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Hydraulics, Hydrology and Environmental Engineering (2023)
Book
Mathias, S. A. (2023). Hydraulics, Hydrology and Environmental Engineering. Springer. https://doi.org/10.1007/978-3-031-41973-7

This textbook provides an excellent resource for engineering and science students to develop basic, intermediate and advanced level skills in hydraulics, hydrology and environmental engineering. Topics include open channel flow, ocean waves, kinemati... Read More about Hydraulics, Hydrology and Environmental Engineering.

Revisiting Salvucci’s Semi-analytical Solution for Bare Soil Evaporation with New Consideration of Vapour Diffusion and Film Flow (2023)
Journal Article
Mathias, S. A., Sander, G. C., Leung, J., & Newall, S. R. (2023). Revisiting Salvucci’s Semi-analytical Solution for Bare Soil Evaporation with New Consideration of Vapour Diffusion and Film Flow. Transport in Porous Media, 147(2), 463-493. https://doi.org/10.1007/s11242-023-01917-5

Bare soil evaporation is controlled by a combination of capillary flow, vapour diffusion and film flow. Relevant analytical solutions mostly assume horizontal flow conditions and ignore gravitational effects. Salvucci (1997) provided a rare example o... Read More about Revisiting Salvucci’s Semi-analytical Solution for Bare Soil Evaporation with New Consideration of Vapour Diffusion and Film Flow.

A simple, efficient, mass-conservative approach to solving Richards' equation (openRE, v1.0) (2023)
Journal Article
Ireson, A. M., Spiteri, R. J., Clark, M. P., & Mathias, S. A. (2023). A simple, efficient, mass-conservative approach to solving Richards' equation (openRE, v1.0). Geoscientific Model Development, 16(2), 659-677. https://doi.org/10.5194/gmd-16-659-2023

A simple numerical solution procedure – namely the method of lines combined with an off-the-shelf ordinary differential equation (ODE) solver – was shown in previous work to provide efficient, mass-conservative solutions to the pressure-head form of... Read More about A simple, efficient, mass-conservative approach to solving Richards' equation (openRE, v1.0).

Numerical investigation on origin and evolution of polygonal cracks on rock surfaces (2022)
Journal Article
Chen, T., Foulger, G. R., Tang, C., Mathias, S. A., & Gong, B. (2022). Numerical investigation on origin and evolution of polygonal cracks on rock surfaces. Engineering Geology, 311, Article 106913. https://doi.org/10.1016/j.enggeo.2022.106913

We studied the formation and evolution mechanism of polygonal cracks on rock surfaces under cooling by modelling meso-damage mechanics, continuum mechanics and thermodynamics. Factors that affect rock surface damage include ambient temperature, litho... Read More about Numerical investigation on origin and evolution of polygonal cracks on rock surfaces.

Effect of H2S content on relative permeability and capillary pressure characteristics of acid gas/brine/rock systems: A review (2022)
Journal Article
Zhang, X., Li, Q., Mathias, S., Zheng, G., & Tan, Y. (2022). Effect of H2S content on relative permeability and capillary pressure characteristics of acid gas/brine/rock systems: A review. Journal of Rock Mechanics and Geotechnical Engineering, 14(6), 2003-2033. https://doi.org/10.1016/j.jrmge.2022.03.014

Geological storage of acid gas has been identified as a promising approach to reduce atmospheric carbon dioxide (CO2) and hydrogen sulfide (H2S) and alleviate public concern resulting from sour gas production. A good understanding of the relative per... Read More about Effect of H2S content on relative permeability and capillary pressure characteristics of acid gas/brine/rock systems: A review.

Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses (2021)
Journal Article
Xu, L., Li, Q., Mathias, S. A., Tan, Y., Yang, D., & Fan, C. (2021). Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses. Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 7(4), Article 93. https://doi.org/10.1007/s40948-021-00289-8

The sealing and structural stability of faults must be considered in many underground engineering endeavours, such as underground energy extraction and CO2 geological storage. In order to simultaneously study the evolution laws of fault sealing and s... Read More about Strain characteristics and permeability evolution of faults under stress disturbance monitoring by fibre bragg grating sensing and pressure pulses.

