of-the-anthropocene\u0000","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44950192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Mavroulidou, C. Gray, L. Pantoja-Muñoz, M. Gunn
The stabilization of sulphate-bearing soils with traditional calcium-based stabilisers is not recommended, as reactions between the calcium and sulphates in the presence of water could lead to soil heave. Alternative stabilization methods are therefore required, and this paper proposes innovative alkali-activated cements (AAC), whose use for soil stabilisation and especially sulphate-bearing soils is little researched. To fill this knowledge gap, AAC systems with ground granulated blastfurnace slag precursor and different alkaline activators including commercial lime, wastepaper sludge ash (PSA), potassium hydroxide (KOH) and potassium carbonate (K 2 CO 3 ) were used to treat an artificial sulphate-bearing clay. AAC-treated clay specimens cured for 7 and 28 days respectively were soaked in water for 45 days; their one-dimensional swelling, unconfined compressive strength, pH, and ultrasonic pulse velocity were measured and compared to those of specimens not exposed to water. Material characterisation (SEM-EDS, Raman spectroscopy and FTIR) was performed to attest cementation and detect ettringite. In AAC systems, CaO/Ca(OH) 2 did not lead to specimen heave and damage and developed the highest strengths. Potassium-based activators performed less well but combined PSA-K 2 CO 3 led to strength gain in time. Overall AAC led to higher strengths than lime only or lime and admixtures and show promise as sulphate-bearing soil stabilisers. Thematic collection: This article is part of the Leading to Innovative Engineering Geology Practices collection available at: https://www.lyellcollection.org/topic/collections/leading-to-innovative-engineering-geology-practices
{"title":"An assessment of different alkali-activated cements as stabilisers of sulphate-bearing soils","authors":"M. Mavroulidou, C. Gray, L. Pantoja-Muñoz, M. Gunn","doi":"10.1144/qjegh2022-057","DOIUrl":"https://doi.org/10.1144/qjegh2022-057","url":null,"abstract":"\u0000 The stabilization of sulphate-bearing soils with traditional calcium-based stabilisers is not recommended, as reactions between the calcium and sulphates in the presence of water could lead to soil heave. Alternative stabilization methods are therefore required, and this paper proposes innovative alkali-activated cements (AAC), whose use for soil stabilisation and especially sulphate-bearing soils is little researched. To fill this knowledge gap, AAC systems with ground granulated blastfurnace slag precursor and different alkaline activators including commercial lime, wastepaper sludge ash (PSA), potassium hydroxide (KOH) and potassium carbonate (K\u0000 2\u0000 CO\u0000 3\u0000 ) were used to treat an artificial sulphate-bearing clay. AAC-treated clay specimens cured for 7 and 28 days respectively were soaked in water for 45 days; their one-dimensional swelling, unconfined compressive strength, pH, and ultrasonic pulse velocity were measured and compared to those of specimens not exposed to water. Material characterisation (SEM-EDS, Raman spectroscopy and FTIR) was performed to attest cementation and detect ettringite. In AAC systems, CaO/Ca(OH)\u0000 2\u0000 did not lead to specimen heave and damage and developed the highest strengths. Potassium-based activators performed less well but combined PSA-K\u0000 2\u0000 CO\u0000 3\u0000 led to strength gain in time. Overall AAC led to higher strengths than lime only or lime and admixtures and show promise as sulphate-bearing soil stabilisers.\u0000 \u0000 \u0000 Thematic collection:\u0000 This article is part of the Leading to Innovative Engineering Geology Practices collection available at:\u0000 https://www.lyellcollection.org/topic/collections/leading-to-innovative-engineering-geology-practices\u0000","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47900340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Finlayson, Nikhil Nedumpallile-Vasu, G. Carter, Nicola Dakin, R. Cooper
Shorelines in steep glaciated terrain are focal points for development and can provide important natural corridors for transport (e.g., road, rail). However, the steep subaqueous slopes at nearshore sites present challenging ground conditions, and only in recent decades has the acquisition of continuous high-resolution bathymetric datasets become available to inform investigations. This study investigates a site in Loch Lomond, Scotland, where a reported displacement of 15,000 m 3 of rock fill occurred prior to completion and stabilization of an embankment for the A82 road, during improvement work undertaken in the 1980s. We revisit the area using new multibeam swath bathymetry, shallow sub-bottom seismic data and geomorphological mapping, as well borehole logs from the original ground investigation. The bathymetric and seismic data provide strong evidence for older subaqueous landslide activity at the site. The data indicate that embankment construction was also associated with occurrence of subaqueous landslides, incorporating a total volume of up to 95,000m 3 . The research demonstrates the value of nearshore geophysical datasets in steep glaciated terrain, both for understanding geomorphological response to past shoreline modifications and as part of investigations where future developments (e.g., transport, energy infrastructure) are planned.
