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1.
The act of scalping has long been associated with Native American conflict‐related human body part trophy taking. Reasons for their removal were varied and often included communal and personal factors. Previous research has identified several different types of scalp removals based on the amount of soft tissue affected during the process of scalping. One of these types can involve the removal of the ears. Through reanalysis of known scalping victims within the middle Tennessee Valley of North Alabama, we have identified five cases where victims were both scalped and had their ears removed. These cases provide a unique understanding of the practice of human body part trophy taking. They support ethnographic accounts that indicate ear removal has great time depth and was geographically widespread. Although the five cases presented here are similar to total compound scalpings, they actually represent total simple scalpings. Unlike total compound scalpings, where the ears are removed attached to the skin of the scalp, these cases show evidence of secondary removal of the ears after the scalp was already detached. This secondary removal of the ears after the act of scalping supports the interpretation that the aggressors intended different purposes for each trophy. It is likely that the scalp and ears each had their own meaning. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

2.
For years, the pre‐Hispanic Chachapoya of Northern Peru have been described as the ‘Warriors of the Clouds’. A more detailed look at newly excavated osteological samples from the highland site of Kuelap allows us to better examine the types of traumatic injuries among the Chachapoya. This paper describes an individual with evidence of a recent scalp removal including cut marks encircling the vault and a large area of active inflammatory response due to exposure of the outer table. The degree of osseous response and a small area of healing indicate short‐term survival. A second fragmentary skull demonstrates similar features but more advanced healing. The location and patterning of the cut marks are consistent with North American Indian pre‐historic and historic cases of scalping. The skulls of these two individuals provide the first osteological evidence of scalp removal from a pre‐Hispanic South American Andean context, although it is difficult to determine the motivation whether for therapeutic treatment or trophy taking. These cases, along with other evidence of interpersonal violence and cranial trauma, serve to elucidate the possible volatile nature of cultural contact between this region and lowland Amazonian tribes, where scalps and trophy heads were commonly taken in raids. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

3.
Bone changes resulting from avulsions involving vertebral endplates have had little, if any, systematic attention in palaeopathological literature. To gain insight into their occurrence and into their variety, two archaeological skeletal collections covering the period AD 1455–1824 were examined. Additional skeletal material was used to illustrate typical examples. A quarter of the 44 adults who had adequate numbers of vertebrae at all spinal levels showed minor to major vertebral endplate changes as a result of avulsion injuries. The male/female ratio was 7:4. The ratio of individuals with injuries contracted during their youth and during their adulthood was 3:8 (n=11). Approximately half of the affected individuals showed such changes in multiple vertebrae. In about one third of the cases, concomitant vertebral fractures, which did not involve the endplates, were recorded. Since the existing classifications of endplate changes from avulsion injuries were developed on the basis of clinical diagnoses made by means of X‐ray or by autopsy, an adapted and extended outline for palaeopathological use is proposed. A series of differential diagnoses is discussed. Although, in general, the poor preservation of archaeological spines hampers epidemiology, the diagnosis of spinal avulsion injuries offers interesting information at the individual level. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

4.
The capillary‐sealing efficiency of intermediate‐ to low‐permeable sedimentary rocks has been investigated by N2, CO2 and CH4 breakthrough experiments on initially fully water‐saturated rocks of different lithological compositions. Differential gas pressures up to 20 MPa were imposed across samples of 10–20 mm thickness, and the decline of the differential pressures was monitored over time. Absolute (single‐phase) permeability coefficients (kabs), determined by steady‐state fluid flow tests, ranged between 10?22 and 10?15 m2. Maximum effective permeabilities to the gas phase keff(max), measured after gas breakthrough at maximum gas saturation, extended from 10?26 to 10?18 m2. Because of re‐imbibition of water into the interconnected gas‐conducting pore system, the effective permeability to the gas phase decreases with decreasing differential (capillary) pressure. At the end of the breakthrough experiments, a residual pressure difference persists, indicating the shut‐off of the gas‐conducting pore system. These pressures, referred to as the ‘minimum capillary displacement pressures’ (Pd), ranged from 0.1 up to 6.7 MPa. Correlations were established between (i) absolute and effective permeability coefficients and (ii) effective or absolute permeability and capillary displacement pressure. Results indicate systematic differences in gas breakthrough behaviour of N2, CO2 and CH4, reflecting differences in wettability and interfacial tension. Additionally, a simple dynamic model for gas leakage through a capillary seal is presented, taking into account the variation of effective permeability as a function of buoyancy pressure exerted by a gas column underneath the seal.  相似文献   

