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1.	Blunden, Jessica, et al. (författare) State of the climate in 2013 2014 Ingår i: Bulletin of the American Meteorological Society. - 0003-0007. ; 95 Tidskriftsartikel (refereegranskat)abstract © 2014, American Meteorological Society. All rights reserved. In 2013, the vast majority of the monitored climate variables reported here maintained trends established in recent decades. ENSO was in a neutral state during the entire year, remaining mostly on the cool side of neutral with modest impacts on regional weather patterns around the world. This follows several years dominated by the effects of either La Niña or El Niño events. According to several independent analyses, 2013 was again among the 10 warmest years on record at the global scale, both at the Earth’s surface and through the troposphere. Some regions in the Southern Hemisphere had record or near-record high temperatures for the year. Australia observed its hottest year on record, while Argentina and New Zealand reported their second and third hottest years, respectively. In Antarctica, Amundsen-Scott South Pole Station reported its highest annual temperature since records began in 1957. At the opposite pole, the Arctic observed its seventh warmest year since records began in the early 20th century. At 20-m depth, record high temperatures were measured at some permafrost stations on the North Slope of Alaska and in the Brooks Range. In the Northern Hemisphere extratropics, anomalous meridional atmospheric circulation occurred throughout much of the year, leading to marked regional extremes of both temperature and precipitation. Cold temperature anomalies during winter across Eurasia were followed by warm spring temperature anomalies, which were linked to a new record low Eurasian snow cover extent in May. Minimum sea ice extent in the Arctic was the sixth lowest since satellite observations began in 1979. Including 2013, all seven lowest extents on record have occurred in the past seven years. Antarctica, on the other hand, had above-average sea ice extent throughout 2013, with 116 days of new daily high extent records, including a new daily maximum sea ice area of 19.57 million km2 reached on 1 October. ENSO-neutral conditions in the eastern central Pacific Ocean and a negative Pacific decadal oscillation pattern in the North Pacific had the largest impacts on the global sea surface temperature in 2013. The North Pacific reached a historic high temperature in 2013 and on balance the globally-averaged sea surface temperature was among the 10 highest on record. Overall, the salt content in nearsurface ocean waters increased while in intermediate waters it decreased. Global mean sea level continued to rise during 2013, on pace with a trend of 3.2 mm yr-1 over the past two decades. A portion of this trend (0.5 mm yr-1) has been attributed to natural variability associated with the Pacific decadal oscillation as well as to ongoing contributions from the melting of glaciers and ice sheets and ocean warming. Global tropical cyclone frequency during 2013 was slightly above average with a total of 94 storms, although the North Atlantic Basin had its quietest hurricane season since 1994. In the Western North Pacific Basin, Super Typhoon Haiyan, the deadliest tropical cyclone of 2013, had 1-minute sustained winds estimated to be 170 kt (87.5 m s-1) on 7 November, the highest wind speed ever assigned to a tropical cyclone. High storm surge was also associated with Haiyan as it made landfall over the central Philippines, an area where sea level is currently at historic highs, increasing by 200 mm since 1970. In the atmosphere, carbon dioxide, methane, and nitrous oxide all continued to increase in 2013. As in previous years, each of these major greenhouse gases once again reached historic high concentrations. In the Arctic, carbon dioxide and methane increased at the same rate as the global increase. These increases are likely due to export from lower latitudes rather than a consequence of increases in Arctic sources, such as thawing permafrost. At Mauna Loa, Hawaii, for the first time since measurements began in 1958, the daily average mixing ratio of carbon dioxide exceeded 400 ppm on 9 May. The state of these variables, along with dozens of others, and the 2013 climate conditions of regions around the world are discussed in further detail in this 24th edition of the State of the Climate series.
2.	Murray, Christopher J. L., et al. (författare) Population and fertility by age and sex for 195 countries and territories, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017 2018 Ingår i: The Lancet. - 1474-547X .- 0140-6736. ; 392:10159, s. 1995-2051 Tidskriftsartikel (refereegranskat)abstract Background: Population estimates underpin demographic and epidemiological research and are used to track progress on numerous international indicators of health and development. To date, internationally available estimates of population and fertility, although useful, have not been produced with transparent and replicable methods and do not use standardised estimates of mortality. We present single-calendar year and single-year of age estimates of fertility and population by sex with standardised and replicable methods. Methods: We estimated population in 195 locations by single year of age and single calendar year from 1950 to 2017 with standardised and replicable methods. We based the estimates on the demographic balancing equation, with inputs of fertility, mortality, population, and migration data. Fertility data came from 7817 location-years of vital registration data, 429 surveys reporting complete birth histories, and 977 surveys and censuses reporting summary birth histories. We estimated age-specific fertility rates (ASFRs; the annual number of livebirths to women of a specified age group per 1000 women in that age group) by use of spatiotemporal Gaussian process regression and used the ASFRs to estimate total fertility rates (TFRs; the average number of children a woman would bear if she survived through the end of the reproductive age span [age 10–54 years] and experienced at each age a particular set of ASFRs observed in the year of interest). Because of sparse data, fertility at ages 10–14 years and 50–54 years was estimated from data on fertility in women aged 15–19 years and 45–49 years, through use of linear regression. Age-specific mortality data came from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017 estimates. Data on population came from 1257 censuses and 761 population registry location-years and were adjusted for underenumeration and age misreporting with standard demographic methods. Migration was estimated with the GBD Bayesian demographic balancing model, after incorporating information about refugee migration into the model prior. Final population estimates used the cohort-component method of population projection, with inputs of fertility, mortality, and migration data. Population uncertainty was estimated by use of out-of-sample predictive validity testing. With these data, we estimated the trends in population by age and sex and in fertility by age between 1950 and 2017 in 195 countries and territories. Findings: From 1950 to 2017, TFRs decreased by 49·4% (95% uncertainty interval [UI] 46·4–52·0). The TFR decreased from 4·7 livebirths (4·5–4·9) to 2·4 livebirths (2·2–2·5), and the ASFR of mothers aged 10–19 years decreased from 37 livebirths (34–40) to 22 livebirths (19–24) per 1000 women. Despite reductions in the TFR, the global population has been increasing by an average of 83·8 million people per year