A Model for the Soil Freezing Characteristic Curve That Represents the Dominant Role of Salt Exclusion (2021)
Journal Article
Amankwah, S., Ireson, A., Maulé, C., Brannen, R., & Mathias, S. (2021). A Model for the Soil Freezing Characteristic Curve That Represents the Dominant Role of Salt Exclusion. Water Resources Research, 57(8), Article e2021WR030070. https://doi.org/10.1029/2021wr030070

The phenomenon of freezing point depression in frozen soils results in the co-existence of ice and liquid water in soil pores at temperatures below 273.15 K (0°C), and is thought to have two causes: (a) capillary and adsorption effects, where the pha... Read More about A Model for the Soil Freezing Characteristic Curve That Represents the Dominant Role of Salt Exclusion.

Pseudospectral methods provide fast and accurate solutions for the horizontal infiltration equation (2021)
Journal Article
Mathias, S. A., & Sander, G. C. (2021). Pseudospectral methods provide fast and accurate solutions for the horizontal infiltration equation. Journal of Hydrology, 598, Article 126407. https://doi.org/10.1016/j.jhydrol.2021.126407

An extremely fast and accurate pseudospectral numerical method is presented, which can be used in inverse methods for estimating soil hydraulic parameters from horizontal infiltration or desorption experiments. Chebyshev polynomial dierentiation in c... Read More about Pseudospectral methods provide fast and accurate solutions for the horizontal infiltration equation.

Transmission loss estimation for ephemeral sand rivers in Southern Africa (2021)
Journal Article
Mathias, S. A., Reaney, S. M., & Kenabatho, P. K. (2021). Transmission loss estimation for ephemeral sand rivers in Southern Africa. Journal of Hydrology, 600, Article 126487. https://doi.org/10.1016/j.jhydrol.2021.126487

Ephemeral sand rivers represent an important water resource in Southern Africa. These rivers only flow for a few days in a year. However, much of this water infiltrates the underlying river bed sediments where it is protected from evaporation and uti... Read More about Transmission loss estimation for ephemeral sand rivers in Southern Africa.

An experimentally validated numerical model for bubble growth in magma (2020)
Journal Article
Coumans, J., Llewellin, E., Wadsworth, F., Humphreys, M., Mathias, S., Yelverton, B., & Gardner, J. (2020). An experimentally validated numerical model for bubble growth in magma. Journal of Volcanology and Geothermal Research, 402, Article 107002. https://doi.org/10.1016/j.jvolgeores.2020.107002

Volcanic eruptions are driven by the growth of gas bubbles in magma. The timing and rate of bubble growth are important because they determine whether enough gas pressure can develop to fragment the melt. Bubbles grow in response to decompression and... Read More about An experimentally validated numerical model for bubble growth in magma.

An experimentally-validated numerical model of diffusion and speciation of water in rhyolitic silicate melt (2020)
Journal Article
Coumans, J. P., Llewellin, E. W., Humphreys, M. C., Nowak, M., Brooker, R. A., Mathias, S. A., & McIntosh, I. M. (2020). An experimentally-validated numerical model of diffusion and speciation of water in rhyolitic silicate melt. Geochimica et Cosmochimica Acta, 276, 219-238. https://doi.org/10.1016/j.gca.2020.02.026

The diffusion of water through silicate melts is a key process in volcanic systems. Diffusion controls the growth of the bubbles that drive volcanic eruptions and determines the evolution of the spatial distribution of dissolved water during and afte... Read More about An experimentally-validated numerical model of diffusion and speciation of water in rhyolitic silicate melt.

Gas diffusion in coal powders is a multi-rate process (2019)
Journal Article
Mathias, S., Dentz, M., & Liu, Q. (2020). Gas diffusion in coal powders is a multi-rate process. Transport in Porous Media, 131, 1037-1051. https://doi.org/10.1007/s11242-019-01376-x

Gas migration in coal is strongly controlled by surface diffusion of adsorbed gas within the coal matrix. Surface diffusion coefficients are obtained by inverse modelling of transient gas desorption data from powdered coals. The diffusion coefficient... Read More about Gas diffusion in coal powders is a multi-rate process.