5.
Like jazz improvisation, the meaning of Swift v. Tyson was elusive. 1 Justice Joseph Story's 1842 opinion concerning an important commercial‐law issue arose from a jury trial. 2 When the creditor plaintiff appealed, counsel for the winning debtor raised as a defense Section 34 of the 1789 Judiciary Act. The federal circuit court disagreed about the standing of commercial law under Section 34. Although profound conflicts otherwise divided nationalist and states'‐rights proponents, the Supreme Court endorsed Story's commercial‐law opinion unanimously. 3 New members of the Court and the increasing number of federal lower‐court judges steadily transformed the Swift doctrine; after the Civil War it agitated the federal judiciary, elite lawyers, and Congress. 4 Asserting contrary tenets of American constitutionalism, the Supreme Court overturned the ninety‐six‐year‐old precedent in Erie Railroad v. Tompkins (1938). 5 The Swift doctrine's resonance with changing times was forgotten. The Court and the legal profession established, transformed, and abandoned the doctrine though an adversarial process and judicial instrumentalism. Although the policy of each decision reflected its time, Story's opinion was more consistent with the federalism of the early Constitution than was Erie. 6  相似文献   

6.
The paper deals with the major chemistry and stable isotopes (hydrogen, oxygen, carbon, sulfur, strontium) of waters and solutes from the Salar de Atacama basin (Rio Pedro, Honar Creek and Laguna Chaxa) and Andean Altiplano (Laguna Miñique and Laguna Miscanti). The water inflows of the Salar are chemically quite different, the Rio San Pedro being of Na‐Cl type and the Honar Creek of Na‐HCO3 type, in keeping with the sedimentary‐evaporitic and volcanic nature of the catchment rocks respectively. The δ34S and δ18O values of sulfate and the 87Sr/86Sr ratio of strontium in the streams match those of drained rocks, whereas the δ13C values of dissolved carbonate are largely controlled by vegetation. The lagoons are evaporated meteoric water bodies, and the relative air humidity estimated from the slope of the isotopic evaporation line is in accordance with historical data on air humidity in the area. The Laguna Chaxa is Na‐Cl rich, and its isotopic composition are consistent with a mixed sedimentary‐volcanic provenance of sulfur and strontium solutes. The Laguna Miñique is Na‐SO4 rich, and its sulfate δ34S is nearly identical to that of Laguna Chaxa. The δ13C(HCO3) values are quite different in the Laguna Chaxa and Laguna Miñique, with the former being notably enriched in 13C probably because of preferential uptake of 12C by the high biological productivity occurring in the lagoon. The limited set of new data is interpreted in the context of a much larger literature database. In particular, previous chemical data on inflows and brines in the Salar de Atacama were revisited, and compared with evaporation path models and mineral stability diagrams (boron, lithium and Mg‐minerals) computed using updated software and thermodynamic databases. The modeling shows that the removal of boron and lithium from sulfate‐rich brines possibly occurs, respectively, as ulexite and sulfate salts, and carnallite should be the final magnesium phase of the brine evolution.  相似文献   

