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991.
Eileen M. Murphy 《International Journal of Historical Archaeology》2011,15(3):409-428
Cilliní—or children’s burial grounds—were the designated resting places for unbaptized infants and other members of Irish society
who were considered unsuitable by the Roman Catholic Church for burial in consecrated ground. The sites appear to have proliferated
from the seventeenth century onwards in the wake of the Counter-Reformation. While a number of previous studies have attempted
to relate their apparently marginal characteristics to the liminality of Limbo, evidence drawn from the archaeological record
and oral history accounts suggests that it was only the Roman Catholic Church that considered cilliní, and those interred within, to be marginal. In contrast, the evidence suggests that the families of the dead regarded the
cemeteries as important places of burial and treated them in a similar manner to consecrated burial grounds. 相似文献
992.
993.
A variety of data indicate that the Carbonate aquifer in southern Manitoba is a heterogeneous and anisotropic aquifer wherein groundwater flow follows preferred flow path networks. Specific capacity tests show that aquifer transmissivity can vary by up to four orders of magnitude within 1 km. Geostatistical analysis reveals a strong anisotropy in the transmissivity field, with better spatial continuity in NE–SW and NW–SE directions, coincident with the dominant orientations of fractures observed in bedrock exposures. However, discrepancies between the orientation of highest fracture density and best transmissivity continuity suggest that either additional geological factors control the preferred flow network or there is a biased representation of the fracture pattern because all direct fracture observations came from the northern part of the study area. In an effort to investigate whether the geographically biased fracture data set represents the fracture pattern for the whole region, Landsat images and digital elevation maps were processed to extract linear features that may indicate subsurface fracture zones in areas where bedrock is covered by glacial sediments. The results suggest a consistent fracture pattern throughout the study area, indicating that the two observed fracture groups might have gone through different processes in terms of permeability development. Alteration by mineral cementation and dissolution along fracture surfaces may have preferentially improved the fracture permeability in one orientation, while reducing it in the other. The in situ stress field is also believed to play a major role in the preferred regional flow network. This paper discusses the evidence for the preferred flow path network and possible geological factors controlling aquifer anisotropy in this region. 相似文献
994.
The Red Lake mine trend, a deformation zone in the Archean Red Lake greenstone belt that hosts the world‐class Campbell‐Red Lake gold deposit, is characterized by abundant foliation‐parallel iron‐carbonate ± quartz veins with banded colloform‐crustiform structures and cockade breccias overprinted by silicification and gold mineralization. There is an apparent incompatibility between the cavity‐fill structures of the veins and breccias (typically developed at shallow crustal depths) and the upper greenschist to lower amphibole facies metamorphic conditions recorded in the host rocks (indicating relatively deep environments). This, together with the development of veins along the foliation plane, represents an enigmatic problem that may be related to the interplay between fluid dynamics and stress field. We approach this problem through systematic study of fluid inclusion planes (FIPs) in the vein minerals, including the orientations of the FIPs and the pressure–temperature conditions inferred from fluid inclusion microthermometry. We find that fluid inclusions in the main stage vein minerals (pregold mineralization ankerite and quartz and syn‐ore quartz) are predominantly carbonic without a visible aqueous phase, whereas many inclusions in the postore stage contain an aqueous phase. Most FIPs are subvertical, and many are subparallel to the foliation. High fluid pressure coupled with the high wetting angles of the water‐poor, carbonic fluids may have been responsible for the abundance of brittle deformation features. The development of subvertical FIPs is interpreted to indicate episodic switching of the maximum principal compressive stress (σ1) from subhorizontal (perpendicular to the foliation) to subvertical (parallel to the foliation) orientation. The subvertical σ1 is favorable for the formation of foliation‐parallel veins, as fractures are preferentially opened along the foliation in such a stress regime, the origin of which may be linked to the fluid source. 相似文献
995.
Layered low permeability rock units, like shales, represent seals or ‘cap‐rocks’ in a variety of geological settings. A continuous increase in the fluid pressure gradients across a virtually impermeable rock layer will ultimately lead to hydro‐fracturing. Depending on the boundary conditions, such fracturing may lead to the formation of a set of sub‐parallel cracks oriented more or less perpendicular to the cap‐rock layer. In this article, we propose a new numerical model that describes interactions between multiple cross‐cutting fractures in an elastic low permeability rock layer. The width of each fracture and the spacing between them are modeled as a force balance between the fluid pressure and the elastic forces in the cap‐rock and between each fracture. The model indicates that the system of fractures evolves toward a spatially periodic steady‐state distribution with a fixed fracture spacing and aperture. The results are similar for incompressible and compressible fluids. The steady‐state conditions depend on only two dimensionless parameters, and the fracture spacing is only weakly dependent on the cap‐rock thickness. This is in contrast to fracturing produced by simple extension of an elastic rock layer beyond the fracture strength, in which case fracture spacing is proportional to layer thickness. 相似文献
996.
The graphical and linguistic interpretation of the first six Etruscan numerals has long been confronted with the ambiguous assignment of the words huth and sa to either 4 or 6. Here, we show how the systematic combinatorial analysis of the numerals appearing on ancient southern Etrurian dice dated from the eighth to the third centuries bc , together with the careful comparison of the results with the only two existing dice carrying the alphabetical translations of the numerals conserved at the Bibliothèque Nationale de France, Paris, finally allows unambiguous mathematical resolution of the linguistic riddle, allowing the firm attribution of the numeral 6 to the graphical value huth and 4 to sa. Combinatorial analysis of the numerals distribution on the six faces of the die shows that only two of the 15 possible numerical combinations were actually in use in southern Etruria, and that during the fifth century bc there was a marked shift from the typical (1–2, 3–4, 5–6) combination used in the early seventh‐ to fifth‐century bc dice to the (1–6, 2–5, 3–4) combination used at later times and still largely adopted today. The largest body of archaeometric data on dice specimens from Etruria is presented, based on macroscopic examination, X‐ray diffraction, DRIFT spectroscopy and density measurements. 相似文献
997.
998.
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
999.
Panourias IG Stranjalis G Stavrinou LC Sakas DE 《Journal of the history of the neurosciences》2011,20(3):177-187
Numerous Hellenic terms have been gradually adopted during the development of modern medical science. Moreover, there are a significant number of words that derive directly from the Hippocratic texts. Hippocrates (ca. 460-ca. 377 BC), revered as the father of medicine, and his followers left behind a valuable heritage of medical knowledge that, practically, laid the foundations of Western medicine. Their theories, collected in Corpus Hippocraticum, transformed medicine by adding, mainly, clinical observation and inductive reasoning as significant parts of medical diagnosis and treatment. Additionally, Hippocratic writings have provided an invaluable heritage of medical terms for all medical fields. The present article examines the Hellenic and Hippocratic terminology referring to the spine and how this vocabulary has influenced and dominated upon modern spinal onomatology. 相似文献
1000.