Storage Coefficients and Permeability Functions for Coal-Bed Methane Production Under Uniaxial Strain Conditions (2019)
Journal Article
Mathias, S. A., Nielsen, S., & Ward, R. L. (2019). Storage Coefficients and Permeability Functions for Coal-Bed Methane Production Under Uniaxial Strain Conditions. Transport in Porous Media, 130(2), 627-636. https://doi.org/10.1007/s11242-019-01331-w

The porosity and permeability of coal change with pore pressure, due to changes in effective stress and matrix swelling due to gas adsorption. Three analytical models to describe porosity and permeability change in this context have been presented in... Read More about Storage Coefficients and Permeability Functions for Coal-Bed Methane Production Under Uniaxial Strain Conditions.

Closed-form equation for subsidence due to fluid production from a cylindrical confined aquifer (2019)
Journal Article
Jayeoba, A., Mathias, S. A., Nielsen, S., Vilarrasa, V., & Bjørnarå, T. I. (2019). Closed-form equation for subsidence due to fluid production from a cylindrical confined aquifer. Journal of Hydrology, 573, 964-969. https://doi.org/10.1016/j.jhydrol.2019.03.041

Ground surface subsidence due to groundwater production is a significant problem. Many attempts have been made to develop analytical models to forecast subsidence rates as a consequence of groundwater production. Previous analytical solutions either... Read More about Closed-form equation for subsidence due to fluid production from a cylindrical confined aquifer.

Capillary processes increase salt precipitation during CO2 injection in saline formations (2018)
Journal Article
Kelly, H. L., & Mathias, S. A. (2018). Capillary processes increase salt precipitation during CO2 injection in saline formations. Journal of Fluid Mechanics, 852, 398-421. https://doi.org/10.1017/jfm.2018.540

An important attraction of saline formations for CO2 storage is that their high salinity renders their associated brine unlikely to be identified as a potential water resource in the future. However, high salinity can lead to dissolved salt precipita... Read More about Capillary processes increase salt precipitation during CO2 injection in saline formations.

Masuda's sandstone core hydrate dissociation experiment revisited (2017)
Journal Article
Hardwick, J., & Mathias, S. (2018). Masuda's sandstone core hydrate dissociation experiment revisited. Chemical Engineering Science, 175, 98-109. https://doi.org/10.1016/j.ces.2017.09.003

Numerical simulation of hydrate dissociation in porous media is important to investigate future hydrate fuel extraction strategies and/or the impacts of climate change on the long-term stability of vulnerable near-surface hydrate deposits. The core-s... Read More about Masuda's sandstone core hydrate dissociation experiment revisited.

Gas venting that bypasses the feather edge of marine hydrate, offshore Mauritania (2017)
Journal Article
Li, A., Davies, R. J., Mathias, S., Yang, J., Hobbs, R., & Wilson, M. (2017). Gas venting that bypasses the feather edge of marine hydrate, offshore Mauritania. Marine and Petroleum Geology, 88, 402-409. https://doi.org/10.1016/j.marpetgeo.2017.08.026

Methane can be released from the vast marine hydrate reservoirs that surround continents into oceans and perhaps the atmosphere. But how these pathways work within the global carbon cycle now and during a warmer world is only partially understood. He... Read More about Gas venting that bypasses the feather edge of marine hydrate, offshore Mauritania.

Analytical solution for clay plug swelling experiments (2017)
Journal Article
Mathias, S., Greenwell, H., Withers, C., Erdogan, A., McElwaine, J., & MacMinn, C. (2017). Analytical solution for clay plug swelling experiments. Applied Clay Science, 149, 75-78. https://doi.org/10.1016/j.clay.2017.07.021

Clay swelling experiments frequently involve monitoring the one-dimensional displacement with time of an initially dry clay plug as it imbibes water from a supply at its base. This article presents a new analytical solution for interpreting such expe... Read More about Analytical solution for clay plug swelling experiments.