7.
Mineral deposits in the Cupp‐Coutunn/Promeszutochnaya cave system (Turkmenia, central Asia) record a phase of hydrothermal activity within a pre‐existing karstic groundwater conduit system. Hydrothermal fluids entered the caves through fault zones and deposited sulphate, sulphide and carbonate minerals under phreatic conditions. Locally, intense alteration of limestone wall rocks also occurred at this stage. Elsewhere in the region, similar faults contain economic quantities of galena and elemental sulphur mineralization. Comparisons between the Pb and S isotope compositions of minerals found in cave and ore deposits confirm the link between economic mineralization and hydrothermal activity at Cupp‐Coutunn. The predominance of sulphate mineralization in Cupp‐Coutunn implies that the fluids were more oxidized in the higher permeability zone associated with the karst aquifer. A slight increase in the δ34S of sulphate minerals and a corresponding δ34S decrease in sulphides suggest that partial isotopic equilibration occurred during oxidation. Carbonate minerals indicate that the hydrothermal fluid was enriched in 18O (δ18OSMOW ~ + 10‰) relative to meteoric groundwater and seawater. Estimated values for δ13CDIC (δ13CPDB ~ ? 13‰) are consistent with compositions expected for dissolved inorganic carbon (DIC) derived from the products of thermal decomposition of organic matter and dissolution of marine carbonate. Values derived for δ13CDIC and δ18Owater indicate that the hydrothermal fluid was of basinal brine origin, generated by extensive water–rock interaction. Following the hydrothermal phase, speleothemic minerals were precipitated under vadose conditions. Speleothemic sulphates show a bimodal sulphur isotope distribution. One group has compositions similar to the hydrothermal sulphates, whilst the second group is characterized by higher δ34S values. This latter group may either record the effects of microbial sulphate reduction, or reflect the introduction of sulphate‐rich groundwater generated by the dissolution of overlying evaporites. Oxygen isotope compositions show that calcite speleothems were precipitated from nonthermal groundwater of meteoric origin. Carbonate speleothems are relatively enriched in 13C compared to most cave deposits, but can be explained by normal speleothem‐forming processes under thin, arid‐zone soils dominated by C4 vegetation. However, the presence of sulphate speleothems, with isotopic compositions indicative of the oxidation of hydrothermal sulphide, implies that CO2 derived by reaction of limestone with sulphuric acid (‘condensation corrosion’) contributed to the formation of 13C‐enriched speleothem deposits.  相似文献   

8.
A calcium carbonate (calcite) bladder calculus was found in the pelvis of an adult female buried in a Mesolithic cave‐tomb on the coast of Sicily; it was dated by 14 C to around 6500 bc . Its chemical composition, which was not known before, was determined by means of Fourier transform–infared microspectroscopy (FT–IR–M) using the high‐pressure diamond cell, a device that makes it possible to analyse a small amount of the sample (1–2 µg). In this way, the analysis of all the laminations of the calculus was performed without destroying the sample. Although calcite was the main component, carbonate apatite was also detected in the nucleus and in a more external layer.  相似文献   

9.
Geochemical and isotopic studies have been undertaken to assess the origin of CO2‐rich waters issuing in the northern part of Portugal. These solutions are hot (76°C) to cold (17°C) Na–HCO3 mineral waters. The δ2H and δ18O signatures of the mineral waters reflect the influence of altitude on meteoric recharge. The lack of an 18O‐shift indicates there has been no high temperature water–rock interaction at depth, corroborating the results of several chemical geothermometers (reservoir temperature of about 120°C). The low 14C activity (up to 9.9 pmC) measured in some of the cold CO2‐rich mineral waters (total dissolved inorganic carbon) is incompatible with the presence of 3H (from 1.7 to 4.1 TU) in those waters, which indicates relatively short subsurface circulation times. The δ13C values of CO2 gas and dissolved inorganic carbon range between ?6‰ and ?1‰ versus Vienna‐Peedee Belemnite, indicating that the total carbon in the recharge waters is being diluted by larger quantities of CO2 (14C‐free) introduced from deep‐seated (upper mantle) sources, masking the 14C‐dating values. The differences in the 87Sr/86Sr ratios of the studied thermal and mineral waters seem to be caused by water–rock interaction with different granitic rocks. Chlorine isotope signatures (?0.4‰ < δ37Cl < +0.4‰ versus standard mean ocean chloride) indicate that Cl in these waters could be derived from mixing of a small amount of igneous Cl from leaching of granitic rocks.  相似文献   

