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1.
New field and laboratory work has been carried out on two vitrified forts, Rhubh Aird Ghamhsgail near Arisaig and The Torr near Acharacle. Fieldwork confirms that both are constructed from rubble largely comprising local psammitic Moine Supergroup rocks and that their walls are relatively well preserved with large portions of vitrified material remain, particularly at The Torr, where remnants of up to four courses of stone facing occur. The preserved wall fills comprise mostly psammitic rubble set in a dark brown, vesicular, glassy to aphanitic matrix that in many places preserves evidence of downward flow. Conventionally, vitrification is explained through combustion of timber interlacing within the walls leading to melting that has been modelled in the granite system. However, considering Iron Age smelting technology, this leads to problems in obtaining high temperatures (≥1000 °C) over tens of metres of wall length. Geochemical analysis of the vitrification indicates that modelling the melting within the granite system is incapable of providing a partial melt matching the composition of vitrification. At The Torr, pelite fragments have been found near the base of the wall where partial melt occurs as black bubbles. In these fragments it appears that micas (largely biotite) have formed the melt via the reaction biotite + quartz = sanidine + orthopyroxene + liquid which takes place at temperatures c. 850 °C. Quench crystals in the melt include orthopyroxene, plagioclase, spinels, ilmenite, magnetite, anatase and apatite confirming that it was not a granite melt. These melted fragments are found next to material with biotite that, superficially, appears unmelted, suggesting that some of the heating took place perhaps away from the edifice and unmelted residue was utilised as part of the rubble fill, suggesting that in situ partial melting of the rubble is unlikely. However, in other parts of the edifice heat affected, yet unmelted, fragments are dominant. The new evidence indicates that vitrification occurred at lower temperatures than previously modelled and thus the melts could have been achieved more easily than previously thought.  相似文献   

2.
This paper reports the δ13C and δ15N values of bone collagen, muscle and skin from several late prehistoric–early colonial (AD 1490–1640) mummies from Perú's Ayacucho Valley. The mean of the δ13C and δ15N values of bone collagen are −11.5 ± 1.4 and 11.1 ± 0.7‰, respectively. The mean of the δ13C values for Vinchos skin is −11.8 ± 1.2‰ and the mean of δ15N values is 13.2 ± 0.5‰. The samples of muscle tissue have a δ13C mean of −11.9 ± 0.9‰ and a δ15N mean of 12.7 ± 0.3‰. The data from bone collagen indicate maize was the basis of the region's subsistence economy. A significant correlation between δ13C and δ15N values of bone collagen (R2 = 0.75) is consistent with the preferential fertilization of maize with composted manure. Both skin and muscle samples are consistently enriched in δ15N relative to paired samples of bone (2.1 ± 0.5 and 1.6 ± 0.7‰, respectively), possibly as a result of short term physiological stress or differential decomposition.  相似文献   

3.
The Laibin hominid represents one of the rare finds of modern Homo sapiens in China, rare for its relative completeness and well-established stratigaphic provenance. This paper presents the results of mass spectrometric U-series dating of intercalated calcite samples from the Laibin site. The capping flowstone and the calcite vein, which sandwich the hominid fossil-containing deposits, date to 38.5 ± 1.0 and 44.0 ± 0.8 ka, setting respectively the minimum and maximum ages to the fossils. The second flowstone layer is 112.0 ± 1.4 ka old, indicating that the cultural sequence may possibly extend to somewhere between 44 and 112 ka. Securely dated Laibin finds should be of importance in reconstructing human physical and cultural evolution in the region.  相似文献   