since 1985. The global population increased by 197·2% (193·3–200·8) since 1950, from 2·6 billion (2·5–2·6) to 7·6 billion (7·4–7·9) people in 2017; much of this increase was in the proportion of the global population in south Asia and sub-Saharan Africa. The global annual rate of population growth increased between 1950 and 1964, when it peaked at 2·0%; this rate then remained nearly constant until 1970 and then decreased to 1·1% in 2017. Population growth rates in the southeast Asia, east Asia, and Oceania GBD super-region decreased from 2·5% in 1963 to 0·7% in 2017, whereas in sub-Saharan Africa, population growth rates were almost at the highest reported levels ever in 2017, when they were at 2·7%. The global average age increased from 26·6 years in 1950 to 32·1 years in 2017, and the proportion of the population that is of working age (age 15–64 years) increased from 59·9% to 65·3%. At the national level, the TFR decreased in all countries and territories between 1950 and 2017; in 2017, TFRs ranged from a low of 1·0 livebirths (95% UI 0·9–1·2) in Cyprus to a high of 7·1 livebirths (6·8–7·4) in Niger. The TFR under age 25 years (TFU25; number of livebirths expected by age 25 years for a hypothetical woman who survived the age group and was exposed to current ASFRs) in 2017 ranged from 0·08 livebirths (0·07–0·09) in South Korea to 2·4 livebirths (2·2–2·6) in Niger, and the TFR over age 30 years (TFO30; number of livebirths expected for a hypothetical woman ageing from 30 to 54 years who survived the age group and was exposed to current ASFRs) ranged from a low of 0·3 livebirths (0·3–0·4) in Puerto Rico to a high of 3·1 livebirths (3·0–3·2) in Niger. TFO30 was higher than TFU25 in 145 countries and territories in 2017. 33 countries had a negative population growth rate from 2010 to 2017, most of which were located in central, eastern, and western Europe, whereas population growth rates of more than 2·0% were seen in 33 of 46 countries in sub-Saharan Africa. In 2017, less than 65% of the national population was of working age in 12 of 34 high-income countries, and less than 50% of the national population was of working age in Mali, Chad, and Niger. Interpretation: Population trends create demographic dividends and headwinds (ie, economic benefits and detriments) that affect national economies and determine national planning needs. Although TFRs are decreasing, the global population continues to grow as mortality declines, with diverse patterns at the national level and across age groups. To our knowledge, this is the first study to provide transparent and replicable estimates of population and fertility, which can be used to inform decision making and to monitor progress. Funding: Bill & Melinda Gates Foundation.
3.	Al-Wardy, W, et al. (författare) Effective stress law for the permeability of clay-rich sandstones 2004 Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 109:4, s. 1-10 Tidskriftsartikel (refereegranskat)abstract Two models of clay-rich sandstones are analyzed to explain the relative sensitivity ofpermeability to pore pressure and confining pressure. In one model the clay lines the entire pore wall in a layer of uniform thickness, and in the second model the clay is distributed in the form of particles that are only weakly coupled to the pore walls. Equations of elasticity and fluid flow are solved for both models, giving expressions for theeffective stress coefficients in terms of clay content and the elastic moduli of the rock andclay. Both models predict that the permeability will be much more sensitive to changes in pore pressure than to changes in confining pressure. The clay particle model gives somewhat better agreement with data from the literature and with new data on a Staintonsandstone having a solid volume fraction of 8% clay.
4.	Liu, Ke, et al. (författare) X Chromosome Dose and Sex Bias in Autoimmune Diseases 2016 Ingår i: Arthritis & Rheumatology. - : WILEY-BLACKWELL. - 2326-5191 .- 2326-5205. ; 68:5, s. 1290-1300 Tidskriftsartikel (refereegranskat)abstract Objective. More than 80% of autoimmune disease predominantly affects females, but the mechanism for this female bias is poorly understood. We suspected that an X chromosome dose effect accounts for this, and we undertook this study to test our hypothesis that trisomy X (47, XXX; occurring in similar to 1 in 1,000 live female births) would be increased in patients with female-predominant diseases (systemic lupus erythematosus [SLE], primary Sjogrens syndrome [SS], primary biliary cirrhosis, and rheumatoid arthritis [RA]) compared to patients with diseases without female predominance (sarcoidosis) and compared to controls. Methods. All subjects in this study were female. We identified subjects with 47, XXX using aggregate data from single-nucleotide polymorphism arrays, and, when possible, we confirmed the presence of 47, XXX using fluorescence in situ hybridization or quantitative polymerase chain reaction. Results. We found 47, XXX in 7 of 2,826 SLE patients and in 3 of 1,033 SS patients, but in only 2 of 7,074 controls (odds ratio in the SLE and primary SS groups 8.78 [95% confidence interval 1.67-86.79], P = 0.003 and odds ratio 10.29 [95% confidence interval 1.18-123.47], P = 0.02, respectively). One in 404 women with SLE and 1 in 344 women with SS had 47, XXX. There was an excess of 47, XXX among SLE and SS patients. Conclusion. The estimated prevalence of SLE and SS in women with 47, XXX was similar to 2.5 and similar to 2.9 times higher, respectively, than that in women with 46, XX and similar to 25 and similar to 41 times higher, respectively, than that in men with 46, XY. No statistically significant increase of 47, XXX was observed in other female-biased diseases (primary biliary cirrhosis or RA), supporting the idea of multiple pathways to sex bias in autoimmunity.
5.	Liu, Ke, et al. (författare) X Chromosome Dose and Sex Bias in Autoimmune Diseases : Increased 47,XXX in Systemic Lupus Erythematosus and Sjögren's Syndrome 2016 Ingår i: Arthritis & Rheumatology. - : Wiley. - 2326-5191 .- 2326-5205. ; 68:5, s. 1290-1300 Tidskriftsartikel (refereegranskat)abstract OBJECTIVE:More than 80% of autoimmune disease is female dominant, but the mechanism for this female bias is poorly understood. We suspected an X chromosome dose effect and hypothesized that trisomy X (47,XXX, 1 in ∼1,000 live female births) would be increased in female predominant diseases (e.g. systemic lupus erythematosus [SLE], primary Sjögren's syndrome [SS], primary biliary cirrhosis [PBC] and rheumatoid arthritis [RA]) compared to diseases without female predominance (sarcoidosis) and controls.METHODS:We identified 47,XXX subjects using aggregate data from single nucleotide polymorphism (SNP) arrays and confirmed, when possible, by fluorescent in situ hybridization (FISH) or quantitative polymerase chain reaction (q-PCR).RESULTS:We found 47,XXX in seven of 2,826 SLE and three of 1,033 SS female patients, but only in two of the 7,074 female controls (p=0.003, OR=8.78, 95% CI: 1.67-86.79 and p=0.02, OR=10.29, 95% CI: 1.18-123.47; respectively). One 47,XXX subject was present for ∼404 SLE women and ∼344 SS women. 47,XXX was present in excess among SLE and SS subjects.CONCLUSION:The estimated prevalence of SLE and SS in women with 47,XXX was respectively ∼2.5 and ∼2.9 times higher than in 46,XX women and ∼25 and ∼41 times higher than in 46,XY men. No statistically significant increase of 47,XXX was observed in other female-biased diseases (PBC or RA), supporting the idea of multiple pathways to sex bias in autoimmunity. This article is protected by copyright. All rights reserved.
