The meteoritic origin of Tutankhamun's iron dagger blade          下载免费PDF全文

Daniela Comelli  Massimo D'orazio  Luigi Folco  Mahmud El‐Halwagy  Tommaso Frizzi  Roberto Alberti  Valentina Capogrosso  Abdelrazek Elnaggar  Hala Hassan  Austin Nevin  Franco Porcelli  Mohamed G. Rashed  Gianluca Valentini 《Meteoritics & planetary science》2016,51(7):1301-1309

Scholars have long discussed the introduction and spread of iron metallurgy in different civilizations. The sporadic use of iron has been reported in the Eastern Mediterranean area from the late Neolithic period to the Bronze Age. Despite the rare existence of smelted iron, it is generally assumed that early iron objects were produced from meteoritic iron. Nevertheless, the methods of working the metal, its use, and diffusion are contentious issues compromised by lack of detailed analysis. Since its discovery in 1925, the meteoritic origin of the iron dagger blade from the sarcophagus of the ancient Egyptian King Tutankhamun (14th C. BCE) has been the subject of debate and previous analyses yielded controversial results. We show that the composition of the blade (Fe plus 10.8 wt% Ni and 0.58 wt% Co), accurately determined through portable x‐ray fluorescence spectrometry, strongly supports its meteoritic origin. In agreement with recent results of metallographic analysis of ancient iron artifacts from Gerzeh, our study confirms that ancient Egyptians attributed great value to meteoritic iron for the production of precious objects. Moreover, the high manufacturing quality of Tutankhamun's dagger blade, in comparison with other simple‐shaped meteoritic iron artifacts, suggests a significant mastery of ironworking in Tutankhamun's time.  相似文献   

Vorticity analysis of the Palmi shear zone mylonites: new insights for the Alpine tectonic evolution of the Calabria–Peloritani terrane (southern Italy)     

Vincenzo Festa  Giacomo Prosser  Alfredo Caggianelli  Antonietta Grande  Antonio Langone  Daniela Mele 《Geological Journal》2016,51(4):670-681

New microstructural data on the mylonites from the well‐exposed Palmi shear zone (southern Calabria) are presented with the aim to shed light on both the kinematics and the geometry of the southwestern branch of the Alpine belt during Eocene. In the study area, located between the Sardinia–Corsica block and the Calabria–Peloritani terrane, previous large‐scale geodynamic reconstructions suggest the presence of strike–slip or transform fault zones dissecting the southwestern branch of the Alpine belt. However, there are no field data supporting the occurrence of these structures. This paper uses vorticity analysis technique based on the aspect ratio and the long axis orientation of rigid porphyroclasts in mylonitic marbles and mylonitic granitoids, to estimate the contribution of pure and simple shear of deformation during the movement of the Palmi shear zone. Porphyroclasts aspect ratio and orientation were measured on thin sections using image analysis. Estimates of the vorticity number, W_m, indicate that the Palmi shear zone recorded general shear with a contribution of pure shear of c. 65%. Then, the Palmi shear zone can be interpreted as a segment of a left‐lateral transpressive bend along the southern termination of the Eocene Alpine front. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Devitrite (Na2Ca3Si6O16)—structural, spectroscopic and computational investigations on a crystalline impurity phase in industrial soda-lime glasses     

Volker Kahlenberg  Daniela Girtler  Erik Arroyabe  Reinhard Kaindl  Daniel M. Többens 《Mineralogy and Petrology》2010,100(1-2):1-9