Soil moisture data as a constraint for groundwater recharge estimation (2017)
Journal Article
Mathias, S. A., Sorensen, J. P., & Butler, A. P. (2017). Soil moisture data as a constraint for groundwater recharge estimation. Journal of Hydrology, 552, 258-266. https://doi.org/10.1016/j.jhydrol.2017.06.040

Estimating groundwater recharge rates is important for water resource management studies. Modeling approaches to forecast groundwater recharge typically require observed historic data to assist calibration. It is generally not possible to observe gro... Read More about Soil moisture data as a constraint for groundwater recharge estimation.

Methane hydrate recycling offshore of Mauritania probably after the last glacial maximum (2017)
Journal Article
Li, A., Davies, R. J., & Mathias, S. (2017). Methane hydrate recycling offshore of Mauritania probably after the last glacial maximum. Marine and Petroleum Geology, 84, 323-331. https://doi.org/10.1016/j.marpetgeo.2017.04.007

To what extent methane liberated from marine hydrate will enter the ocean during a warmer world is unknown. Although methane release due to hydrate dissociation has been modelled, it is unclear whether or not methane will reach the seafloor during a... Read More about Methane hydrate recycling offshore of Mauritania probably after the last glacial maximum.

A study of non-linearity in rainfall-runoff response using 120 UK catchments (2016)
Journal Article
Mathias, S., McIntyre, N., & Oughton, R. (2016). A study of non-linearity in rainfall-runoff response using 120 UK catchments. Journal of Hydrology, 540, 423-436. https://doi.org/10.1016/j.jhydrol.2016.06.039

This study presents a catchment characteristic sensitivity analysis concerning the non-linearity of rainfall-runoff response in 120 UK catchments. Two approaches were adopted. The first approach involved, for each catchment, regression of a power-law... Read More about A study of non-linearity in rainfall-runoff response using 120 UK catchments.

Approximate solutions for Forchheimer flow during water injection and water production in an unconfined aquifer (2016)
Journal Article
Mathias, S., & Moutsopoulos, K. (2016). Approximate solutions for Forchheimer flow during water injection and water production in an unconfined aquifer. Journal of Hydrology, 538, 13-21. https://doi.org/10.1016/j.jhydrol.2016.03.048

Understanding the hydraulics around injection and production wells in unconfined aquifers associated with rainwater and reclaimed water aquifer storage schemes is an issue of increasing importance. Much work has been done previously to understand the... Read More about Approximate solutions for Forchheimer flow during water injection and water production in an unconfined aquifer.

Simulation of three-component two-phase flow in porous media using method of lines (2016)
Journal Article
Goudarzi, S., Mathias, S., & Gluyas, J. (2016). Simulation of three-component two-phase flow in porous media using method of lines. Transport in Porous Media, 112(1), 1-19. https://doi.org/10.1007/s11242-016-0639-5

Numerical simulation of compositional flow problems commonly involves the use of 1st- or 2nd-order Euler time stepping. Method of lines (MOL), using highly accurate and efficient ODE solvers, is an alternative technique which, although frequently app... Read More about Simulation of three-component two-phase flow in porous media using method of lines.

Comparison of relative permeability–saturation–capillary pressure models for simulation of reservoir CO2 injection (2015)
Journal Article
Oostrom, M., White, M., Porse, S., Krevor, S., & Mathias, S. (2016). Comparison of relative permeability–saturation–capillary pressure models for simulation of reservoir CO2 injection. International Journal of Greenhouse Gas Control, 45, 70-85. https://doi.org/10.1016/j.ijggc.2015.12.013

Constitutive relations between relative permeability (kr), fluid saturation (S), and capillary pressure (Pc) determine to a large extent the distribution of brine and supercritical CO2 (scCO2) during subsurface injection operations. Published numeric... Read More about Comparison of relative permeability–saturation–capillary pressure models for simulation of reservoir CO2 injection.