10.
In the North Aegean Domain, Thassos Island contains a Plio‐Pleistocene basin controlled by a large‐scale flat‐ramp extensional system with a potential décollement located at depth within a marble unit. Numerous mineralizations associated with normal faults of Plio‐Pleistocene age are the sign of fluid circulation during extension. Two main generations of fluid flow are recognized, related to Plio‐Pleistocene extension. A first circulation under high‐temperature conditions (about 100–200°C) resulted in dolomitization of marbles near the base of the Plio‐Pleistocene basin. The dolomites are characterized by low δ18O values (down to 11‰ versus Standard Mean Ocean Water). Some cataclastic deformation affected the dolomites. Hydrothermal quartz that crystallized in extension veins above a blind ramp also has low δ18O values (about 13‰). This shows that high‐temperature fluids moved up from the décollement level toward the surface. A second downward circulation of continental waters at near‐surface temperature is documented by calcite veins in fault zones and at the base of the Plio‐Pleistocene basin. These veins have O isotope values relatively constant at about 23–25‰ and C isotope values intermediate between the high δ13C value of the carbonate host rock (about 1–3‰ versus Peedee Belemnite) and the low δ13C value of soil‐derived carbon (?10‰). The calcites associated with the oxidative remobilization of primary sulphide Zn–Pb mineralization of Thassos carbonates have comparable O and C isotope compositions. Hot fluids, within the 100–200°C temperature range, have likely contributed to the weakening of the lower marble unit of Thassos and, thus, to the process of décollement.  相似文献   

11.
Stable nitrogen isotopes have been used to reconstruct infant feeding practices as nursing infants have elevated δ15N ratios compared with their mothers. However, infancy is also a time of rapid growth, which may alter nitrogen isotope diet‐to‐tissue spacing. Several studies have documented a decrease in δ15N during growth in tissues with relatively fast accretion rates. This study investigates the effect that the growth of long bones, via collagen accretion, has on δ15N ratios. Long bones from individuals aged seven to nineteen years were obtained from a protohistoric ossuary in Ontario, Canada. Analysis of juveniles and adolescents permitted the examination of growth in a group who were not also nursing. It is concluded that a nitrogen isotope growth effect is not detectable in bone collagen from juveniles and adolescents, because: (1) δ15N ratios are not significantly different among the epiphyses, metaphyses and diaphysis of a growing long bone; (2) δ15N ratios are not significantly different between faster‐growing versus slower‐growing metaphyses; and (3) δ15N ratios are not significantly different between bones (or areas of a bone) that are still undergoing growth, versus bones that have ceased growing. The relatively slow speed of collagen accretion may explain why a growth effect is not manifested. Ultimately this research lends support to the use of nitrogen isotopes from bone collagen for infant feeding reconstructions. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
S. SAKATA  T. MAEKAWA  S. IGARI  Y. SANO 《Geofluids》2012,12(4):327-335
Previous geochemical studies indicated that most natural gases dissolved in brines in Japan are of microbial origin, consisting of methane produced via carbonate reduction. However, some of those from gas fields in southwest Japan contain methane relatively enriched in 13C, whose origin remains to be clarified. To address this issue, chemical and isotopic analyses were performed on natural gases and brines from the gas fields in Miyazaki and Shizuoka prefectures, southwest Japan. Methane isotopic signatures (δ13C ≈ ?68‰ to ?34‰ VPDB; δ2H ≈ ?183‰ to ?149‰ VSMOW) suggest that these gases are of microbial (formed via carbonate reduction) or of mixed microbial and thermogenic origin. The relatively high δ2H‐CH4 values and their relationship with the δ2H‐H2O values argue against the possibility of their formation via acetate fermentation. The δ13C‐CO2 values (≈?5‰), together with the slope of the correlation between δ2H‐CH4 and δ13C‐CH4δ2H‐CH4δ13C‐CH4 ≈ 1), contradict the possibility of their formation via carbonate reduction followed by partial oxidation by methanotrophs. The 3He/4He ratios of the gases from Miyazaki (≈0.11–1.3 Ra) and their low correlation with δ13C‐CH4 values do not support an abiogenic origin. It is inferred therefore that the high δ13C‐CH4 values of natural gases dissolved in brines from gas fields in southwest Japan are indications of the contribution of thermogenic hydrocarbons, although whether abiogenic hydrocarbons contribute significantly to the gases from Shizuoka requires further investigation. This study has clarified that, for the future exploration of natural gases in southwest Japan, we should adopt the strategies for conventional thermogenic gas accumulations, such as checking the content, type and maturity of organic matter in the underlying sedimentary rocks.  相似文献   