6.	Al-Ajmi, Adel M., et al. (författare) A new 3D stability model for the design of non-vertical wellbores 2006 Konferensbidrag (refereegranskat)abstract The Mohr-Coulomb failure criterion is known to be too conservative in estimating the critical mud pressure required to maintain wellbore stability, due to ignoring the strengthening effect of the intermediate principal stress. To eliminate this deficiency, we have developed a new analytical model to estimate the mud pressure required to avoid shear failure at the wall of non-vertical boreholes (i.e., the collapse pressure). This has been achieved by using a linear elastic and isotropic constitutive model for the stresses, and the Mogi-Coulomb criterion to predict failure. For comparison, the stability analysis has been also carried out using Mohr-Coulomb, the modified Lade criterion, and the Drucker-Prager criterion. We have found that implementing the Mogi-Coulomb law instead of Mohr-Coulomb does indeed lessen the conservative nature of the wellbore stability analysis. In general, the Mogi-Coulomb criterion gives an estimate of the collapse pressure that is similar to that given by the modified Lade criterion in polyaxial stress states, and similar to Mohr-Coulomb in triaxial stress states. By comparison, the Drucker-Prager criterion always underestimates the required mud weight. The developed 3D stability model has been applied in a field case study.
7.	Al-ajmi, A.M, et al. (författare) Relation between the Mogi and the Coulomb failure criteria 2005 Ingår i: International Journal of Rock Mechanics And Mining Sciences. - : Elsevier BV. - 1365-1609 .- 1873-4545. ; 42:3, s. 431-439 Tidskriftsartikel (refereegranskat)abstract We have shown that linear Mogi criterion does a good job in representing rock failureunder polyaxial stress states. When σ2 = σ3 the linear version of Mogi's triaxial failurecriterion reduces exactly to the Coulomb criterion. Hence, the linear Mogi criterion can be thought of as a natural extension of the Coulomb criterion into three dimensions (i.e., polyaxial stress space). As Mohr's extension of the Coulomb criterion into three dimensions is often referred to as the Mohr-Coulomb criterion, we propose that the linear version of the Mogi criterion be known as the "Mogi-Coulomb" failure criterion. The classical Coulomb failure criterion can therefore be thought of as a special case, which applies only when σ2 = σ3 of the more general linear Mogi failure criterion. Furthermore, we found that the numerical values of the parameters that appear in the Mogi-Coulombcriterion can be estimated from conventional triaxial test data. Thus, this polyaxial failurecriterion can be applied even in the absence of polyaxial (true triaxial) data. This offers a great advantage, as most laboratories are equipped to conduct only traditional σ2 = σ3tests. Finally, we showed that if the linear form of the Mogi criterion is used, the parameters that appear in it can be unambiguously related to the traditional parameters appearing in the Coulomb failure law. The lack of such a relationship for the parameters appearing in the power-law Mogi criterion has been cited in [8] as a major drawback to the use of that model.
8.	Al-Ajmi, Adel M., et al. (författare) Stability analysis of vertical boreholes using the Mogi-Coulomb failure criterion 2006 Ingår i: International Journal of Rock Mechanics And Mining Sciences. - : Elsevier BV. - 1365-1609 .- 1873-4545. ; 43:8, s. 1200-1211 Tidskriftsartikel (refereegranskat)abstract A main aspect of wellbore stability analysis is the selection of an appropriate rock failure criterion. The most commonly used criterion for brittle failure of rocks is the Mohr-Coulomb criterion. This criterion involves only the maximum and minimum principal stresses, a, and sigma(3), and therefore assumes that the intermediate stress 92 has no influence on rock strength. As the Mohr-Coulomb criterion ignores the strengthening effect of the intermediate stress, it is expected to be too conservative in estimating the critical mud weight required to maintain wellbore stability. Recently, Al-Ajmi and Zimmerman [Relationship between the parameters of the Mogi and Coulomb failure criterion. Int J Rock Mech Min Sci 2005;42(3):431-39.] developed the Mogi-Coulomb failure criterion, and showed that it is reasonably accurate in modelling polyaxial failure data from a variety of rocks. We then develop a model for the stability of vertical boreholes, using linear elasticity theory to calculate the stresses, and the fully-polyaxial Mogi-Coulomb criterion to predict failure. Our model leads to easily computed expressions for the critical mud weight required to maintain wellbore stability.