4.
The quantitative assessment of COH fluids is crucial in modeling geological processes. The composition of fluids, and in particular their H2O/CO2 ratio, can influence the melting temperatures, the location of hydration or carbonation reactions, and the solute transport capability in several rock systems. In the scientific literature, COH fluids speciation has been generally assumed on the basis of thermodynamic calculations using equations of state of simple H2O–nonpolar gas systems (e.g., H2O–CO2–CH4). Only few authors dealt with the experimental determination of high‐pressure COH fluid species at different conditions, using diverse experimental and analytical approaches (e.g., piston cylinder + capsule piercing + gas chromatography/mass spectrometry; cold seal + silica glass capsules + Raman). In this contribution, we present a new methodology for the synthesis and the analysis of COH fluids in experimental capsules, which allows the quantitative determination of volatiles in the fluid by means of a capsule‐piercing device connected to a quadrupole mass spectrometer. COH fluids are synthesized starting from oxalic acid dihydrate at = amb and = 250°C in single capsules heated in a furnace, and at = 1 GPa and = 800°C using a piston‐cylinder apparatus and the double‐capsule technique to control the redox conditions employing the rhenium–rhenium oxide oxygen buffer. A quantitative analysis of H2O, CO2, CH4, CO, H2, O2, and N2 along with associated statistical errors is obtained by linear regression of the m/z data of the sample and of standard gas mixtures of known composition. The estimated uncertainties are typically <1% for H2O and CO2, and <5% for CO. Our results suggest that the COH fluid speciation is preserved during and after quench, as the experimental data closely mimic the thermodynamic model both in terms of bulk composition and fluid speciation.  相似文献   

5.
Lichenometry is a method of dating that has been widely used in glaciated areas for determining the minimum age of exposure of a geomorphic landform during the late Holocene. This paper presents a regional calibration data set of lichen thallus sizes versus rock surface ages for the Huashan area, East China, based on measurements of yellow-green Rhizocarpon lichens on the known-age substrates at eight sites. An empirical relationship between thallus sizes and rock surface ages was established using both the traditional regression and the Bayesian approaches. Using the Bayesian calibration, the minimum age of the Huashan Grottoes was dated from 450 ± 60 to 330 ± 60 years ago, corresponding to the late Ming Dynasty (AD 1477–1632). These dates are generally consistent with those predicted from the regression-based linear growth curve. Our results suggest that applications of this technique can be safely extended to the non-glaciated areas.  相似文献   

6.
A vast amount of ceramics (among other grave goods) were recovered from Castillo de Huarmey, a Wari culture (650–1050 ce ) archaeological site on the north coast of Peru. In order to assess ceramic production area(s) and possible trade, political or cultural interactions with other regions, and to complement earlier petrographic analysis, electron microprobe analysis (EMPA) was conducted following a rarely used methodology in archaeology. The chemical composition of individual minerals in ceramics and sediments samples from the Huarmey Valley was obtained, focusing mainly on amphiboles, feldspars and pyroxenes. The results of the analyses clearly indicate that the majority of the ceramic analysed was made of raw material of local origin.  相似文献   

7.
Finds of basalt orthostats and mud building components from the archaeological site of Tilmen Höyük (south-eastern Turkey, early 2nd Millenium BC) preserve a glassy crust formed by vitrification of the material. It is proposed that such features are related to destructive fire events, which destroyed the wooden building elements and burned natural stones. The geoarchaeological and experimental approach confirms this hypothesis. The geochemical composition of experimental melts is comparable to that of natural basalts. Spot analyses evidence the heterogeneity of the melts, especially for mudbricks and ceiling plasters. It is concluded that the investigated finds were subjected to strong burning under oxidising conditions reached during a violent fire. Temperatures similar to those derived by experimental melting (1180–1195 °C) were likely reached in the fire at Tilmen in order to produce the glass observed.  相似文献   

8.
Cathodoluminescence (CL) of minerals such as quartz and zircon has been extensively studied to be used as an indicator for geodosimetry and geochronometry. There are, however, very few investigations on CL of other rock-forming minerals such as feldspars, regardless of their great scientific interest. This study has sought to clarify the effect of He+ ion implantation and electron irradiation on luminescent emissions by acquiring CL spectra from various types of feldspars including anorthoclase, amazonite and adularia. CL intensities of UV and blue emissions, assigned to Pb2+ and Ti4+ impurity centers respectively, decrease with an increase in radiation dose of He+ ion implantation and electron irradiation time. This may be due to decrease in the luminescence efficiencies by a change of the activation energy or a conversion of the emission center to a non-luminescent center due to an alteration of the energy state. Also, CL spectroscopy of the alkali feldspar revealed an in-crease in the blue and yellow emission intensity assigned to Al-O?-Al/Ti defect and radiation-induced defect centers with the radiation dose and the electron irradiation time. Taken together these results indicate that CL signal should be used for estimation of the α and β radiation doses from natural radionuclides that alkali feldspars have experienced.  相似文献   