13.
Structural, petrographic, and isotopic data for calcite veins and carbonate host‐rocks from the Sevier thrust front of SW Montana record syntectonic infiltration by H2O‐rich fluids with meteoric oxygen isotope compositions. Multiple generations of calcite veins record protracted fluid flow associated with regional Cretaceous contraction and subsequent Eocene extension. Vein mineralization occurred during single and multiple mineralization events, at times under elevated fluid pressures. Low salinity (Tm = ?0.6°C to +3.6°C, as NaCl equivalent salinities) and low temperature (estimated 50–80°C for Cretaceous veins, 60–80°C for Eocene veins) fluids interacted with wall‐rock carbonates at shallow depths (3–4 km in the Cretaceous, 2–3 km in the Eocene) during deformation. Shear and extensional veins of all ages show significant intra‐ and inter‐vein variation in δ18O and δ13C. Carbonate host‐rocks have a mean δ18OV‐SMOW value of +22.2 ± 3‰ (1σ), and both the Cretaceous veins and Eocene veins have δ18O ranging from values similar to those of the host‐rocks to as low as +5 to +6‰. The variation in vein δ13CV‐PDB of ?1 to approximately +6‰ is attributed to original stratigraphic variation and C isotope exchange with hydrocarbons. Using the estimated temperature ranges for vein formation, fluid (as H2O) δ18O calculated from Cretaceous vein compositions for the Tendoy and Four Eyes Canyon thrust sheets are ?18.5 to ?12.5‰. For the Eocene veins within the Four Eyes Canyon thrust sheet, calculated H2O δ18O values are ?16.3 to ?13.5‰. Fluid–rock exchange was localized along fractures and was likely coincident with hydrocarbon migration. Paleotemperature determinations and stable isotope data for veins are consistent with the infiltration of the foreland thrust sheets by meteoric waters, throughout both Sevier orogenesis and subsequent orogenic collapse. The cessation of the Sevier orogeny was coincident with an evolving paleogeographic landscape associated with the retreat of the Western Interior Seaway and the emergence of the thrust front and foreland basin. Meteoric waters penetrated the foreland carbonate thrust sheets of the Sevier orogeny utilizing an evolving mesoscopic fracture network, which was kinematically related to regional thrust structures. The uncertainty in the temperature estimates for the Cretaceous and Eocene vein formation prevents a more detailed assessment of the temporal evolution in meteoric water δ18O related to changing paleogeography. Meteoric water‐influenced δ18O values calculated here for Cretaceous to Eocene vein‐forming fluids are similar to those previously proposed for surface waters in the Eocene, and those observed for modern‐day precipitation, in this part of the Idaho‐Montana thrust belt.  相似文献   

14.
At Ocean Drilling Program Site 997 in Blake Ridge gas‐hydrate field in West Atlantic, pore‐water studies revealed a pronounced downward depletion of the heavy chlorine isotope to nearly ?4‰δ37Cl at approximately 750 m below sea floor (mbsf) associated with a 10% downward chlorinity decrease. This is one of the stronger 37Cl depletions hitherto reported for marine pore waters. Chlorinity reductions in hydrate‐bearing sediments commonly result from fresh‐water release by hydrate melting. However, in situ measurements at Site 997 suggest that >50% of the chlorinity reduction occurred prior to hydrate dissociation. Modeling the chlorinity profile shows that advection of a strongly 37Cl‐depleted, low‐chlorinity water (506 mm ) from below the drilled sequence can explain the reduction prior to sampling. Fitting the model to the δ37Cl curve yielded an advection rate of 0.18 mm year?1. Diffusive mixing with near‐0‰‐δ37Cl paleo‐seawater with maximum chlorinity at shallow subsurface depths (561 mm at approximately 20 mbsf) produced the smooth, steady trend. Separating that part of the freshening caused by advection and diffusion from that due to hydrate dissociation allowed estimation of average hydrate concentrations of 3.8% of the pore space (up to 24.5% in hydrate‐rich layers; near‐100% in rare massive hydrate layers). The deep‐seated source of the 37Cl‐depleted, low‐chlorinity water remains unknown and might be located below the sedimentary section in the oceanic basement.  相似文献   