9.	Al-Marooqi, S.H, et al. (författare) Pore-Scale modelling of NMR relaxation for the characterization of wettability 2006 Ingår i: Journal of Petroleum Science and Engineering. - : Elsevier BV. - 0920-4105 .- 1873-4715. ; 52:1-4, s. 172-186 Tidskriftsartikel (refereegranskat)abstract Several research groups are currently investigating the determination of wettability usingNMR relaxation times. Although correlations with traditional wettability indices have been presented with some success, further effort is needed to relate the wettability atpore-scale to a core-scale measurement of NMR response. For example, a qualitative method using the arithmetic mean of relaxation times at various saturations has been presented [Guan, H., Brougham, D., Sorbie, K.S., Packer, K.J., 2002. Wettability effects in a sandstone reservoir and outcrop cores from NMR relaxation time distributions. J. Petroleum Sci. and Eng. 34, 35-54] and a wettability index that quantifies the amount of surface area that is wetted either by oil or by water, by using the T2 peak at four different saturations has been proposed [Fleury, M., Deflandre, F., 2003. Quantitative evaluation of porous media wettability using NMR relaxometry. Mag. Reson. Imaging 21, 385-387]. Our group at the Imperial College have previously shown experimentally that the T2 distribution provides valuable information about wettability and overall fluid distribution within thepore-space, which is lost if only a single value from the T2 distribution is considered [Al-Mahrooqi, S.H., Grattoni, C.A., Moss, A.K., Jing, X.D., 2003. An investigation of the effect ofwettability on NMR characteristics of sandstone rock and fluid systems. J. Petroleum Sci. and Eng. 39, 389-398]. In this paper we use a simple pore-scale model to understand the effect of wetting and its relationship with NMR relaxation times. The model uses triangular capillary pores with a given pore size distribution. The oil/water distribution within thepores is obtained as a function of capillary pressure and wettability. At a given capillary pressure, the volumes and surface areas of water and oil are calculated for each individual pore. This allows us to calculate the theoretical T2 distribution for that pore size distribution as a function of wettability and saturation. We have used the model to study the T2 distribution for a range of wettabilities and saturations. Results from the model confirmed previous observations from experiments regarding the effect of wettability onNMR T2 distributions. Based on these qualitative results, an improved index for characterising wettability from the T2 distribution has been proposed. We tested the proposed index using NMR T2 data from synthetic and real sandstone core plugs with different wettabilities, ranging from strongly water-wet to strongly oil-wet. Comparison between the proposed index and wettability for the synthetic samples and Amott-Harvey index for core plugs show good correlation.
10.	Al-Yaarubi, A. H., et al. (författare) Navier-Stokes Simulations of Fluid Flow Through a Rock Fracture 2013 Ingår i: Dynamic Fluids and Transport Through in Fractured Rock. - : American Geophysical Union (AGU). - 9781118666173 ; , s. 55-64 Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract A surface profilometer was used to measure fracture profiles every 10 microns over the surfaces of a replica of a fracture in a red Permian sandstone, to within an accuracy of a few microns. These surface data were used as input to two finite element codes that solve the Navier-Stokes equations and the Reynolds equation, respectively. Numerical simulations of flow through these measured aperture fields were carried out at different values of the mean aperture, corresponding to different values of the relative roughness. Flow experiments were also conducted in casts of two regions of the fracture. At low Reynolds numbers, the Navier-Stokes simulations yielded transmissivities for the two fracture regions that were closer to the experimental values than were the values predicted by the lubrication model. In general, the lubrication model overestimated the transmissivity by an amount that varied as a function of the relative roughness, defined as the standard deviation of the aperture divided by the mean aperture. The initial deviations from linearity, for Reynolds numbers in the range 1-10, were consistent with the "weak inertia" model developed by Mei and Auriault for porous media, and with the results obtained computationally by Skjetne et al in 1999 on a two-dimensional self-affine fracture. In the regime 10 < Re < 40, both the computed and measured transmissivities could be fit very well to a Forchheimer-type equation, in which the additional pressure drop varies quadratically with the Reynolds number.
11.	David, E., et al. (författare) Sliding crack model for the uniaxial compression of rock 2007 Ingår i: Proceedings of the 1st Canada-US Rock Mechanics Symposium - Rock Mechanics Meeting Society's Challenges and Demands. - : Taylor & Francis. - 0415444012 - 9780415444019 ; , s. 575-580 Konferensbidrag (refereegranskat)abstract Uniaxial compression tests on rocks, if conducted at stresses below failure, typically show non-linearity in the stress-strain curve, and hysteresis. Walsh (J. Geophys. Res., 1965) explained this behavior in terms of frictional sliding along the faces of closed cracks. Although well known and widely cited, Walsh's model has not previously been developed in sufficient detail to be used for quantitative predictions. We revisit and extend his model, by including the effect of the stress required to close an initially open crack, and we examine the unloading process in detail. Our analysis leads to closed-form expressions for the loading and unloading portions of the stress-strain curve, as functions of elastic modulus of the uncracked rock, the crack density, the characteristic aspect ratio, and the crack friction coefficient. The model provides a good fit to the loading and unloading portions of the stress-strain curves, for experimental data on sandstones taken from the literature.
12.	Ekneligoda, Thushan C., et al. (författare) Boundary perturbation solution for nearly circular holes and rigid inclusions in an infinite elastic medium 2008 Ingår i: Journal of applied mechanics. - : ASME International. - 0021-8936 .- 1528-9036. ; 75:1, s. 011015- Tidskriftsartikel (refereegranskat)abstract The boundary perturbation method is used to solve the problem of a nearly circular rigid inclusion in a two-dimensional elastic medium subjected to hydrostatic stress at infinity. The solution is taken to the fourth order in the small parameter epsilon that quantifies the magnitude of the variation of the radius of the inclusion. This result is then used to find the effective bulk modulus of a body that contains a dilute concentration of such inclusions. The corresponding results for a cavity are obtained by setting the Muskhelishvili coefficient K equal to -1, as specified by the Dundurs correspondence principle. The results for nearly circular pores can be expressed in terms of the pore compressibility. The pore compressibilities given by the perturbation solution are tested against numerical values obtained using the boundary element method, and are shown to have good accuracy over a substantial range of roughness values.
13.	Ekneligoda, Thushan Chandrasiri, et al. (författare) Compressibility of two-dimensional pores having n-fold axes of symmetry 2006 Ingår i: Proceedings of the Royal Society. Mathematical, Physical and Engineering Sciences. - : The Royal Society. - 1364-5021 .- 1471-2946. ; 462:2071, s. 1933-1947 Tidskriftsartikel (refereegranskat)abstract The complex variable method and conformal mapping are used to derive a closed-form expression for the compressibility of an isolated pore in an infinite two-dimensional, isotropic elastic body. The pore is assumed to have an n-fold axis of symmetry, and be represented by at most four terms in the mapping function that conformally maps the exterior of the pore into the interior of the unit circle. The results are validated against some special cases available in the literature, and against boundary-element calculations. By extrapolation of the results for pores obtained from three and four terms of the Schwarz-Christoffel mapping function for regular polygons, the compressibilities of a triangle, square, pentagon and hexagon are found (to at least three digits). Specific results for some other pore shapes, more general than the quasi-polygons obtained from the Schwarz-Christoffel mapping, are also presented. An approximate scaling law for the compressibility, in terms of the ratio of perimeter-squared to area, is also tested. This' expression gives a reasonable approximation to the pore compressibility, but may overestimate it by as much as 20%.