Impact of maximum allowable cost on CO2 storage capacity in saline formations (2015)
Journal Article
Mathias, S., Gluyas, J., Goldthorpe, W., & Mackay, E. (2015). Impact of maximum allowable cost on CO2 storage capacity in saline formations. Environmental Science and Technology, 49(22), 13510-13518. https://doi.org/10.1021/acs.est.5b02836

Injecting CO2 into deep saline formations represents an important component of many greenhouse gas reduction strategies for the future. A number of authors have posed concern over the thousands of injection wells likely to be needed. However, a more... Read More about Impact of maximum allowable cost on CO2 storage capacity in saline formations.

An irregular feather-edge and potential outcrop of marine gas hydrate along the Mauritanian margin (2015)
Journal Article
Davies, R., Yang, J., Mathias, S., & Hobbs, R. (2015). An irregular feather-edge and potential outcrop of marine gas hydrate along the Mauritanian margin. Earth and Planetary Science Letters, 423, 202-209. https://doi.org/10.1016/j.epsl.2015.04.013

The dissociation of marine hydrate that surrounds continental margins is thought to be an agent for past and future climate change. As the water depth decreases landwards, the base of the hydrate stability zone progressively shallows until hydrate ca... Read More about An irregular feather-edge and potential outcrop of marine gas hydrate along the Mauritanian margin.

Numerical simulation of Forchheimer flow to a partially penetrating well with a mixed-type boundary condition (2015)
Journal Article
Mathias, S., & Wen, Z. (2015). Numerical simulation of Forchheimer flow to a partially penetrating well with a mixed-type boundary condition. Journal of Hydrology, 524, 53-61. https://doi.org/10.1016/j.jhydrol.2015.02.015

This article presents a numerical study to investigate the combined role of partial well penetration (PWP) and non-Darcy effects concerning the performance of groundwater production wells. A finite difference model is developed in MATLAB to solve the... Read More about Numerical simulation of Forchheimer flow to a partially penetrating well with a mixed-type boundary condition.

The late field life of the East Midlands Petroleum Province; a new geothermal prospect? (2015)
Journal Article
Hirst, C., Gluyas, J., & Mathias, S. (2015). The late field life of the East Midlands Petroleum Province; a new geothermal prospect?. Quarterly Journal of Engineering Geology and Hydrogeology, 48(2), 104-114. https://doi.org/10.1144/qjegh2014-072

Modification of existing oilfield infrastructure could deliver a cost-effective way to extend the economic life of depleted onshore oilfields. Naturally warm connate and injection water contained within these fields could be initially co-produced wit... Read More about The late field life of the East Midlands Petroleum Province; a new geothermal prospect?.

A soil moisture accounting-procedure with a Richards' equation-based soil texture-dependent parameterization (2014)
Journal Article
Mathias, S., Skaggs, T., Quinn, S., Egan, N., Finch, L., & Oldham, C. (2015). A soil moisture accounting-procedure with a Richards' equation-based soil texture-dependent parameterization. Water Resources Research, 51(1), 506-523. https://doi.org/10.1002/2014wr016144

Given a time-series of potential evapotranspiration and rainfall data, there are at least two approaches for estimating vertical percolation rates. One approach involves solving Richards' equation (RE) with a plant uptake model. An alternative approa... Read More about A soil moisture accounting-procedure with a Richards' equation-based soil texture-dependent parameterization.

Heat transport and pressure buildup during carbon dioxide injection into depleted gas reservoirs (2014)
Journal Article
Mathias, S., McElwaine, J., & Gluyas, J. (2014). Heat transport and pressure buildup during carbon dioxide injection into depleted gas reservoirs. Journal of Fluid Mechanics, 756, 89-109. https://doi.org/10.1017/jfm.2014.348

In this article, a two-layer vertical equilibrium model for the injection of carbon dioxide into a low-pressure porous reservoir containing methane and water is developed. The dependent variables solved for include pressure, temperature and $\def \xm... Read More about Heat transport and pressure buildup during carbon dioxide injection into depleted gas reservoirs.

