Heritage Stone 6. Gneiss for the Pharaoh: Geology of the Third Millennium BCE Chephren's Quarries in Southern Egypt

A remarkable campaign of decorative stone quarrying took place in the southwestern Egyptian desert almost 5000 years ago. The target for quarrying was Precambrian plagioclase−hornblende gneiss, from which several life-sized statues of King Chephren (or Khafra) and thousands of funerary vessels were produced. The former inspired George Murray in 1939 to name the ancient quarry site 'Chephren's Quarries.' Almost 700 individual extraction pits are found in the area, in which free-standing boulders formed by spheroidal weathering were worked by stone tools made from local rocks and fashioned into rough-outs for the production of vessels and statues. These were transported over large distances across Egypt to Nile Valley workshops for finishing. Although some of these workshop locations remain unknown, there is evidence to suggest that, during the Predynastic to Early Dynastic period, the permanent settlement at Hierakonpolis (Upper Egypt) could have been one destination, and during the Old Kingdom, another may have been located at pyramid construction sites such as the Giza Plateau (Lower Egypt). Chephren's Quarries remains one of the earliest examples of how the combined aesthetic appearance and supreme technical quality of a rock made humans go to extreme efforts to obtain and transport this raw material on an ‘industrial’ scale from a remote source. The quarries were abandoned about 4500 years ago, leaving a rare and well-preserved insight into ancient stone quarrying technologies. RÉSUMÉUne remarquable campagne d’extraction de pierres décorative a été mené dans le sud-ouest du désert égyptien il y a près de 5000 ans. La roche cible était un gneiss à plagioclase–hornblende, de laquelle ont été tiré plusieurs statues grandeur nature du roi Khéphren (ou Khâef Rê) et des milliers de vases funéraires. C’est pourquoi George Murray, en 1939, a donné au site de l’ancienne carrière le nom de 'Chephren’s Quarries.' On peut trouver près de 700 fosses d’extraction sur le site, renfermant des blocs de roches formés par altération sphéroïdale qui ont été dégrossis avec des outils de pierre pour la production de vases et de statues. Puis ils ont été transportés à travers l’Égypte jusqu’aux ateliers de finition de la vallée du Nil. Bien que la localisation de certains de ces ateliers demeure inconnue, certains indices permettent de penser que, de la période prédynastique jusqu’à la période dynastique précoce, l’établissement permanent à Hiérakonpolis (Haute Égypte) aurait pu être l’une de ces destinations; durant l’Ancien empire une autre destination aurait pu être située aux sites de construction de pyramides comme le Plateau de Giza (Basse Égypte). Les Chephren’s Quarries l’une des plus anciennes exemples montrant comment la combinaison des qualités esthétiques et techniques remarquables de la roche ont incité les humains à consentir de si grands efforts pour extraire et transporter ce matériau brute à une échelle industrielle d’un site éloigné. Les carrières ont été abandonnées il y a environ 4500 ans, nous laissant une fenêtre rare et bien conservé sur des technologies anciennes d’extraction de pierre de taille.Traduit par le Traducteu

GeoERA raw materials to support Europe’s resilience on raw materials

Europe’s vision to be a climate neutral economy by 2050 has ushered in the energy transition. Carbon-neutral energy supply is based on raw materials from which energy-critical elements for rechargeable batteries like cobalt, graphite, lithium and rare earth elements can be purified. In addition to direct energy generation, other future-oriented, environmentally friendly key technologies needed for digitisation and mobility can only be engineered by using raw materials (European Commission 2019).info:eu-repo/semantics/publishedVersio

Systemic inflammation early after kidney transplantation is associated with long-term graft loss: a cohort study

Background: Early graft loss following kidney transplantation is mainly a result of acute rejection or surgical complications, while long-term kidney allograft loss is more complex. We examined the association between systemic inflammation early after kidney transplantation and long-term graft loss, as well as correlations between systemic inflammation scores and inflammatory findings in biopsies 6 weeks and 1 year after kidney transplantation. Methods: We measured 21 inflammatory biomarkers 10 weeks after transplantation in 699 patients who were transplanted between 2009 and 2012 at Oslo University Hospital, Rikshospitalet, Norway. Low-grade inflammation was assessed with predefined inflammation scores based on specific biomarkers: one overall inflammation score and five pathway-specific scores. Surveillance or indication biopsies were performed in all patients 6 weeks after transplantation. The scores were tested in Cox regression models. Results: Median follow-up time was 9.1 years (interquartile range 7.6-10.7 years). During the study period, there were 84 (12.2%) death-censored graft losses. The overall inflammation score was associated with long-term kidney graft loss both when assessed as a continuous variable (hazard ratio 1.03, 95% CI 1.01-1.06, P = 0.005) and as a categorical variable (4th quartile: hazard ratio 3.19, 95% CI 1.43-7.10, P = 0.005). In the pathway-specific analyses, fibrogenesis activity and vascular inflammation stood out. The vascular inflammation score was associated with inflammation in biopsies 6 weeks and 1 year after transplantation, while the fibrinogenesis score was associated with interstitial fibrosis and tubular atrophy. Conclusion: In conclusion, a systemic inflammatory environment early after kidney transplantation was associated with biopsy-confirmed kidney graft pathology and long-term kidney graft loss. The systemic vascular inflammation score correlated with inflammatory findings in biopsies 6 weeks and 1 year after transplantation

