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Replication Data for: "Laboratory Evaluation of Mechanical Properties of Draupne Shale Relevant for CO2 Seal Integrity"
No full textThe dataset provides experimental data used in the analysis leading up the publication "Laboratory Evaluation of Mechanical Properties of Draupne Shale Relevant for CO2 Seal Integrity". Data provided is from triaxial compression tests and one incremental loading oedometer test on the Draupne shale from the Ling depression.Results are presented from one oedometer and eleven triaxial compression tests on vertical and horizontal samples of the North Sea Draupne shale aimed at deriving me-chanical caprock properties relevant for seal integrity evaluation during CCS operations. Important findings from the laboratory study are:
• For the intact vertical samples an apparent cohesion of 7.5 MPa and a friction angle of 18.7° was estimated based on constructed Mohr Coulomb failure envelope. Rela-tively similar values were found for the horizontal samples (cohesion 8.4 MPa and friction 19.4°). In terms of residual strength, the constructed failure envelopes showed a significant reduction in cohesion, whereas the reduction in friction angles was less significant. Both intact and residual strengths are important in operational design of CO2 injection operations to avoid fracture creation or reactivation of pre-existing weakness planes.
• Secant undrained Young's modulus measured between 40 and 60 % of peak stress was between 4.2 and 4.7 GPa for vertical samples and 5.7 – 7.1 GPa for horizontal samples. Average secant Poisson's ratio for samples of both principal directions were close to 0.5.
• Whereas the measured constrained modulus from oedometer testing showed little or no stress dependency, the consolidation coefficient decreased with increasing effec-tive vertical stress. Hydraulic permeability estimated from constrained modulus and consolidation coefficient therefore also decreased with increasing effective vertical stress. Increasing effective vertical stress from 33 to 75 MPa caused a reduction in hy-draulic permeability of nearly 50 %.
• The apparent pre-consolidation stress determined from oedometer incremental loading was 36.5 MPa. Consequently, the tested Draupne shale is considered nor-mally consolidated to lightly overconsolidated. The measured undrained strength from triaxial normalized against the effective vertical consolidation stress correlated quite well with overconsolidation ratio following the SHANSEP normalization pro-cedure developed for clays
Replication Data for: Experimental evaluation of predicted undrained pore pressure generation as function of stress path and orientation in the Draupne shale
No full textExperimental data from triaxial testing of the Draupne shale. Data supports the interpretation given in the aforementioned publication
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Caprock interaction with CO2 : Geomechanical and geochemical effects
No full textSubsurface storage of carbon dioxide is often considered one of the most promising ways of reducing atmospheric levels of CO2. The safety of the operation is closely related to the performance of caprocks overlying the formations in which CO2 is injected. Interactions between CO2 or CO2/brine and caprocks can alter the sealing capacity which prevents upward migration of CO2. This thesis is a part of the SSC Ramore project, concerned with risk assessment related to underground geological storage of CO2. A new experimental design allowing a caprock core to be flooded with CO2 was prepared and tested at the Norwegian Geotechnical Institute (NGI). The initial aim of injecting CO2 saturated brine into a sample from the Draupne Formation had to be altered due to experimental difficulties encountered. Instead it was decided to perform a capillary breakthrough pressure test. By applying a gradually increasing pressure gradient across the sample, an apparent flow of supercritical CO2 was obtained at a breakthrough pressure of ~3.5 MPa. However, the interpretation of this as a real breakthrough pressure was made difficult by the simultaneous onset of a significant radial expansion. Geochemical effects of Draupne claystone interacting with acidic CO2-saturated brine were investigated in a batch reactor at the University of Oslo (UiO). Small amounts of powdered claystone material were reacted with solutions with pH ranging from 2 – 10. At the pH levels expected in underground geological formations after CO2 injection, the experiment indicates that most of the carbonates present in the Draupne caprock are dissolution-prone
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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