9.
This study compares the results of Jaccard and Kulczynski‐2 similarity measures on a sample of ceramic assemblages to reveal spatio‐temporal patterns in the relationship between Neolithic sites in western Anatolia and south‐eastern Europe (c.6600–5500 bc ). The results show that the relationship between spatial distance and ceramic assemblage similarity has increased through time, which supports previous interpretations of leapfrog migrations and subsequent regionalization in ceramic assemblages during the Neolithic. A diachronic network analysis demonstrates the continuation of Aegean networking after the spread of farming.  相似文献   

10.
Tell Halaf is the locality of the ancient Aramaic city of Guzāna (c. 1000–800 bc ) in Syria. The statues of Tell Halaf were made from monolithic basalt blocks, comprising massive as well as amygdaloidal types. However, the exact location of the original quarries was as yet unknown. Reconnaissance mapping and sampling concentrated on the four basaltic centres in the vicinity of Tell Halaf, covering both south‐eastern Turkey and north‐eastern Syria. In addition, basaltic artefacts from the two archaeological sites of Tell Beydar (c. 2700–2300 bc ) and Djebelet el Beda (c. 2600–2350 bc ) were investigated. All basalt samples were analysed for their bulk rock major and trace element compositions by X‐ray fluorescence, ICP–MS analysis and the mineral chemistry of individual minerals by combined electron microprobe analysis and laser‐ablation ICP–MS. The data show that basalt works of art from all three archaeological sites were derived from the Syrian basalt plateau of Ard esh‐Sheikh, approximately 57 km south of Tell Halaf. Accordingly, this basalt quarry was actively exploited over a considerable time span of c. 1900 years. This study demonstrates that petrographic and geochemical investigations of basalt, combined with electron microprobe and laser‐ablation ICP–MS analysis of minerals, are powerful tools to discriminate between possible sources of raw materials, especially if isotopic data yield unsatisfying results.  相似文献   

11.
Soluble salts are indigenous to the marine sediments of the Esna Formation and Thebes Formation in central Egypt. Natural weathering processes and human impact cause salt efflorescence in tombs and on walls of ancient Egyptian monuments in the Theban Necropolis, resulting in the disintegration of wall paintings and carved hieroglyphs. Determination and quantification of soluble salts and measurements of the porosity were done on tomb marls in order to understand the origin and damage potential of the salts in the royal tombs of the Valley of the Kings. The study shows that sodium chloride (NaCl) is the predominant salt species. Sulphates, anhydrite (CaSO4) and gypsum (CaSO4 . 2 H2O) also occur in the limestone deposits of the Thebes Formation and the underlying shale deposits of the Esna Formation. Member I of the Thebes Formation, into which most of the ancient tombs were hewn, shows the highest amount of soluble salts (up to 6·2 wt-% dry). In addition, the porosity and permeability of the marls in Member I are high, enhancing water molecules and brine migration. Wetting and drying of the tomb surfaces in the past has affected solution, transportation and recrystallization of water soluble minerals, and has led to major destruction of wall paintings and ornamentations. This study shows that large amounts of salt minerals still remain in the wall rocks. Future humidity changes due to flash floods and tourists may favour salt crystallization in the ancient Egyptian monuments. The authors urge the authorities to undertake steps to prevent further destruction to save the magnificent cultural heritage found in the Thebes area.  相似文献   