Mass-Balance-Consistent Geological Stock Accounting: a New Approach toward Sustainable Management of Mineral Resources

Global resource extraction raises concerns about environmental pressures and the security of mineral supply. Strategies to address these concerns depend on robust information on natural resource endowments, and on suitable methods to monitor and model their changes over time. However, current mineral resources and reserves reporting and accounting workflows are poorly suited for addressing mineral depletion or answering questions about the long-term sustainable supply. Our integrative review finds that the lack of a robust theoretical concept and framework for mass-balance (MB)-consistent geological stock accounting hinders systematic industry-government data integration, resource governance, and strategy development. We evaluate the existing literature on geological stock accounting, identify shortcomings of current monitoring of mine production, and outline a conceptual framework for MB-consistent system integration based on material flow analysis (MFA). Our synthesis shows that recent developments in Earth observation, geoinformation management, and sustainability reporting act as catalysts that make MB-consistent geological stock accounting increasingly feasible. We propose first steps for its implementation and anticipate that our perspective as “resource realists” will facilitate the integration of geological and anthropogenic material systems, help secure future mineral supply, and support the global sustainability transition

GeoERA Raw Materials Monograph : the past and the future

ABSTRACT: GeoERA Minerals projects have produced data aimed at supporting Europe’s minerals sector and to assist the European Commission to realise its goals for raw materials. Data has been compiled on mineral occurrences and mineral provinces across Europe, in particular, areas with potential to host Critical Raw Materials. Anecdotal evidence from the minerals sector provides an indication of the likelihood of exploration leading to mine development. For every 1,000 mineral showings examined, only 100 may receive further exploration work and of those 100, only 10 may warrant more detailed sampling either through trenching, drilling or other means and of those 10 only 1 may proceed to an evaluation through a full feasibility study which itself has only 50% chance of being positive. Following this, any project for which a mine proposal is made must undergo a full evaluation and permitting by authorities including full public consultation. The proposal may or may not pass this scrutiny. In terms of a schedule, the generally accepted minimum time frame from discovery to production is 10 years and usually much more, up to 20 years.info:eu-repo/semantics/publishedVersio

Reconstructing a Medieval Underground Soapstone Quarry: Bakkaunet in Trondheim in an International Perspective

Underground medieval quarries are rare, in Norway and elsewhere in Europe. Thus the question: Could a big underground soapstone quarry have been opened at Bakkaunet in Trondheim (central Norway) in the Middle Ages? This question of stone procurement for Nidaros Cathedral – which is Europe’s northernmost medieval cathedral and a building heavily influenced by English traditions and fashions – has bothered us for the last 20 years. In this paper we discuss what we think the quarrymen did. It is a biography of the now almost lost Bakkaunet quarry, with a focus on the question about underground operations. But the paper also discusses stone procurement for Nidaros Cathedral in view of contemporary international, especially English, trends. The story is sad, for the open-cast part of this once great quarry, very close to the centre of Trondheim, has been successively destroyed by modern house building over the last century

The Building Stones from the Vanished Medieval Church at Onarheim, Tysnes, Hordaland County in Western Norway: Provenancing Chlorite Schist and Soapstone

This study centres on the provenance of soapstone and chlorite schist building stones at Onarheim church, 50 km south of Bergen and also provides geochemical results that are of key interest in further studies of Norwegian chlorite schist bakestone. The present Onarheim church is made from wood but building stones from previous stone churches at the site (12th century and early 19th century) are found in Foundation walls and the walls surrounding the churchyard. Geochemical analyses (main and trace elements, Sr-Nd isotope composition and rare earth profiles) from such stones were compared with results from similar analyses from a variety of quarries, including reference quarries in Rogaland and Trøndelag (chlorite schist). Unsurprisingly, the nearest soapstone quarry (Baldersheim) and the regional source of chlorite schist (Ølve-Hatlestrand) gave the best matches. However, the results also indicate two additional sources of soapstone, one of them is the distant Arnafjord quarry. This may represent an input of soapstone for postmedieval restoration and/or early 19th century construction works. A very important result of the study was that Sr-Nd isotope ratios distinguish between the known medieval chlorite schist quarries in Norway and different quarries at Ølve-Hatlestrand. Bakestone made from chlorite schist is found all over Norway and the opportunity to fingerprint their origin may aid in future interpretation of medieval trade patterns

Assessing individuals in team projects: A case study from computer science

a project-based course and after taking the course the students should be better able to analyse and specify software through models. There were two drivers for the course reform. Before the reform in 2009, the software models were used in an informal way and therefore it was hard to validate the correctness of the system from them. The students were instead assessed through a final written exam even if most of the work was done in the team project. But from contacts with industry, we got hold of a tool that enables testing and verification of model behaviour. So it was now possible to assess the teams by testing their models. The second driver for the reform was John Biggs ’ idea of constructive alignment (Biggs, 1996). The idea is that there should be a consistency between the learning objectives, the teaching methods and the assessment methods. If the assessment methods, in particular, do not match the learning objectives students tend to take a surface approach to learning. Since this was a project course we wanted our assessments to be more focused on the project, so we dropped the written exam. The question then became: How can we assign fair grades to individual members of the teams? We introduced a variety of new assessment methods in order to better judge the contribution of each student and what they had learned during the course. These methods comprised: voluntary written exams, peer assessment (grading and ranking of team members, and mid-course review of a report by another team), self assessment and a