Dynamic modelling of a UK North Sea saline formation for CO2 sequestration (2014)
Journal Article
Watson, F., Mathias, S., Daniels, S., Jones, R., Davies, R., Hedley, B., & van Hunen, J. (2014). Dynamic modelling of a UK North Sea saline formation for CO2 sequestration. Petroleum Geoscience, 20(2), 169-185. https://doi.org/10.1144/petgeo2012-072

Preliminary dynamic modelling, using TOUGH2/ECO2N, has been carried out to assess the suitability of a site in the UK North Sea for sequestering CO2. The potential storage site is a previously unused saline formation within the Permian Rotliegend san... Read More about Dynamic modelling of a UK North Sea saline formation for CO2 sequestration.

A pseudospectral approach to the McWhorter and Sunada equation for two-phase flow in porous media with capillary pressure (2013)
Journal Article
Bjørnarå, T., & Mathias, S. (2013). A pseudospectral approach to the McWhorter and Sunada equation for two-phase flow in porous media with capillary pressure. Computational Geosciences, 17(6), 889-897. https://doi.org/10.1007/s10596-013-9360-4

Two well-known mathematical solutions for two-phase flow in porous media are the Buckley–Leverett equation and the McWhorter and Sunada equation (MSE). The former ignores capillary pressure and can be solved analytically. The latter has traditionally... Read More about A pseudospectral approach to the McWhorter and Sunada equation for two-phase flow in porous media with capillary pressure.

A statistical analysis of well production rates from UK oil and gas fields – Implications for carbon capture and storage (2013)
Journal Article
Mathias, S., Gluyas, J., Mackay, E., & Goldthorpe, W. (2013). A statistical analysis of well production rates from UK oil and gas fields – Implications for carbon capture and storage. International Journal of Greenhouse Gas Control, 19, 510-518. https://doi.org/10.1016/j.ijggc.2013.10.012

The number of wells required to dispose of global CO2 emissions by injection into geological formations is of interest as a key indicator of feasible deployment rate, scale and cost. Estimates have largely been driven by forecasts of sustainable inje... Read More about A statistical analysis of well production rates from UK oil and gas fields – Implications for carbon capture and storage.

A Lambert W function solution for estimating sustainable injection rates for storage of CO2 in brine aquifers (2013)
Journal Article
Mathias, S., & Roberts, A. (2013). A Lambert W function solution for estimating sustainable injection rates for storage of CO2 in brine aquifers. International Journal of Greenhouse Gas Control, 17, 546-548. https://doi.org/10.1016/j.ijggc.2013.04.007

It is often of interest to estimate the maximum possible CO2 injection rate for a given maximum pressure buildup and injection duration scenario. Analytical solutions exist to estimate pressure buildup due to constant rate injection for a specified d... Read More about A Lambert W function solution for estimating sustainable injection rates for storage of CO2 in brine aquifers.

Multiple well systems with non-Darcy flow (2013)
Journal Article
Mijic, A., Mathias, S., & LaForce, T. (2013). Multiple well systems with non-Darcy flow. Groundwater, 51(4), 588-596. https://doi.org/10.1111/j.1745-6584.2012.00992.x

Optimization of groundwater and other subsurface resources requires analysis of multiple-well systems. The usual modeling approach is to apply a linear flow equation (e.g., Darcy's law in confined aquifers). In such conditions, the composite response... Read More about Multiple well systems with non-Darcy flow.

On the importance of relative permeability data for estimating CO2 injectivity in brine aquifers (2013)
Journal Article
Mathias, S., Gluyas, J., González Martínez de Miguel, G., Bryant, S., & Wilson, D. (2013). On the importance of relative permeability data for estimating CO2 injectivity in brine aquifers. International Journal of Greenhouse Gas Control, 12, 200-212. https://doi.org/10.1016/j.ijggc.2012.09.017

Performance assessment of possible CO2 storage schemes is often investigated through numerical simulation of the CO2 injection process. An important criterion of interest is the maximum sustainable injection rate. Relevant numerical models generally... Read More about On the importance of relative permeability data for estimating CO2 injectivity in brine aquifers.