12.
Evaluating protein residues on Gainey phase Paleoindian stone tools   总被引:1,自引:1,他引:0  
Blood protein analysis provides a method for acquiring and interpreting archaeological data bearing on human–animal relationships. The present study makes use of cross-over immunoelectrophoresis (CIEP) and a large sample of stone tools (N = 130) from an early Paleoindian site pertaining to the Gainey phase (ca. 11,200 BP) of the Midwestern USA. Results are used to interpret toolkit organization and site structure, and indicate that hafted tools with longer use-life potentialities are more likely to be associated with preserved residues than are tools of a more ad hoc or situational character. Protein residues derived from cervids are the largest category of identified samples, a result consistent with an interpretation that these animals were important first-line resources of Gainey phase populations. The identification of caribou (Rangifer sp.) is notable. Interpretations of subsistence importance, however, must be tempered by an appreciation of the possible confounding effects of tool manufacture and maintenance in early Paleoindian contexts.  相似文献   

13.
With the aim to study alteration processes of the rock hewn churches from Lalibela (Ethiopia), we applied Laser Induced Breakdown Spectroscopy (LIBS) technique to measure the elemental composition both of the bulk rock materials and their external layers, exposed to the environmental factors. The analytical plasma was generated by nanosecond pulses of an Nd: YAG laser emitting at 1064 nm. Different major and minor sample constituents were detected, including Ca, Mg, Na, Fe, Ti, Al and K. The detected O emission originates both from air surrounding and the sample, while the intensity of N lines, coming exclusively from air, was used for the LIBS signal normalization. By depth profiling of the weathered basalt rock, we observed a lower presence of K in the external layers, corresponding to the first 5 laser shots. The emission from this element is anti-correlated with the line intensities from O, and this was attributed to the variations in relative abundances of clay minerals and K-feldspar. The analogue measurements were performed on the tuff rock, and compared to the spectra from powder samples containing only the external soft material, scratched from the rocks. These analyses show an abundance of H in the weathered, wetted layers and suggest that cations are lost from the constituent primary minerals and replaced by H+; this process disrupts the lattice structure and causes a marked loss of strength. The studies presented here demonstrate that LIBS is a useful technique for studying the alteration processes in the rocks, caused by environmental factors.  相似文献   

14.
The late Stone Age Pitted Ware site at Ajvide, Gotland, in the Baltic Sea, Sweden, has revealed a large deposit of fishbone and approximately 400 bone fishhooks, complete and incomplete. Cod (Gadus morhua), which is one of the most abundant fish species in the bone assemblage, was probably caught with hook and line fishing. To investigate the fishhooks' field of application, a morphological and morphometric study was performed on 384 available hooks. Two sets of replicas made of four selected original fishhooks were submitted to a strength test. A breakage study of the incomplete hooks in comparison with the strength-tested hooks was carried out in order to distinguish fresh breaks from dry breaks. It seems that a certain morphology for fishhooks was preferred at Ajvide, indicating they were produced by skilled craftsmen for special usage. The strength test showed that the hooks had a weight bearing capacity more than the average size of cod caught at Ajvide. Using results of these tests, we predicted that the mean breaking strength of 46 intact Ajvide hooks was 96.6 ± 26.1 (s.d.) Newtons (equivalent to 9.85 ± 2.7 kg). The design of fishhooks changed somewhat over time, being slightly larger in the oldest layers of the site. The breakage patterns of the hooks show that the bow was the most common area of breakage. The design and weight bearing capacity of the hooks point to a specialized cod fishery from boats in deep water.  相似文献   