14.	Ekneligoda, Thushan Chandrasiri, 1974- (författare) Estimation of the Elastic Moduli of Porous Materials using Analytical Methods, Numerical Methods, and Image Analysis 2007 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract The effective bulk modulus and effective shear modulus of porous materials having various types of pore shapes are investigated, using both analytical and numerical methods. These solutions, and the scaling laws that are derived with the aid of these solutions, are then used to make predictions of the effective elastic moduli of some sandstones and ceramics, based on two-dimensional images of the pore space. The complex variable method is used to find the hydrostatic and shear compliances of a large family of pores that have N-fold rotational symmetry, and which have at most four terms in their conformal mapping function. This solution is validated using boundary element (BEM) calculations, and is also used to test two scaling laws that estimate the compliances based on the area and perimeter of the pore. The boundary perturbation method is used to study the effect of small-scale roughness on the compressibility and shear compliance of a nominally circular pore. The solution is carried out to fourth order in the roughness parameter for the case of hydrostatic loading, and to second order for shear loading. These solutions allow one to judge the scale of roughness that can safely be ignored when obtaining images of the pores. Predictions are then made of the elastic moduli of some porous materials – two sandstones and a ceramic. Starting with scanning electron micrographs, image analysis software is used to isolate and extract each pore from the host material. The bulk and shear compliances are estimated using both BEM and the two scaling laws. Areally-weighted mean values of these compliances are calculated for each material, and the differential effective medium scheme is used to obtain expressions for the moduli as functions of porosity. These predictions agree well with the experimental values found in the literature.
15.	Ekneligoda, Thushan C., et al. (författare) Shear compliance of two-dimensional pores possessing N-fold axis of rotational symmetry 2008 Ingår i: Proceedings of the Royal Society. Mathematical, Physical and Engineering Sciences. - : The Royal Society. - 1364-5021 .- 1471-2946. ; 464:2091, s. 759-775 Tidskriftsartikel (refereegranskat)abstract We use the complex variable method and conformal mapping to derive a closed-form expression for the shear compliance parameters of some two-dimensional pores in an elastic material. The pores have an N-fold axis of rotational symmetry and can be represented by at most three terms in the mapping function that conformally maps the exterior of the pore into the interior of the unit circle. We validate our results against the solutions of some special cases available in the literature, and against boundary-element calculations. By extrapolation of the results for pores obtained from two and three terms of the Schwarz-Christoffel mapping function for regular polygons, we find the shear compliance of a triangle, square, pentagon and hexagon. We explicitly verify the fact that the shear compliance of a symmetric pore is independent of the orientation of the pore relative to the applied shear, for all cases except pores of fourfold symmetry. We also show that pores having fourfold symmetry, or no symmetry, will have shear compliances that vary with cos 4 theta. An approximate scaling law for the shear compliance parameter, in terms of the ratio of perimeter squared to area, is proposed and tested.
16.	Gei, Maga, et al. (författare) Legume abundance along successional and rainfall gradients in Neotropical forests 2018 Ingår i: Nature Ecology & Evolution. - : Springer Science and Business Media LLC. - 2397-334X. ; 2:7 Tidskriftsartikel (refereegranskat)abstract The nutrient demands of regrowing tropical forests are partly satisfied by nitrogen-fixing legume trees, but our understanding of the abundance of those species is biased towards wet tropical regions. Here we show how the abundance of Leguminosae is affected by both recovery from disturbance and large-scale rainfall gradients through a synthesis of forest inventory plots from a network of 42 Neotropical forest chronosequences. During the first three decades of natural forest regeneration, legume basal area is twice as high in dry compared with wet secondary forests. The tremendous ecological success of legumes in recently disturbed, water-limited forests is likely to be related to both their reduced leaflet size and ability to fix N2, which together enhance legume drought tolerance and water-use efficiency. Earth system models should incorporate these large-scale successional and climatic patterns of legume dominance to provide more accurate estimates of the maximum potential for natural nitrogen fixation across tropical forests.
17.	Grattoni, C.A, et al. (författare) Polymers as relative permeability modifiers : adsorption and the dynamic formation of thick polyacrylamide layers 2004 Ingår i: Journal of Petroleum Science and Engineering. - : Elsevier BV. - 0920-4105 .- 1873-4715. ; 45:3-4, s. 233-245 Tidskriftsartikel (refereegranskat)abstract Water production from oil and gas reservoirs is increasing worldwide. as more reservoirs are becoming mature. In order to control water production, polymers and gels are often injected into the formation to reduce the water permeability. These systems are known as relative permeability modifiers. Although these methods sometimes lead to significant cost savings, and many successful treatments have been reported, a wider application is hindered by the lack of understanding of the basic mechanisms of permeability modification by polymers. This paper presents some pore-level and basic studies on polymers, with the aim of providing a better understanding of these systems. Experiments have been performed in micro-scale glass flow models, and atomic force microscopy was used to validate the flow observations. The role of adsorption and flow of polyacrylamides in the formation of thick layers is described. The size of statically adsorbed polyacrylamide layers depends on the polymer characteristics (molecular weight, degree of hydrolysis, salinity, etc.), but is less than 250 nm for all the systems studied. On the other hand, dynamically formed polymer layers can reach several thousands of nanometres. The existence of these thick polymer layers is shown here, to our knowledge for the first time, through flow experiments and AFM measurements. While mechanical retention cannot occur under our experimental conditions, the mechanism of adsorption-entanglement gives a reasonable mechanistic description of the dynamic formation of thick layers. The implications of these mechanisms in the modelling of the flow and selection of polymer systems are discussed.
18.	Hülsmann, Lisa, et al. (författare) Latitudinal patterns in stabilizing density dependence of forest communities 2024 Ingår i: Nature. - 0028-0836 .- 1476-4687. ; 627, s. 564-571 Tidskriftsartikel (refereegranskat)abstract Numerous studies have shown reduced performance in plants that are surrounded by neighbours of the same species1,2, a phenomenon known as conspecific negative density dependence (CNDD)3. A long-held ecological hypothesis posits that CNDD is more pronounced in tropical than in temperate forests4,5, which increases community stabilization, species coexistence and the diversity of local tree species6,7. Previous analyses supporting such a latitudinal gradient in CNDD8,9 have suffered from methodological limitations related to the use of static data10–12. Here we present a comprehensive assessment of latitudinal CNDD patterns using dynamic mortality data to estimate species-site-specific CNDD across 23 sites. Averaged across species, we found that stabilizing CNDD was present at all except one site, but that average stabilizingCNDD was not stronger toward the tropics. However, in tropical tree communities, rare and intermediate abundant species experienced stronger stabilizing CNDD than did common species. This pattern was absent in temperate forests, which suggests that CNDD influences species abundances more strongly in tropical forests than it does in temperate ones13. We also found that interspecific variation in CNDD, which might attenuate its stabilizing effect on species diversity14,15, was high but not significantly different across latitudes. Although the consequences of these patterns for latitudinal diversity gradients are difficult to evaluate, we speculate that a more effective regulation of population abundances could translate into greater stabilization of tropical tree communities and thus contribute to the high local diversity of tropical forests.