15.
Calcite veins in Paleoproterozoic granitoids on the Baltic Shield are the focus of this study. These veins are distinguished by their monomineralic character, unusual thickness and closeness to Neoproterozoic dolerite dykes and therefore have drawn attention. The aim of this study was to define the source of these veins and to unravel their isotopic and chemical nature by carrying out fine‐scale studies. Seven calcite veins covering a depth interval of 50–420 m below the ground surface and composed of breccias or crack‐sealed fillings typically expressing syntaxial growth were sampled and analysed for a variety of physicochemical variables: homogenization temperature (Th) and salinity of fluid inclusions, and stable isotopes (87Sr/86Sr, 13C/12C, 18O/16O), trace‐element concentrations (Fe, Mn, Mg, Sr, rare earth elements) and cathodoluminescence (CL) of the solid phase. The fluid‐inclusion data show that the calcites were precipitated mainly from relatively low‐temperature (Th = 73–106°C) brines (13.4–24.5 wt.% CaCl2), and the 87Sr/86Sr is more radiogenic than expected for Rb‐poor minerals precipitated from Neoproterozoic fluids. These features, together with the distribution of δ13C and δ18O values, provide evidence that the calcite veins are not genetic with the nearby Neoproterozoic dolerite dykes, but are of Paleozoic age and were precipitated from warm brines expressing a rather large variability in salinity. Whereas the isotopic and chemical variables express rather constant average values among the individual veins, they vary considerably on fine‐scale across individual veins. This has implications for understanding processes causing calcite‐rich veins to form and capture trace metals in crystalline bedrock settings.  相似文献   

16.
Br/Cl ratios of hydrothermal fluids are widely used as geochemical tracers in marine hydrothermal systems to prove fluid phase separation processes. However, previous results of the liquid–vapour fractionation of bromine are ambiguous. Here we report new experimental results of the liquid–vapour fractionation of bromine in the system H2O–NaCl–NaBr at 380–450°C and 22.9–41.7 MPa. Our data indicate that bromine is generally more enriched than chlorine in the liquid phase. Calculated exchange coefficients KD(Br‐Cl)liquid‐vapour for the reaction Brvapour + Clliquid = Brliquid + Clvapour are between 0.94 ± 0.08 and 1.66 ± 0.14 within the investigated P–T range. They correlate positively with DClliquid‐vapour and suggest increasing bromine–chlorine fractionation with increasing opening of the liquid–vapour solvus, i.e. increasing distance to the critical curve in the H2O–NaCl system. An empirical fit of the form KD(Br‐Cl)liquid‐vapour = a*ln[b*(DClliquid‐vapour?1) + e1/a] yields a = 0.349 and b = 1.697. Based on this empirical fit and the well‐constrained phase relations in the H2O–NaCl system we calculated the effect of fluid phase separation on the Br/Cl signature of a hydrothermal fluid with initial seawater composition for closed and open adiabatic ascents along the 4.5 and 4.8 J g?1 K?1 isentropes. The calculations indicate that fluid phase separation can significantly alter the Br/Cl ratio in hydrothermal fluids. The predicted Br/Cl evolutions are in accord with the Br/Cl signatures in low‐salinity vent fluids from the 9 to 10°N East Pacific Rise.  相似文献   

