Iron precipitation in a natural CO2 reservoir: Jurassic Navajo Sandstone in the northern San Rafael Swell,UT, USA

Diagenetic iron (oxyhydr)oxide minerals are common precipitates expected in CO₂ reservoirs, and these minerals record fluid flow for application to carbon capture and sequestration (CSS). Multiple mineralogy and spectroscopy analyses on a pore to meter scale characterize a well‐exposed, lithologically controlled, iron (oxyhydr)oxides reaction front in the Jurassic Navajo Sandstone. Dolomite is the most prevalent cement (up to 23 area%), followed by only several percent or less of iron (oxyhydr)oxides, kaolinite, illite, and gypsum cements. Bulk geochemistry based on diagenetic mineralogies in the reaction front is compared with the water chemistry from nearby modern spring effluent emanating from the Navajo Sandstone to conclude that similar fluids (i.e., CO₂‐charged, saline waters containing hydrocarbons) are responsible for the precipitation. A second comparison of bulk geochemistry and diagenetic mineralogies of the reaction front with data from other abundant Navajo Sandstone concretions in the Spencer Flat region (in south central Utah) shows that reservoir fluids likely vary spatially and temporally in the porous and permeable Navajo Sandstone. CO₂ injection into porous and permeable, quartz arenite, saline aquifers will likely result in minor clay and abundant dolomite precipitation that will significantly decrease porosity.     

Early pan‐Arabism in Egypt's July revolution: the Free Officers' political formation and policy‐making, 1946–54

Between 1952 and 1970, Gamal Abdel Nasser and Egypt's Free Officers Movement established the paradigmatic pan‐Arabist revolution from above. Yet it has become something of a cliché to maintain that the Free Officers had no blueprint of action before seizing power and that they later instrumentalised pan‐Arabism in their foreign policy, thinly veiling their actual commitments to Egyptian nationalism and imperialism. By contrast, this contribution underlines the impact of the British colonial context on the Free Officers' political formation and their early identification with pan‐Arabism in turn. Drawing on pamphlets, speeches, media output and memoirs, it shows that the Free Officers developed a distinctive form of anticolonial nationalism that emphasised social justice and invoked overlapping Egyptian and Arab identities. Their aspirations for liberation thus entailed a connected foreign policy and nation building programme in which pan‐Arabism was a prime – and early – component.     

Assessing the Impact of Typhoons on Historic Iron Shipwrecks in Chuuk Lagoon Through Changes in the Corrosion Microenvironment

The corrosion microenvironment of a dozen Second World War iron shipwrecks in Chuuk Lagoon, Federated States of Micronesia, was investigated to see if there were any measurable changes caused by a recent major typhoon. Seven previously inspected wreck sites were used for calibration to assess the environmental impacts. Five new wrecks, including the Fumitzuki, a destroyer of the Imperial Japanese Navy, were assessed at up to twice the depth of previous studies. The new data showed that the logarithm of the corrosion rate falls linearly with depth to 36 m. Measurements of corrosion potentials, concretion thickness and pH showed that many of the vessels suffered partial deconcretion during the typhoon Maysak in April 2015 with concomitant increases in the rate of decay. Regrowth of the colonising marine organisms are presently ameliorating the impact of the typhoon.     

从青铜器铭文看周代的赐"膰"礼

一、关于赐膰礼的争论在周代,天子、诸侯祭后有赐胙的习俗。如《左传》载庄公二十三年,楚成王贡献于周惠王,天子赐胙。僖公九年,王使宰孔赐齐侯胙。     

丸都山城高句丽铁器的金相与工艺

为探讨高句丽铁器加工业发展状况以及魏晋南北朝时期钢铁技术水平,利用金相显微镜对吉林省集安市丸都山城遗址出土铁器样品进行金相学检测及工艺研究,并结合以往高句丽铁器检测结果进行讨论。检测结果表明,工匠制造铁器时采用了"生铁淋口"、铸造后脱碳退火、铸铁脱碳钢材料锻打成型、锋刃部淬火、熟铁、低碳钢等不同材质的锻接、折叠锻打等加工技术。铁镞03JWN2T105②:12是迄今为止应用"生铁淋口"工艺的最早实例,将这种工艺的使用年代,前推至魏晋南北朝时期,相对于明代文献的明确记载提前1000年左右,相对于已报道的宋代实例早600余年,其发明时间应该还在此之前,该项发现对构建魏晋南北朝时期钢铁技术发展序列,具有十分重要的意义。     

Galvanic removal of metallic wrought iron from marine encrustations

Historic shipwrecks frequently contain a large proportion of wrought-iron tools, fasteners, and other types of artefacts. Encrustations readily form around such objects in many marine environments. Depending on many factors, the iron objects inside these encrustations may be well preserved, completely disintegrated, or poorly preserved but still present. The latter type of encrustation is every conservator's nightmare because removing the encrustation yields merely a poorly preserved artefact still in need of extensive additional conservation. Neatly separating the artefact from its encrustation in order to obtain a natural mould for casting is generally impossible. Having encountered this problem many times, the authors began to experiment with the extraction of metallic iron from poorly preserved encrusted artefacts using galvanic dissolution. Data on rates of dissolution were gathered for three experimental configurations. The results of a test conducted on an encrusted artefact were promising, but inconclusive.     