15.
The strontium (Sr) concentration in bioapatite of human bone and teeth reflects the Sr concentration in food that is differentiated by two major factors: an abundance of Sr in local soils and the biopurification effect along the trophic levels. Eastern Syria is an area with a relatively high concentration of Sr within the Euphrates valley and a low concentration of Sr beyond the valley. For this reason, the strontium/calcium (Sr/Ca) ratio in human enamel retrieved from skeletons buried in cemeteries within the Euphrates valley may be used as a proxy for food provenience in a local population. A sample of human teeth (N = 72) from Tell Ashara and Tell Masaikh was divided into seven temporal subsets covering periods between c.2200 bce and the early 20th century ce . A significant difference in Sr/Ca values between temporal subsets is observed. The Sr/Ca values in later subsets are negatively correlated with δ13C values, indicating the wider exploitation of steppe areas outside the valley with more wild C4 grasses and a low Sr concentration. For periods with lower Sr/Ca values (c.2200–1900 bce and 19th–20th centuries ce ) there is additional textual and isotopic evidence for food transportation from outside the river valley, supporting the interpretation of Sr/Ca values as a proxy for food provenience in this specific area.  相似文献   

16.
Preliminary studies into methods for improving and safeguarding the preservation of waterlogged archaeological wooden artefacts are presented. Mannitol, sorbitol and trehalose have been tested as replacements for polyethylene glycol (PEG) as a treatment prior to freeze-drying of wooden archaeological objects. The highest anti-shrink efficiency achieved in this short experiment was (70 ± 15) % using a 20% weight per volume solution of sorbitol after soaking for one week. The collapse or eutectic temperature of each solution used was determined using a freeze-drying microscope. Importantly, it was noted that the collapse temperature of the solutions was reduced by several degrees after use for treatment of the wood samples for one month. A freeze-drying microscope with a cold light source has been used to observe the real-time freeze-drying behaviour of various treatments inside a thin section of wood, confirming that this novel technique is indeed possible and useful. Lastly, the effects of magnesium phytate as an iron chelator have been studied. It was found that the treatment lowers the collapse temperature of a PEG 600/2000 solution by roughly 3 °C meaning that objects must be freeze-dried at a correspondingly lower temperature. Iron K-edge X-ray absorption near-edge spectroscopy analysis showed that the treatment extracted approximately half of the iron(III) ions present in the timbers.  相似文献   

17.
Based on analyses of the ecological environments of the Neolithic sites along the Chan and Ba Rivers in the Xi’an area (Shaanxi Province, China), it was found that the characteristic factors of the sites had a very close relationship with the nearby river. The characteristic factors of Neolithic sites have been analysed and defined as mathematical parameters by statistical methods. A mathematical model of the human–land relationship between Neolithic sites and rivers has been established using the stepwise regression procedure REGRESS in SPSS®. The mathematical model is Y = 496.153 – 4.833X+ 113.692X3 + 725.097X5 – 27.683X3X4. It shows that the distance (Y) from a site to a river has a marked relationship with the site area (X1), the river flux (X3), the site location (X5) and river ratio drop (X4). The model shows that the relationship between the sites and the river is in accordance with the conclusions of archaeological research. The mathematical model not only offers theoretical guidance for the archaeological excavation of Neolithic sites in Xi’an, but also contributes to the archaeological environmental research of Xi’an Neolithic sites.   相似文献   

18.
The Upper Palaeolithic site of the Abri Pataud (Dordogne, France) has been the subject of numerous14C age determinations which cover the period from 20,400±450 years (OXA-373) to 34,250±675 years (Grn-4507). The racemization ratios of aspartic acid have been determined in 26 fossil bones. The bones are present in two different sedimentary surroundings: levels (fine deposits with numerous artefacts and fossil bones) and “éboulis” (coarse deposits derived from the neighbouring limestone cliff). Racemization ratios for total aspartic acid have a poor correlation with14C ages (respectivelyr2=0·59 and 0·82 for the two environments) but apparent racemization rates are clearly dependent on the type of deposits (levels: K=4·4×10−6year−1; éboulis: K=9×10−6year−1).Racemization ratios of aspartic acid in a high molecular weight protein fraction (>10,000 Da) correlate much better with14C ages (r2=0·999) for the samples from the levels (k=2·1×10−5year−1). From this regression line we estimate ages for two Aurignacian levels: level 6≈29,560 years and level 9≈30,440 years .It is noteworthy that none of the regression lines intercepts the origin. Racemization of aspartic acid appears to occur only after a delay of many thousands of years. This phenomenon could be the result of a coupling between the degradation of proteins and the racemization of amino acids.  相似文献   