Single crystals of devitrite (Na₂Ca₃Si₆O₁₆) were synthesized as pale-yellow transparent needle shaped crystals using a Na₂MoO₄-flux. Experiments aiming to prepare the K-equivalent of devitrite from the corresponding K₂MoO₄-flux were unsuccessful. The crystal structure of devitrite was determined from single-crystal X-ray diffraction data (Mo-K_α radiation, 2θ_max.?=?25.34°, R_int?=?2.66%) and refined in space group P $ \bar{1} $ (no. 2) to R(|F|)?=?3.08% using 2,513 observed reflections with I?>?2σ(I). Unit-cell parameters are: a?=?7.2291(8), b?=?10.1728(12), c?=?10.6727(12) Å, α?=?95.669(9), β?=?109.792(10), γ?=?99.156(9)°, V?=?719.19(14) ų, Z?=?2. The structure belongs to the group of multiple chain silicates consisting of dreier quadruple chains, i.e. the crystallochemical formula can be written as $ {\hbox{N}}{{\hbox{a}}_2}{\hbox{C}}{{\hbox{a}}_3}\left\{ {{\mathbf{uB}}{,4}_\infty^1} \right\}\left[ {^3{\hbox{S}}{{\hbox{i}}_6}} \right.\left. {{{\hbox{O}}_{16}}} \right\} $ . Linkage between the bands running along [100] is provided by double chains of edge sharing CaO₆-octahedra as well as additional more irregularly coordinated Na- and Ca-cations located in the tunnel-like cavities of the mixed tetrahedral-octahedral framework. Structural investigations were completed by Raman and infrared spectroscopical studies. The allocation of the bands to certain vibrational species was aided by density functional theory (DFT) calculations.  相似文献   

The catalog of the meteorite collection of the Italian Museum of Planetary Sciences in Prato (Italy)     

Marco Morelli  Annarita Franza  Daniela Faggi  Giovanni Pratesi 《Meteoritics & planetary science》2023,58(7):945-954

For the first time, this paper presents to the planetary scientists' community the catalog of the meteorite collection preserved at the Italian Museum of Planetary Sciences (Museo Italiano di Scienze Planetarie, henceforth MISP) in Prato (Italy). Founded in 2005, MISP is a type specimen official repository approved by the Nomenclature Committee of the Meteoritical Society. It represents one of the few museums worldwide entirely devoted to planetary sciences. The catalog of its meteorite collection encompasses 430 meteorites for a total of 1536 specimens, including 291 thin sections, 184 thick sections, and 278 specimens that MISP has classified. Furthermore, MISP is currently classifying 57 other meteorites. Some samples were found during meteorite recovery expeditions in hot deserts, promoted by MISP in collaboration with diverse Italian universities and national research institutions. MISP also keeps an impact rocks collection comprising 257 samples. In a country like Italy, where most of the collected meteorites are housed in museums whose catalogs are not available online, the publication of the MISP meteorite collection catalog, together with the catalog of the impact rocks collection, represents not only a significant scientific primary source but also a remarkable tool for disseminating meteoritics to nonresearch audiences in educational activities and citizen science projects.  相似文献   

Uncovering spatiotemporal micromobility patterns through the lens of space–time cubes and GIS tools     

Arias-Molinares  Daniela  García-Palomares  Juan Carlos  Romanillos  Gustavo  Gutiérrez  Javier 《Journal of Geographical Systems》2023,25(3):403-427

Journal of Geographical Systems - In the past ten years, cities have experienced a burst of micromobility services as they offer a flexible transport option that allows users to cover short trips...  相似文献   

Seafloor distribution and last glacial to postglacial activity of mud volcanoes on the Calabrian accretionary prism,Ionian Sea     

Silvia Ceramicola  Daniel Praeg  Andrea Cova  Daniela Accettella  Massimo Zecchin 《Geo-Marine Letters》2014,34(2-3):111-129