‘Guard the Good Deposit’: Technology,Provenance and Dating of Bipyramidal Iron Semi‐Products of the Durrenentzen Deposit (Haut‐Rhin,France)

In the early days of iron metallurgy in Western Europe, the most widespread type of ‘trade iron’ (semi‐product) was bipyramidal in shape. Although they are frequently found, little is known about how they were manufactured and circulated, or even about their age. An interdisciplinary approach was applied to the Durrenentzen deposit (Haut‐Rhin, France), the third‐largest in Europe in terms of artefact quantities, in an attempt to reconstruct the technological, social and economic context that caused them to be abandoned. A morphometric study of the 51 iron bars revealed a high degree of homogeneity, despite variations in detail. Four objects were selected for archaeometric studies. Metallographic analyses show internal differences (quality of the material, nature of the alloys and manufacturing techniques). Chemical analyses also showed different provenances. Finally, radiocarbon analyses of the carbon in steel (iron/carbon alloy) linked this deposit to the early Iron Age. This study provided the first benchmark for more general research, significantly changing perceptions of the economics of iron at the beginning of the Iron Age.     

试论陶器生活遗存所见西汉铁器手工业作坊的性质——以邰城铸铁作坊为案例

汉代铁器手工业的组织形式,一直以来讨论较多,却未有定论。本文提出,手工业作坊出土的陶容器的组合,有助于讨论作坊工匠的居住与组织形式,提供解决上述问题的线索。本文以陕西邰城铸铁作坊为案例,首先利用类型学建立分期框架,探讨作坊可能的运营持续时间。经统计分析,本文发现邰城作坊中炊煮陶容器的比例甚少。这一现象在西汉时期其他县级手工业作坊中相对普遍,但与战国时期作坊工匠居住于作坊范围内的情况不同,进而提出这一现象可能与工匠的居住和工作模式密切相关。本文指出,作坊出土的陶容器组合情况表明工匠可能不在作坊区内长期生活;铸铁作坊中工匠的身份可能也为雇佣工人,家庭式手工业作坊生产者的可能性不高。     

Methodological problems in the analysis of fossil non-artifactual wood assemblages from archaeological sites

The analysis of fossil wood fragments is often undertaken in relation to the archaeological excavation of a site. However, such analysis does not yet appear to have the strong methodological foundation that the investigation of many other classes of palaeoenvironmental evidence (e.g. seeds and pollen) have. Consequently, it is difficult to evaluate the value of fossil wood analysis at an archaeological site. Using data regarding non-artifactual wood assemblages at one site in southern Scotland, the relative merits of possible analysis are described and discussed. The results from such analyses tend to fall into two broad groups: (I) those of relatively high reliability, and (2) those of relatively low reliability. The results in the former group are often based on moderately secure methodology and tend to provide relatively non-interpretative information (e.g. species lists). On the other hand, those in the latter group are more often based on insecure interpretive methodology and provide relatively more stimulating information, such as evidence for prehistoric woodland management. There are many reasons for this situation, and these are discussed. In conclusion, it is argued that to increase the reliability of results in the second group (in particular), a full understanding of the taphonomy of non-artifactual fossil wood assemblages is needed, and that once this is available attention can then be paid, as elsewhere in environmental archaeology, to the problems of providing statistically valid samples for analysis.     

Analysis of the Effect of Provisional Ties on the Construction and Current Deformation of Mallorca Cathedral

This article presents the analysis of the structure of Mallorca Cathedral taking into account the influence on the structural behavior of auxiliary iron ties used during the construction process. Recent studies (Roca et al. 2012, 2013) presented some hypotheses about the construction process of the cathedral. This article complements the previous results by considering the use of auxiliary ties as temporary stabilizing device during the construction. Evidence of the use of ties during the construction has been recognized after a comprehensive survey. The study of the role of such ties and the effect of their later removal are studied by a FE analysis carried out on a representative bay of the structure. The study includes a time-dependent FE analysis after the removal of the ties to assess the long-term structural behavior. The results of the numerical analysis are compared with the deformation trends identified by means of a recent monitoring campaign.