19.	Muscarella, Robert, et al. (författare) A well-resolved phylogeny of the trees of Puerto Rico based on DNA barcode sequence data 2014 Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:11 Tidskriftsartikel (refereegranskat)abstract Background The use of phylogenetic information in community ecology and conservation has grown in recent years. Two key issues for community phylogenetics studies, however, are (i) low terminal phylogenetic resolution and (ii) arbitrarily defined species pools. Methodology/principal findings We used three DNA barcodes (plastid DNA regions rbcL, matK, and trnH-psbA) to infer a phylogeny for 527 native and naturalized trees of Puerto Rico, representing the vast majority of the entire tree flora of the island (89%). We used a maximum likelihood (ML) approach with and without a constraint tree that enforced monophyly of recognized plant orders. Based on 50% consensus trees, the ML analyses improved phylogenetic resolution relative to a comparable phylogeny generated with Phylomatic (proportion of internal nodes resolved: constrained ML = 74%, unconstrained ML = 68%, Phylomatic = 52%). We quantified the phylogenetic composition of 15 protected forests in Puerto Rico using the constrained ML and Phylomatic phylogenies. We found some evidence that tree communities in areas of high water stress were relatively phylogenetically clustered. Reducing the scale at which the species pool was defined (from island to soil types) changed some of our results depending on which phylogeny (ML vs. Phylomatic) was used. Overall, the increased terminal resolution provided by the ML phylogeny revealed additional patterns that were not observed with a less-resolved phylogeny. Conclusions/significance With the DNA barcode phylogeny presented here (based on an island-wide species pool), we show that a more fully resolved phylogeny increases power to detect nonrandom patterns of community composition in several Puerto Rican tree communities. Especially if combined with additional information on species functional traits and geographic distributions, this phylogeny will (i) facilitate stronger inferences about the role of historical processes in governing the assembly and composition of Puerto Rican forests, (ii) provide insight into Caribbean biogeography, and (iii) aid in incorporating evolutionary history into conservation planning.
20.	Piponiot, Camille, et al. (författare) Distribution of biomass dynamics in relation to tree size in forests across the world 2022 Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 234, s. 1664-1677 Tidskriftsartikel (refereegranskat)abstract Tree size shapes forest carbon dynamics and determines how trees interact with their environment, including a changing climate. Here, we conduct the first global analysis of among-site differences in how aboveground biomass stocks and fluxes are distributed with tree size. We analyzed repeat tree censuses from 25 large-scale (4–52 ha) forest plots spanning a broad climatic range over five continents to characterize how aboveground biomass, woody productivity, and woody mortality vary with tree diameter. We examined how the median, dispersion, and skewness of these size-related distributions vary with mean annual temperature and precipitation. In warmer forests, aboveground biomass, woody productivity, and woody mortality were more broadly distributed with respect to tree size. In warmer and wetter forests, aboveground biomass and woody productivity were more right skewed, with a long tail towards large trees. Small trees (1–10 cm diameter) contributed more to productivity and mortality than to biomass, highlighting the importance of including these trees in analyses of forest dynamics. Our findings provide an improved characterization of climate-driven forest differences in the size structure of aboveground biomass and dynamics of that biomass, as well as refined benchmarks for capturing climate influences in vegetation demographic models.
21.	Reusch, Simeon, et al. (författare) Candidate Tidal Disruption Event AT2019fdr Coincident with a High-Energy Neutrino 2022 Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 128:22 Tidskriftsartikel (refereegranskat)abstract The origins of the high-energy cosmic neutrino flux remain largely unknown. Recently, one high-energy neutrino was associated with a tidal disruption event (TDE). Here we present AT2019fdr, an exceptionally luminous TDE candidate, coincident with another high-energy neutrino. Our observations, including a bright dust echo and soft late-time x-ray emission, further support a TDE origin of this flare. The probability of finding two such bright events by chance is just 0.034%. We evaluate several models for neutrino production and show that AT2019fdr is capable of producing the observed high-energy neutrino, reinforcing the case for TDEs as neutrino sources.
22.	Rhodes, Olin E., et al. (författare) Integration of ecosystem science into radioecology : A consensus perspective 2020 Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 740 Tidskriftsartikel (refereegranskat)abstract In the Fall of 2016 a workshop was held which brought together over 50 scientists from the ecological and radiological fields to discuss feasibility and challenges of reintegrating ecosystem science into radioecology. There is a growing desire to incorporate attributes of ecosystem science into radiological risk assessment and radioecological research more generally, fueled by recent advances in quantification of emergent ecosystem attributes and the desire to accurately reflect impacts of radiological stressors upon ecosystem function. This paper is a synthesis of the discussions and consensus of the workshop participant's responses to three primary questions, which were: 1) How can ecosystem science support radiological risk assessment? 2) What ecosystem level endpoints potentially could be used for radiological risk assessment? and 3) What inference strategies and associated methods would be most appropriate to assess the effects of radionuclides on ecosystem structure and function? The consensus of the participants was that ecosystem science can and should support radiological risk assessment through the incorporation of quantitative metrics that reflect ecosystem functions which are sensitive to radiological contaminants. The participants also agreed that many such endpoints exit or are thought to exit and while many are used in ecological risk assessment currently, additional data need to be collected that link the causal mechanisms of radiological exposure to these endpoints. Finally, the participants agreed that radiological risk assessments must be designed and informed by rigorous statistical frameworks capable of revealing the causal inference tying radiological exposure to the endpoints selected for measurement.