{"title":"Subaqueous landslides associated with historic road improvements in steep glaciated terrain, Loch Lomond, western Scotland","authors":"A. Finlayson, Nikhil Nedumpallile-Vasu, G. Carter, Nicola Dakin, R. Cooper","doi":"10.1144/qjegh2022-075","DOIUrl":"https://doi.org/10.1144/qjegh2022-075","url":null,"abstract":"\u0000 Shorelines in steep glaciated terrain are focal points for development and can provide important natural corridors for transport (e.g., road, rail). However, the steep subaqueous slopes at nearshore sites present challenging ground conditions, and only in recent decades has the acquisition of continuous high-resolution bathymetric datasets become available to inform investigations. This study investigates a site in Loch Lomond, Scotland, where a reported displacement of 15,000 m\u0000 3\u0000 of rock fill occurred prior to completion and stabilization of an embankment for the A82 road, during improvement work undertaken in the 1980s. We revisit the area using new multibeam swath bathymetry, shallow sub-bottom seismic data and geomorphological mapping, as well borehole logs from the original ground investigation. The bathymetric and seismic data provide strong evidence for older subaqueous landslide activity at the site. The data indicate that embankment construction was also associated with occurrence of subaqueous landslides, incorporating a total volume of up to 95,000m\u0000 3\u0000 . The research demonstrates the value of nearshore geophysical datasets in steep glaciated terrain, both for understanding geomorphological response to past shoreline modifications and as part of investigations where future developments (e.g., transport, energy infrastructure) are planned.\u0000","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46690550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Christopher M. Yeomans, Hester Claridge, Alexander J.L. Hudson, Robin K. Shail, Cees Willems, Matthew Eyre, Chris Harker
Semi-automated algorithms incorporating multi-sourced datasets into a single analysis are increasingly common, but until now operate at a fixed pixel resolution resulting in multi-sourced methods being limited by the largest input pixel size. Multi-scale lineament detection circumvents this issue and allows increased levels of detail to be captured. We present a semi-automated method using a bottom-up Object-Based Image Analysis approach to map regional lineaments to a high level of detail. The method is applied to onshore light detection and ranging (LiDAR) data and offshore bathymetry around the Land's End Granite (Cornwall, UK). The method uses three different pixel resolutions to extract detailed lineaments across a 700 km 2 area. The granite displays large-scale NW–SE fault zones that are considered analogous to those being targeted as onshore deep geothermal reservoirs (2–5 km in depth). Investigation of the lineaments derived from this study shows along-strike variations from NW–SE orientations within granite to NNW–SSE within slate and reflects structural inheritance of early Variscan structures within Devonian slates. This is furthered by analysing these major structures for reservoir potential. Lineaments proximal to these broadly NW–SE features indicate that a damage zone c. 100–200 m wide is present. These observations provide a preliminary understanding of reservoir characteristics for fault-hosted geothermal systems. Thematic collection: This article is part of the Remote sensing for site investigations on Earth and other planets collection available at: https://www.lyellcollection.org/topic/collections/remote-sensing-for-site-investigations-on-earth-and-other-planets Supplementary material: A description of the OBAI method and additional figures are available at https://doi.org/10.6084/m9.figshare.c.6309629