Hydraulic fractures: How far can they go? (2012)
Journal Article
Davies, R., Mathias, S., Moss, J., Hustoft, S., & Newport, L. (2012). Hydraulic fractures: How far can they go?. Marine and Petroleum Geology, 37(1), 1-6. https://doi.org/10.1016/j.marpetgeo.2012.04.001

The maximum reported height of an upward propagating hydraulic fracture from several thousand fracturing operations in the Marcellus, Barnett, Woodford, Eagle Ford and Niobrara shale (USA) is ∼588 m. Of the 1170 natural hydraulic fracture pipes image... Read More about Hydraulic fractures: How far can they go?.

Deepwater canyons: An escape route for methane sealed by methane hydrate (2012)
Journal Article
Davies, R., Thatcher, K., Mathias, S., & Yang, J. (2012). Deepwater canyons: An escape route for methane sealed by methane hydrate. Earth and Planetary Science Letters, 323-324, 72-78. https://doi.org/10.1016/j.epsl.2011.11.007

Three-dimensional seismic imaging and modelling of gas hydrates from offshore of west Africa (Mauritania) shows that submarine canyons on stable continental slopes can capture and release methane that is sealed by methane hydrate. We demonstrate this... Read More about Deepwater canyons: An escape route for methane sealed by methane hydrate.

Role of partial miscibility on pressure buildup due to constant rate injection of CO2 into closed and open brine aquifers (2011)
Journal Article
Mathias, S., Gluyas, J., González Martínez de Miguel, G., & Hosseini, S. (2011). Role of partial miscibility on pressure buildup due to constant rate injection of CO2 into closed and open brine aquifers. Water Resources Research, 47(12), Article W12525. https://doi.org/10.1029/2011wr011051

[1] This work extends an existing analytical solution for pressure buildup because of CO2 injection in brine aquifers by incorporating effects associated with partial miscibility. These include evaporation of water into the CO2 rich phase and dissolu... Read More about Role of partial miscibility on pressure buildup due to constant rate injection of CO2 into closed and open brine aquifers.

Nitrate pollution in intensively farmed regions: What are the prospects for sustaining high-quality groundwater? (2011)
Journal Article
Howden, N., Burt, T., Worrall, F., Mathias, S., & Whelan, M. (2011). Nitrate pollution in intensively farmed regions: What are the prospects for sustaining high-quality groundwater?. Water Resources Research, 47(6), Article W00L02. https://doi.org/10.1029/2011wr010843

[1] Widespread pollution of groundwater by nutrients due to 20th century agricultural intensification has been of major concern in the developed world for several decades. This paper considers the River Thames catchment (UK), where water-quality moni... Read More about Nitrate pollution in intensively farmed regions: What are the prospects for sustaining high-quality groundwater?.

A trigonometric interpolation approach to mixed-type boundary problems associated with permeameter shape factors (2011)
Journal Article
Klammler, H., Hatfield, K., Nemer, B., & Mathias, S. (2011). A trigonometric interpolation approach to mixed-type boundary problems associated with permeameter shape factors. Water Resources Research, 47(3), Article W03510. https://doi.org/10.1029/2010wr009337

[1] Hydraulic conductivity is a fundamental hydrogeological parameter, whose in situ measurement at a local scale is principally performed through injection tests from screened probes or using impermeable packers in screened wells. The shape factor F... Read More about A trigonometric interpolation approach to mixed-type boundary problems associated with permeameter shape factors.

Analytical solution for Joule-Thomson cooling during CO2 geosequestration in depleted oil and gas reservoirs (2010)
Journal Article
Mathias, S., Gluyas, J., Oldenburg, C., & Tsang, C. (2010). Analytical solution for Joule-Thomson cooling during CO2 geosequestration in depleted oil and gas reservoirs. International Journal of Greenhouse Gas Control, 4(5), 806-810. https://doi.org/10.1016/j.ijggc.2010.05.008

Mathematical tools are needed to screen out sites where Joule–Thomson cooling is a prohibitive factor for CO2 geo-sequestration and to design approaches to mitigate the effect. In this paper, a simple analytical solution is developed by invoking stea... Read More about Analytical solution for Joule-Thomson cooling during CO2 geosequestration in depleted oil and gas reservoirs.