17.
Understanding hydrothermal processes during production is critical to optimal geothermal reservoir management and sustainable utilization. This study addresses the hydrothermal (HT) processes in a geothermal research doublet consisting of the injection well E GrSk3/90 and production well Gt GrSk4/05 at the deep geothermal reservoir of Groß Schönebeck (north of Berlin, Germany) during geothermal power production. The reservoir is located between ?4050 to ?4250 m depth in the Lower Permian of the Northeast German Basin. Operational activities such as hydraulic stimulation, production (T = 150°C; Q = ?75 m3 h?1; C = 265 g l?1) and injection (T = 70°C; Q = 75 m3 h?1; C = 265 g l?1) change the HT conditions of the geothermal reservoir. The most significant changes affect temperature, mass concentration and pore pressure. These changes influence fluid density and viscosity as well as rock properties such as porosity, permeability, thermal conductivity and heat capacity. In addition, the geometry and hydraulic properties of hydraulically induced fractures vary during the lifetime of the reservoir. A three‐dimensional reservoir model was developed based on a structural geological model to simulate and understand the complex interaction of such processes. This model includes a full HT coupling of various petrophysical parameters. Specifically, temperature‐dependent thermal conductivity and heat capacity as well as the pressure‐, temperature‐ and mass concentration‐dependent fluid density and viscosity are considered. These parameters were determined by laboratory and field experiments. The effective pressure dependence of matrix permeability is less than 2.3% at our reservoir conditions and therefore can be neglected. The results of a three‐dimensional thermohaline finite‐element simulation of the life cycle performance of this geothermal well doublet indicate the beginning of thermal breakthrough after 3.6 years of utilization. This result is crucial for optimizing reservoir management. Geofluids (2010) 10 , 406–421  相似文献   

18.
In this study, solid‐state 13C magnetic resonance spectroscopy using cross‐polarization combined with high‐powered proton decoupling and magic‐angle sample spinning and Fourier transform infrared spectroscopy using a diamond anvil cell, are employed to give information about the organic functional groups present in charred and non‐charred solid organic residues and to give an insight into the degree of condensation of the chars. Residues were preserved in ceramic vessels recovered from the indigenous settlement of Uitgeest–Groot Dorregeest, dating back to the Roman period. In addition, the application of these solid‐state techniques is used for verification of earlier results obtained in analytical pyrolysis studies and to clarify the relationship between the already thermally degraded charred residues and the controlled heating fragmentation taking place during analytical pyrolysis and direct temperature‐resolved mass spectrometry.  相似文献   

19.
This report describes a defect on the right scapula of a 50 to 60 year old male slave who had been buried extra‐muros in the Le Colombier cemetery of Vaison‐la‐Romaine (5th to 6th century AD) in Vaucluse, France. This injury can only be described as a stress fracture, most likely associated with heavy and persistent use of the humerus in abduction. Other bony defects on the skeleton included early signs of ossification of the glenohumeral joint, slight vertebral discopathy, and osteoarthrosis on the right hip. A relationship between scapular stress fractures and walking devices has been described in the current medical literature, and taking this in consideration, possible aetiologies for this scapular defect include either consistent use of a crutch or routine physical labour. Little information is available on either stress fractures or assisted walking devices in antiquity; therefore this information is a valuable contribution to palaeopathology. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

20.
Groundwater seeps are known to occur in Eckernförde Bay, Baltic Sea. Their discharge rate and dispersion were investigated with a new schlieren technique application, which is able to visualize heterogeneous water parcels with density anomalies down to Δσt = 0.049 on the scale of millimeters. With the use of an inverted funnel, discharged fluids can be captured and the outflow velocity can be determined. Overall, 46 stations could be categorized by three different cases: active vent sites, seep‐influenced sites, and non‐seep sites. New seep locations were discovered, even at shallow near‐shore sites, lacking prominent sediment depression, which indicate submarine springs. The detection of numerous seeps was possible and the groundwater‐influenced area was defined to be approximately 6.3 km2. Flow rates of between 0.05 and 0.71 l m?2 min?1 were measured. A single focused fluid plume, which was not disturbed by the funnel was recorded and revealed a flux of 59.6 ± 20 ml cm?2 min?1 and it was calculated that this single focused plume would be strong enough to produce a flow rate through the funnel of 1.32 ± 0.44 l m?2 min?1. The effect of different seep‐meter funnel sizes is discussed.  相似文献   

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