19.
BOOK REVIEWS     
R. Horsley , ed.: A People's History of Christianity, Vol. 1, Christian Origins. Minneapolis: Fortress, 2005. Irfan Shahîd : Byzantium and the Arabs in the Sixth Century. Vol. 2, Part 1: Toponomy, Monuments, Historical Geography, and Frontier Studies. Washington, DC: Dumbarton Oaks Research Library and Collection, 2002; pp. xxxvi + 469, 15 maps, 8 plates. Daniel Hobbins : The Trial of Joan of Arc. Cambridge, MA: Harvard University Press, 2005. Ernan Mc Mullin , ed.: The Church and Galileo. Notre Dame, IN: University of Notre Dame Press, 2005. pp. xii + 408. Stewart J. Brown and George Newlands , eds.: Scottish Christianity in the Modern World. Edinburgh, T & T Clark, 2000. pp. 323. Adrian Burdon : Authority and Order: John Wesley and his Preachers. Aldershot: Ashgate, 2005. pp. vi + 117. Max Charlesworth , Françoise Dussart and Howard Morphy , eds.: Aboriginal Religions in Australia: An Anthology of Recent Writings. Aldershot: Ashgate Publishing, 2005. pp. xiv + 324. André Möller : Ramadan in Java: The Joy and Jihad of Ritual Fasting. Lun University: Lund, Sweden, 2005. pp. 451. John Clifford Holt : The Buddhist Viṣnu: Religious Transformation, Politics, and Culture. New York: Columbia University Press, 2004. pp. 441. Kristi L. Wiley : Historical Dictionary of Jainism. Lanham, ML: The Scarecrow Press, Inc., 2004. pp. 287. Iqbal Singh , S. Radhakrishan , and Arvind Sharma , with an introduction by Matthew T. Kapstein : The Buddhism Omnibus — Comprising Gautama Buddha, The Dhammapada and The Philosophy of Religion: A Buddhist Perspective. Oxford and New York: Oxford University Press, 2004. pp. xxii + 818. Aline H. Kalbian : Sexing the Church: Gender, Power, and Ethics in Contemporary Catholicism. Bloomington, IN: Indiana University Press, 2005. pp. x + 169. Dianne Kirby , ed.: Religion and the Cold War. London: Palgrave Macmillan, 2003. pp. 245. Nils Holger Petersen , Claus Clüver , and Nicholas Bell , eds.: Signs of Change: Transformations of Christian Traditions and Their Representations in the Arts, 1000–2000. Amsterdam and New York: Rodpi, 2004. pp. xvi + 490. Craig Wright : The Maze and the Warrior: Symbols in Architecture, Theology and Music. Cambridge, MA: Harvard University Press, 2001. Michael Kessler and Christian Sheppard (eds.): Mystics: Presence and Aporia. Chicago: University of Chicago Press, 2003. Frances S. Adeney : Christian Women in Indonesia: A Narrative Study of Gender and Religion. Syracuse, NY: Syracuse University Press, 2003; pp. xi + 226. John Moorhead : Ambrose: Church and Society in the Late Roman World, Harlow Essex, Pearson Education, 1999.  相似文献   

20.
Arsenic has previously been measured in a bone sample of a c. 5-year-old Mesolithic child from Nivaagaard in Denmark yielding an anomalously high value of 13 μg/g. In the present work we show that other individuals at a nearby site also exhibit elevated arsenic levels, whereas individuals from other Mesolithic sites in Denmark are found to have quite low As-concentrations. Several attempts to reveal the source of the arsenic are reported: A railway track near the site, where the railway sleepers were suspected to have been impregnated with As leading to transport or diffusion of As into the adjacent soil; Several food items, the remains of which were found at the site, and one food item not preserved in the excavation, i.e. seaweed. Finally, it is shown that the most likely explanation of the elevated arsenic levels in human bones at Nivaa is diagenesis.  相似文献   

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