{"title":"A single multi-scale and multi-sourced semi-automated lineament detection technique for detailed structural mapping with applications to geothermal energy exploration","authors":"Christopher M. Yeomans, Hester Claridge, Alexander J.L. Hudson, Robin K. Shail, Cees Willems, Matthew Eyre, Chris Harker","doi":"10.1144/qjegh2022-051","DOIUrl":"https://doi.org/10.1144/qjegh2022-051","url":null,"abstract":"Semi-automated algorithms incorporating multi-sourced datasets into a single analysis are increasingly common, but until now operate at a fixed pixel resolution resulting in multi-sourced methods being limited by the largest input pixel size. Multi-scale lineament detection circumvents this issue and allows increased levels of detail to be captured. We present a semi-automated method using a bottom-up Object-Based Image Analysis approach to map regional lineaments to a high level of detail. The method is applied to onshore light detection and ranging (LiDAR) data and offshore bathymetry around the Land's End Granite (Cornwall, UK). The method uses three different pixel resolutions to extract detailed lineaments across a 700 km 2 area. The granite displays large-scale NW–SE fault zones that are considered analogous to those being targeted as onshore deep geothermal reservoirs (2–5 km in depth). Investigation of the lineaments derived from this study shows along-strike variations from NW–SE orientations within granite to NNW–SSE within slate and reflects structural inheritance of early Variscan structures within Devonian slates. This is furthered by analysing these major structures for reservoir potential. Lineaments proximal to these broadly NW–SE features indicate that a damage zone c. 100–200 m wide is present. These observations provide a preliminary understanding of reservoir characteristics for fault-hosted geothermal systems. Thematic collection: This article is part of the Remote sensing for site investigations on Earth and other planets collection available at: https://www.lyellcollection.org/topic/collections/remote-sensing-for-site-investigations-on-earth-and-other-planets Supplementary material: A description of the OBAI method and additional figures are available at https://doi.org/10.6084/m9.figshare.c.6309629","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134903476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bioventing is a remediation technology that enhances aerobic biodegradation of petroleum-affected soil in the vadose zone by introducing oxygen to the subsurface. Bioventing was historically considered effective for decreasing petroleum hydrocarbons concentrations in soil but discounted for sites where mobile light non-aqueous phase liquid (LNAPL) accumulated in wells. While the science behind bioventing has not changed, the conceptual understanding of LNAPL depletion processes and framework for evaluating the efficacy of LNAPL remediation technologies has changed markedly since the 1990s. This shift leads to a new perspective on the utility and effectiveness of bioventing compared to other LNAPL remedial alternatives. A case study is used to illustrate that mass depletion by bioventing often outperforms hydraulic recovery over time. Biodegradation processes enhanced by bioventing deplete LNAPL constituents in mobile and residual LNAPL in the LNAPL smear zone, which means that bioventing can address a larger mass of LNAPL and may induce a beneficial composition change. Hydraulic LNAPL recovery technologies only access the mobile LNAPL and do not induce a composition change. Furthermore, for low LNAPL recoverability (transmissivity), bioventing typically uses less energy and produces less waste per unit mass of hydrocarbon removed than hydraulic recovery, making bioventing a more sustainable remedial technology.