23.	Robison Fernlund, Joanne, et al. (författare) Influence of volume/mass on grain-size curves and conversion of image-analysis size to sieve size 2007 Ingår i: Engineering Geology. - : Elsevier BV. - 0013-7952 .- 1872-6917. ; 90:04-mar, s. 124-137 Tidskriftsartikel (refereegranskat)abstract Image analysis of aggregates does not measure the same size as sieve analysis. The size of aggregates, determined by sieve analysis, is presented with respect to the percent cumulative mass, whereas image analysis does not measure mass. Results are often presented in percent particles or percent area. Several researchers have claimed that more accurate volume and mass determinations are necessary for accurate construction of grain-size curves. In the present work, several methods for reconstructing volume and thus mass of aggregates from image analysis (IA) have been tested to see how they influence the grain-size distribution curves. The actual mass of the individual particles was found to have little or no influence on the grain-size distribution curve, which is normalized and thus insensitive to mass. Accurate conversion of image-analysis size to sieve size is dependent upon how particles pass through sieves. Most existing methods base their conversion of image-analysis size to sieve size on the intermediate axis, multiplied by some factor. The present work shows that there is no direct correlation between the intermediate axes and sieve size. A universal conversion of image-analysis size to sieve size has been developed, using the minimum-bounding square around the minimum projected area. This measure yields very good correlation with sieve-analysis results.
24.	Saceanu, M. Cristina, et al. (författare) Fracture growth leading to mechanical spalling around deposition boreholes of an underground nuclear waste repository 2022 Ingår i: International Journal of Rock Mechanics And Mining Sciences. - : Elsevier BV. - 1365-1609 .- 1873-4545. ; 152, s. 105038- Tidskriftsartikel (refereegranskat)abstract This study presents a three-dimensional numerical analysis of multiple fracture growth leading to spalling around nuclear waste deposition boreholes. Mechanical spalling due to stress amplification after drilling is simulated using a finite element-based fracture growth simulator. Fractures initiate in tension based on a damage criterion and grow by evaluating stress intensity factors at each fracture tip. Tip propagation is multi modal, resulting in final fracture patterns that are representative of both tensile and shear failure. Their geometries are represented by smooth parametric surfaces, which evolve during growth using lofting. The corresponding surface and volumetric meshes are updated at every growth step to accommodate the evolving fracture geometries. The numerical model is validated by comparing simulated fracture patterns against those observed in the AECL Underground Rock Laboratory Mine-By Experiment. It is subsequently calibrated to simulate fracture initiation and growth around boreholes drilled in the Forsmark granodiorite, subjected to a far-field anisotropic triaxial stress that corresponds to the in situ stress model from the Swedish Forsmark site. The deposition tunnel is implicitly simulated by attaching the deposition borehole to a free domain boundary.Several geomechanical cases are investigated, in which fracture growth is numerically evaluated as a function of in situ stress state, tunnel orientation, borehole geometry, total number of boreholes and borehole spacing. Numerical results show that spalling occurs in all cases, given the underground conditions at Forsmark, with borehole geometry, spacing and stresses affecting the extent of fracture nucleation and growth patterns.The uncertainty in underground stress conditions is evaluated through varying stress magnitudes and orientations relative to the tunnel floor. Whereas tunnel orientation influences the relative locations where fractures initiate with respect to the tunnel floor, fracture growth and its final extent is determined by the relative magnitudes of the in situ stresses. Higher stress differential causes higher spalling depths, but in all cases, failure extent is localised to the borehole vicinity, not exceeding one borehole radius. The cylindrical borehole is modified at the top to provide an access ramp for the spent fuel canisters and fracture growth around several deposition boreholes is simulated for borehole tops having cylindrical, conical, and wedge shapes. The enlargement of the borehole top induces higher stress concentrations at the borehole-tunnel junction, increasing the severity of spalling closer to the tunnel floor. Massive failure occurs when a multiple borehole model is considered and the inter-borehole distance is small enough that adjacent "spalled"areas interact. At Forsmark, through-going fractures are predicted to develop when the borehole spacing is less than 4 m. The effect of spalling on the structural integrity of the deposition boreholes is illustrated for each test case and quantified in terms of maximum spalling depth, spalling width and total fractured surface area.
25.	Tavassoli, Z, et al. (författare) Analysis of counter-current imbibition with gravity in weakly water-wet systems 2005 Ingår i: Journal of Petroleum Science and Engineering. - : Elsevier BV. - 0920-4105 .- 1873-4715. ; 48:1-2, s. 94-104 Tidskriftsartikel (refereegranskat)abstract Counter-current imbibition in one dimension is analyzed, in which a wetting phase (water) displaces a non-wetting phase against gravity. An approximate analytical approach is used to derive an expression for the saturation profile in the case where the mobility of the displaced phase at the inlet is finite. This approach is applicable to waterflooding in hydrocarbon reservoirs, flow in geothermal systems, or the displacement of non-aqueous phase liquid (NAPL) or air by water. Solutions are developed for both gravity-dominated and capillary-dominated cases. In the capillary-dominated limit the predicted recoveries compare very well with experimental data from the literature, over all time scales. The use of this expression for field-scale dual-porosity modeling of flow in fractured systems is briefly discussed.
26.	Tavassoli, Z., et al. (författare) Analytic analysis for oil recovery during counter-current imbibition in strongly water-wet systems 2005 Ingår i: Transport in Porous Media. - : Springer Science and Business Media LLC. - 0169-3913 .- 1573-1634. ; 58:1-2, s. 173-189 Tidskriftsartikel (refereegranskat)abstract We study counter-current imbibition, where a strongly wetting phase ( water) displaces non-wetting phase spontaneously under the influence of capillary forces such that the non-wetting phase moves in the opposite direction to the water. We use an approximate analytical approach to derive an expression for saturation profile when the viscosity of the non-wetting phase is non-negligible. This makes the approach applicable to water flooding in hydrocarbon reservoirs, or the displacement of non-aqueous phase liquid (NAPL) by water. We find the recovery of non-wetting phase as a function of time for one-dimensional flow. We compare our predictions with experimental results in the literature. Our formulation reproduces experimental data accurately and is superior to previously proposed empirical models.