Mud volcanoes (MVs) are abundant along the eastern Mediterranean subduction zones, recording mud breccia extrusion over long timescales (10⁶ years), but to date relatively few have been recognised in the northern Ionian Sea on the Calabrian accretionary prism (CAP). In the present study, the seafloor distribution and recent activity of MVs is investigated across a 35,600 km² sector of the CAP using a regional acoustic dataset (multibeam bathymetric and backscatter imagery, integrated with subbottom profiles) locally ground-truthed by sediment cores. A total of 54 MVs are identified across water depths of 150–2,750 m using up to four geophysical criteria: distinctive morphology, high backscatter, unstratified subbottom facies and, in one case, a hydroacoustic flare. Fourteen MVs are identified from 3–4 criteria, of which five have been previously proven by cores containing mud breccia beneath up to 1.6 m of hemipelagic sediments (Madonna dello Ionio MVs 1–3, Pythagoras MV and the newly named Sartori MV), while nine others are identified for the first time (Athena, Catanzaro, Cerere, Diana, Giunone, Minerva, ‘right foot’, Venere 1 and 2). Forty other as yet unnamed MVs are inferred from 1–2 geophysical criteria (three from distinctive morphology alone). All but one possible MV lie on the inner plateau of the CAP, landwards of the Calabrian Escarpment in a zone up to 120 km wide that includes the inner pre-Messinian wedge and the fore-arc basins, where they are interpreted to record the ascent from depth of overpressured fluids that interacted with tectonic structures and with evaporitic or shale seals within the fore-arc basins. The rise of fluids may have been triggered by post-Messinian out-of-sequence tectonism that affected the entire pre-Messinian prism, but Plio-Quaternary sedimentation rates and depositional styles support the inference that significant mud volcanism has taken place only on the inner plateau. Sedimentation rates across the CAP applied to a 12 khz sonar detection depth of 225 cm imply that all MVs with backscatter signatures (50 of 54) have erupted mud breccias within the last 56 ka, and within the last 12.5 ka in the fore-arc basins. Ages of eruption estimated from the depth of cored mud breccias at five MVs, and a seismo-stratigraphic relationship at a sixth, indicate episodes at the last glacial maximum ca. 20 ka BP and during the postglacial period. Eruptive episodes within the Calabrian MV province constitute recurrent geohazards, separated by longer periods of quiescent (subdued) fluid seepage that are likely to support gas hydrate formation and chemosynthetic ecosystems.  相似文献   

Development and validation of a coupled model system in the Baltic region—BALTIMOS     

Daniela Jacob 《Theoretical and Applied Climatology》2014,118(4):609-610

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Time variable Earth’s gravity field from SLR satellites   总被引：4，自引：4，他引：0  

Krzysztof Sośnica  Adrian Jäggi  Ulrich Meyer  Daniela Thaller  Gerhard Beutler  Daniel Arnold  Rolf Dach 《Journal of Geodesy》2015,89(10):945-960

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A comment on the article “A collinearity diagnosis of the GNSS geocenter determination” by P. Rebischung,Z. Altamimi,and T. Springer     

Michael Meindl  Gerhard Beutler  Daniela Thaller  Rolf Dach  Stefan Schaer  Adrian Jäggi 《Journal of Geodesy》2015,89(2):189-194

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Influence of mid-latitude circulation on upper Indus basin precipitation: the explicit role of irrigation     

Fahad Saeed  Stefan Hagemann  Sajjad Saeed  Daniela Jacob 《Climate Dynamics》2013,40(1-2):21-38

Since much of the flow of the Indus River originates in the Himalayas, Karakoram and Hindu Kush Mountains, an understanding of weather characteristics leading to precipitation over the region is essential for water resources management. This study examines the influence of upper level mid-latitude circulation on the summer precipitation over upper Indus basin (UIB). Using reanalysis data, a geopotential height index (GH) is defined at 200 hPa over central Asia, which has a significant correlation with the precipitation over UIB. GH has also shown significant correlation with the heat low (over Iran and Afghanistan and adjoining Pakistan), easterly shear of zonal winds (associated with central Asian high) and evapotranspiration (over UIB). It is argued that the geopotential height index has the potential to serve as a precursor for the precipitation over UIB. In order to assess the influence of irrigation on precipitation over UIB, a simplified irrigation scheme has been developed and applied to the regional climate model REMO. It has been shown that both versions of REMO (with and without irrigation) show significant correlations of GH with easterly wind shear and heat low. However contrary to reanalysis and the REMO version with irrigation, the REMO version without irrigation does not show any correlation between GH index and evapotranspiration as well as between geopotential height and precipitation over UIB, which is further confirmed by the quantitative analysis of extreme precipitation events over UIB. It is concluded that although atmospheric moisture over coastal Arabian sea region, triggered by wind shear and advected northward due to heat low, also contribute to the UIB precipitation. However for the availability of necessary moisture for precipitation over UIB, the major role is played by the evapotranspiration of water from irrigation. From the results it may also be inferred that the representation of irrigated water in climate models is unavoidable for studying the impact of global warming over the region.  相似文献