{"title":"Bioventing revisited: efficacy of enhanced biodegradation for sites with mobile LNAPL","authors":"Jonathon J. Smith, Steven T. Gaito, B. Koons","doi":"10.1144/qjegh2022-085","DOIUrl":"https://doi.org/10.1144/qjegh2022-085","url":null,"abstract":"Bioventing is a remediation technology that enhances aerobic biodegradation of petroleum-affected soil in the vadose zone by introducing oxygen to the subsurface. Bioventing was historically considered effective for decreasing petroleum hydrocarbons concentrations in soil but discounted for sites where mobile light non-aqueous phase liquid (LNAPL) accumulated in wells. While the science behind bioventing has not changed, the conceptual understanding of LNAPL depletion processes and framework for evaluating the efficacy of LNAPL remediation technologies has changed markedly since the 1990s. This shift leads to a new perspective on the utility and effectiveness of bioventing compared to other LNAPL remedial alternatives.\u0000 A case study is used to illustrate that mass depletion by bioventing often outperforms hydraulic recovery over time. Biodegradation processes enhanced by bioventing deplete LNAPL constituents in mobile and residual LNAPL in the LNAPL smear zone, which means that bioventing can address a larger mass of LNAPL and may induce a beneficial composition change. Hydraulic LNAPL recovery technologies only access the mobile LNAPL and do not induce a composition change. Furthermore, for low LNAPL recoverability (transmissivity), bioventing typically uses less energy and produces less waste per unit mass of hydrocarbon removed than hydraulic recovery, making bioventing a more sustainable remedial technology.","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48759038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Slow-moving, chronically destructive landslides are projected to grow in number globally in response to precipitation increases from climate change, and land disturbances from wildfire, mining, and construction. In the Cincinnati and northern Kentucky metropolitan area, USA, landslides develop in colluvium that covers the steep slopes along the Ohio River and its tributaries. Here we quantify elevation changes in a slow-moving colluvial landslide over 14 years using county-wide lidar, uncrewed aerial vehicle (UAV) structure from motion (SfM) surveys, and a UAV lidar survey. Because the technology and quality differ among surveys, the challenge was to calculate a threshold of detectable change for each survey combination. We introduce two methods, the first uses propagated elevation difference errors, and the second back-calculates the individual survey errors. Thresholds of detection range from ± 0.05 to ± 0.20 m. Record rainfall in 2011 produced the largest vertical changes. Since then, the landslide toe has continued to deform, and the landslide has doubled its width by extending into a previously undisturbed slope. While this study presents a technique to utilize older datasets in combination with modern surveys to monitor slow-moving landslides, it is broadly applicable to other studies where topographic data of differing quality is available.
{"title":"Measuring ground surface elevation changes in a slow-moving colluvial landslide using combinations of regional airborne lidar, UAV lidar, and UAV photogrammetric surveys","authors":"S. Johnson, W. Haneberg, L. Bryson, M. Crawford","doi":"10.1144/qjegh2022-078","DOIUrl":"https://doi.org/10.1144/qjegh2022-078","url":null,"abstract":"Slow-moving, chronically destructive landslides are projected to grow in number globally in response to precipitation increases from climate change, and land disturbances from wildfire, mining, and construction. In the Cincinnati and northern Kentucky metropolitan area, USA, landslides develop in colluvium that covers the steep slopes along the Ohio River and its tributaries. Here we quantify elevation changes in a slow-moving colluvial landslide over 14 years using county-wide lidar, uncrewed aerial vehicle (UAV) structure from motion (SfM) surveys, and a UAV lidar survey. Because the technology and quality differ among surveys, the challenge was to calculate a threshold of detectable change for each survey combination. We introduce two methods, the first uses propagated elevation difference errors, and the second back-calculates the individual survey errors. Thresholds of detection range from ± 0.05 to ± 0.20 m. Record rainfall in 2011 produced the largest vertical changes. Since then, the landslide toe has continued to deform, and the landslide has doubled its width by extending into