27.	The Imperial College lectures in petroleum engineering 2018 Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract This book presents, in a self-contained form, the equations of fluid flow in porous media, with a focus on topics and issues that are relevant to petroleum reservoir engineering. No prior knowledge of the field is assumed on the part of the reader, and particular care is given to careful mathematical and conceptual development of the governing equations, and solutions for important reservoir flow problems. Fluid Flow in Porous Media starts with a discussion of permeability and Darcy's law, then moves on to a careful derivation of the pressure diffusion equation. Solutions are developed and discussed for flow to a vertical well in an infinite reservoir, in reservoirs containing faults, in bounded reservoirs, and to hydraulically fractured wells. Special topics such as the dual-porosity model for fractured reservoirs, and fluid flow in gas reservoirs, are also covered. The book includes twenty problems, along with detailed solutions. As part of the Imperial College Lectures in Petroleum Engineering, and based on a lecture series on the same topic, this book provides the introductory information needed for students of the petroleum engineering and hydrology.
28.	Tong, Fuguo, et al. (författare) A 3D FEM simulation of the buffer and buffer-rock interfacebehaviour of the Canister Retrieval Test (CRT) at Äspö HRL : 29 Sep-01Oct 2009, Luxembourg. European Commission 2009 Ingår i: Proceedings Conference of impact of THMC processes on thesafety of underground radioactive waste repositories. Konferensbidrag (refereegranskat)abstract This paper presents a 3D FEM model for simulating the coupled THM behaviour of the buffer and buffer-rock interface behaviour of the Canister Retrieval Test conducted at the Äspö Hard Rock Laboratory, Sweden. The effect of the interface between the canister and buffer was also included. New numerical techniques were developed for more efficient FEM formulation and equation solution, and for modeling saturated or partially saturated water flow, gas flow and heat transfer in buffer and interfaces. The numerical results compare well with the measured data, and the reasonably good agreement between simulated and measured results indicates that the coupled THM processes of buffer material can be accurately predicted by the newly developed THM model and computer code.
29.	Tong, Fuguo, et al. (författare) A fully coupled thermo-hydro-mechanical model for simulating multiphase flow, deformation and heat transfer in buffer material and rock masses 2010 Ingår i: International Journal of Rock Mechanics And Mining Sciences. - : Elsevier BV. - 1365-1609 .- 1873-4545. ; 47:2, s. 205-217 Tidskriftsartikel (refereegranskat)abstract This paper presents a numerical method for modeling coupled thermo-hydro-mechanical processes of geomaterials with multiphase fluid flow. A FEM code has been developed and validated for modeling the behavior of porous geological media, and is equally applicable for modeling coupled THM processes in rocks. The governing equations are based on the theory of mixtures applied to the multiphysics of porous media, considering solid phase deformation, multiphase fluid flow, and heat transport. New numerical techniques have been developed for more efficient FEM formulation and equation solution for modeling saturated or partially saturated water flow, gas flow and heat transfer indeformable porous media, as are commonly encountered in performance and safety assessment of underground radioactive repositories. The code has been validated against an experimental benchmark test, which involves bentonite under laboratory conditions, with good results. Several critical outstanding issues for modeling coupled processes of geomaterials are discussed indepth.
30.	Tong, Fuguo, et al. (författare) An effective thermal conductivity model of geological porous media for coupled thermo-hydro-mechanical systems with multiphase flow 2009 Ingår i: International Journal of Rock Mechanics And Mining Sciences. - : Elsevier BV. - 1365-1609 .- 1873-4545. ; 46:8, s. 1358-1369 Tidskriftsartikel (refereegranskat)abstract The objective of this paper is to present the development of an effective thermal conductivity model for simulation of thermo-hydro-mechanical processes of geological porous media. The Wiener bounds and Hashin-Shtrikman bounds for thermal conductivity of three-phase mixture are introduced first, followed by descriptions of thermal conductivities of gas, water and solid, respectively. The derivation of a new effective thermal conductivity model, in closed form, is then presented. The model considers the combined effects of solid mineral composition, temperature, liquid saturation degree, porosity and pressure on the effective thermal conductivity of porous media, when multiphase flow with phase change is involved. The model strictly obeys the Wiener bounds (for anisotropic media) and Hashin-Shtrikman bounds (for isotropic media) over wide ranges of porosities and saturations, and the predicted results agrees very well with the experimental data for MX80 bentonite, compared with Johansen's method. An experimental benchmark test problem under laboratory conditions for coupled thermo-hydro-mechanical processes of compacted FEBEX bentonite is simulated for validation of the model, and the results show that the model provides improved predictions of the evolution and distribution of temperature, with simpler forms of mathematical functions. (C) 2009 Elsevier Ltd. All rights reserved.
31.	Zimmerman, Robert W., et al. (författare) Thermal and electrical conductivity of composites with graded interfaces 2006 Ingår i: International Journal of Advances in Science and Technology. - 2229-5216. ; 45, s. 1097-1102 Tidskriftsartikel (refereegranskat)
32.	Öhman, Johan, 1973- (författare) Upscaling of Flow, Transport, and Stress-effects in Fractured Rock 2005 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract One of many applications of geohydraulic modelling is assessing the suitability of a site to host a nuclear waste repository. This modelling task is complicated by scale-dependent heterogeneity and coupled thermo-hydro-mechanical (THM) processes. The objective here was to develop methods for (i) upscaling flow and transport in fractured media from detailed-scale data and (ii) accounting for THM-induced effects on regional-scale transport. An example field data set was used for demonstration.A systematic framework was developed where equivalent properties of flow, transport, and stress-effects were estimated with discrete fracture network (DFN) modelling, at some block scale, and then transferred to a regional-scale stochastic continuum (SC) model. The selected block scale allowed a continuum approximation of flow, but not of transport. Instead, block-scale transport was quantified by transit time distributions and modelled with a particle random walk method at the regional scale.An enhanced SC-upscaling approach was developed to reproduce the DFN flow results more simply. This required: (i) weighting of the input well-test data by their conductivity-dependent test volumes and (ii) conductivity-dependent correlation structure. Interestingly, the best-fitting correlation structure resembled the density function of DFN transmissivities. Channelized transport, over distances exceeding the block scale, was modelled with a transport persistence length. A linear relationship was found between this persistence length and the macroscale dispersion coefficient, with a slope equal to a representative mean block-scale dispersion coefficient.A method was also developed to combine well-test data and rock-mechanical data in estimating fracture transmissivities, and its application was demonstrated.Finally, an overall sequential THM analysis was introduced allowing the estimation of the significance of waste-related thermo-mechanical (TM) effects on regional transport; here TM effects are calculated separately and their impact on fracture transmissivities were incorporated into the hybrid framework. For the particular case, their effects on regional-scale transport were small.

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