a previously undisturbed slope. While this study presents a technique to utilize older datasets in combination with modern surveys to monitor slow-moving landslides, it is broadly applicable to other studies where topographic data of differing quality is available.","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45621094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Coal mine waters have been sampled during a reconnaissance study in the East Midlands, South Yorkshire and Tyneside areas of England. Almost all the mine waters had similar δ 18 O and δ 2 H indicating a derivation from Holocene recharge (average -7.9‰ and -54‰, respectively, excluding two outliers). Most mine waters emerging by shallow gravity drainage have dissolved sulphate δ 34 S of < +10‰, suggesting a derivation of sulphate from oxidation of pyrite. Deeper mine waters, pumped from boreholes or shafts tended to be more saline with a dissolved sulphate δ 34 S of >+14‰ and, in two cases, >+30‰. The sulphate in these latter waters cannot be readily explained as deriving from pyrite oxidation. Alternative hypotheses (evaporitic or marine brines, evaporite dissolution, closed-system microbial sulphate reduction) can be invoked as explanations. A more general hypothesis proposes that deep groundwaters / mine waters can be regarded as saline “sinks”, whose sulphate δ 34 S is controlled by a dynamic equilibrium between rates of sulphate mobilisation from various sources and sulphate removal by precipitation or microbial reduction. Supplementary material: https://doi.org/10.6084/m9.figshare.c.6418981
{"title":"Dissolved sulphate δ\u0000 34\u0000 S and the origin of sulphate in coal mine waters; NE England","authors":"D. Banks, A. Boyce","doi":"10.1144/qjegh2022-106","DOIUrl":"https://doi.org/10.1144/qjegh2022-106","url":null,"abstract":"\u0000 Coal mine waters have been sampled during a reconnaissance study in the East Midlands, South Yorkshire and Tyneside areas of England. Almost all the mine waters had similar δ\u0000 18\u0000 O and δ\u0000 2\u0000 H indicating a derivation from Holocene recharge (average -7.9‰ and -54‰, respectively, excluding two outliers). Most mine waters emerging by shallow gravity drainage have dissolved sulphate δ\u0000 34\u0000 S of < +10‰, suggesting a derivation of sulphate from oxidation of pyrite. Deeper mine waters, pumped from boreholes or shafts tended to be more saline with a dissolved sulphate δ\u0000 34\u0000 S of >+14‰ and, in two cases, >+30‰. The sulphate in these latter waters cannot be readily explained as deriving from pyrite oxidation. Alternative hypotheses (evaporitic or marine brines, evaporite dissolution, closed-system microbial sulphate reduction) can be invoked as explanations. A more general hypothesis proposes that deep groundwaters / mine waters can be regarded as saline “sinks”, whose sulphate δ\u0000 34\u0000 S is controlled by a dynamic equilibrium between rates of sulphate mobilisation from various sources and sulphate removal by precipitation or microbial reduction.\u0000 \u0000 \u0000 Supplementary material:\u0000 https://doi.org/10.6084/m9.figshare.c.6418981\u0000","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46765887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guiming Dong, Jianing Li, Wenjie Chen, Juan Tian, Yanhui Wang
Results of pumping test are normally uncertain due to insufficient exploration capability and complex hydrogeological conditions, which poses a question as to how to calculate the range of hydraulic conductivity, if the factors affecting the hydraulic conductivity fluctuate within a range. In this paper, the parameters affecting the hydraulic conductivity were regarded as a range, which is called intervals. From this perspective, three analytical expressions which could quickly calculate the intervals of hydraulic conductivity specifically for unconfined aquifer with single well were derived through Dupuit-Forchheimer formula from three universal expressions. The relative errors of the three expressions were analyzed by comparing them with that of equal interval continuous sampling method (EICSM). The results indicated that on the premise that the absolute value of the relative error of the hydraulic conductivity extremum was controlled within 10%, the maximums and minimums should be calculated by Expression 2 (convex model formula) and Expression 3 (Taylor expansion formula) respectively. They were considered as better choices because the allowable change rate could reach 20% and 10%. At the end of the research, an actual pumping test was introduced to verify the above deduction.
{"title":"Analytic Expressions of Hydraulic Conductivity Intervals for Steady Flow to the Single Pumping Well in Unconfined Aquifer","authors":"Guiming Dong, Jianing Li, Wenjie Chen, Juan Tian, Yanhui Wang","doi":"10.1144/qjegh2022-086","DOIUrl":"https://doi.org/10.1144/qjegh2022-086","url":null,"abstract":"Results of pumping test are normally uncertain due to insufficient exploration capability and complex hydrogeological conditions, which poses a question as to how to calculate the range of hydraulic conductivity, if the factors affecting the hydraulic conductivity fluctuate within a range. In this paper, the parameters affecting the hydraulic conductivity were regarded as a range, which is called intervals. From this perspective, three analytical expressions which could quickly calculate the intervals of hydraulic conductivity specifically for unconfined aquifer with single well were derived through Dupuit-Forchheimer formula from three universal expressions. The relative errors of the three expressions were analyzed by comparing them with that of equal interval continuous sampling method (EICSM). The results indicated that on the premise that the absolute value of the relative error of the hydraulic conductivity extremum was controlled within 10%, the maximums and minimums should be calculated by Expression 2 (convex model formula) and Expression 3 (Taylor expansion formula) respectively. They were considered as better choices because the allowable change rate could reach 20% and 10%. At the end of the research, an actual pumping test was introduced to verify the above deduction.","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43383188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Editorial 2023","authors":"Cherith Moses, John Davis","doi":"10.1144/qjegh2023-004","DOIUrl":"https://doi.org/10.1144/qjegh2023-004","url":null,"abstract":"","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47762548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gravity and Time Domain Electromagnetic (TDEM) methods were used in this study to investigate the subsurface hydrogeology of the carbonate-rock aquifer in Arid Environments (Central Tunisia, Western Mediterranean province). The El Houdh basin can be considered an appropriate case for evaluating the vulnerability of groundwater resources under present-day climate change. The identification of structural context and the discontinuities affecting the Eocene/Campanian-Maastrichtian carbonates is an important key to recognize water recharge/discharge pathways and to develop effective and long-term groundwater exploration strategies. Firstly, we have produced an available residual gravity field using a specific Gaussian filter. Then, we generated derivative maps, Euler deconvolution solutions map and a 3D gravity model to delineate different anomalies and to estimate the depth-to-basement parameter and the subsurface density contrasts. Positive and negative anomalies mapping and 3D gravity modelling divulged that the El Houdh basin is associated with an asymmetric “perched syncline” with a segmentation into NE-SW sub-basins (local negative residual anomalies) separated by NW–SE lineaments. The TDEM survey was calibrated using boreholes to image the karst saturated and Unsaturated Zone and to deduce the Epikarst and Endokarst relationship. Finally, the proposed methodology presents a fast and valuable approach for better management of hydrogeological exploitation. Thematic collection: This article is part of the Climate change and resilience in Engineering Geology and Hydrogeology collection available at: https://www.lyellcollection.org/cc/climate-change-and-resilience-in-engineering-geology-and-hydrogeology
{"title":"Carbonate-rock aquifers in Arid Environments (Central Tunisia, Western Mediterranean province): Gravity and Time Domain Electromagnetic methods Investigations","authors":"Mohamed Hamrouni, H. Gabtni","doi":"10.1144/qjegh2022-121","DOIUrl":"https://doi.org/10.1144/qjegh2022-121","url":null,"abstract":"Gravity and Time Domain Electromagnetic (TDEM) methods were used in this study to investigate the subsurface hydrogeology of the carbonate-rock aquifer in Arid Environments (Central Tunisia, Western Mediterranean province). The El Houdh basin can be considered an appropriate case for evaluating the vulnerability of groundwater resources under present-day climate change. The identification of structural context and the discontinuities affecting the Eocene/Campanian-Maastrichtian carbonates is an important key to recognize water recharge/discharge pathways and to develop effective and long-term groundwater exploration strategies. Firstly, we have produced an available residual gravity field using a specific Gaussian filter. Then, we generated derivative maps, Euler deconvolution solutions map and a 3D gravity model to delineate different anomalies and to estimate the depth-to-basement parameter and the subsurface density contrasts. Positive and negative anomalies mapping and 3D gravity modelling divulged that the El Houdh basin is associated with an asymmetric “perched syncline” with a segmentation into NE-SW sub-basins (local negative residual anomalies) separated by NW–SE lineaments. The TDEM survey was calibrated using boreholes to image the karst saturated and Unsaturated Zone and to deduce the Epikarst and Endokarst relationship. Finally, the proposed methodology presents a fast and valuable approach for better management of hydrogeological exploitation.\u0000 \u0000 Thematic collection:\u0000 This article is part of the Climate change and resilience in Engineering Geology and Hydrogeology collection available at:\u0000 https://www.lyellcollection.org/cc/climate-change-and-resilience-in-engineering-geology-and-hydrogeology\u0000","PeriodicalId":20937,"journal":{"name":"Quarterly Journal of Engineering Geology and Hydrogeology","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47155284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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