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1.
Hip fractures have high incidence rates in many current groups and are associated with high morbidity, mortality, and considerable expenditure. Although hip fractures associated with significant traumatic events can occur at any age, many hip fractures occur in older adults. To date, few hip fractures have been reported from archaeological skeletal material, and a number of hypotheses have been suggested for this. This research presents a comprehensive assessment of hip fractures in archaeological bone; 1597 adult (18+ years) skeletons from eight urban post‐medieval sites from England dating from the 18th and 19th centuries were recorded, and contemporary medical texts reviewed. This adult sample included 834 males and 652 females as well as 11 persons of undetermined sex. Ways of classifying and describing fractures in the clinical literature were reviewed and a methodology applicable to paleopathology determined. Of this sample, 15 (0.94%) had fractures in the femoral neck or intertrochanteric area: nine males, four females, and two individuals of undetermined sex. The numbers of fractures in males were interesting and most likely represent examples of accidental trauma as well as osteoporosis‐related fractures, the latter receiving growing awareness in recent clinical literature. Overall there was an age‐related trend with more individuals aged 50+ years with fractures than in other age categories. Underlying osteoporosis was potentially a complicating factor in five individuals and was likely associated with a vitamin D deficiency osteomalacia and a metastatic neoplastic condition in a further two cases. Fractures occurring close to the time of death and healed fractures were observed, indicating that the risk of mortality following this trauma was not consistent across this 18th and 19th century sample. Skeletal and historical evidence presented in this study indicate that the impact of hip fracture injuries varied, with survival likely linked to the fracture type. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

2.
Water acidification follows CO2 injection and leads to reactive fluid transport through pores and rock fractures, with potential implications to reservoirs and wells in CO2 geologic storage and enhanced oil recovery. Kinetic rate laws for dissolution reactions in calcite and anorthite are combined with the Navier‐Stokes law and advection–diffusion transport to perform geometry‐coupled numerical simulations in order to study the evolution of chemical reactions, species concentration, and fracture morphology. Results are summarized as a function of two dimensionless parameters: the Damköhler number Da which is the ratio between advection and reaction times, and the transverse Peclet number Pe defined as the ratio between the time for diffusion across the fracture and the time for advection along the fracture. Reactant species are readily consumed near the inlet in a carbonate reservoir when the flow velocity is low (low transverse Peclet number and Da > 10?1). At high flow velocities, diffusion fails to homogenize the concentration field across the fracture (high transverse Peclet number Pe > 10?1). When the reaction rate is low as in anorthite reservoirs (Da < 10?1), reactant species are more readily transported toward the outlet. At a given Peclet number, a lower Damköhler number causes the flow channel to experience a more uniform aperture enlargement along the length of the fracture. When the length‐to‐aperture ratio is sufficiently large, say l/d > 30, the system response resembles the solution for 1D reactive fluid transport. A decreased length‐to‐aperture ratio slows the diffusive transport of reactant species to the mineral fracture surface, and analyses of fracture networks must take into consideration both the length and slenderness of individual fractures in addition to Pe and Da numbers.  相似文献   

3.
An understanding of fluid flow, mass transport and isotopic exchange in fractured rock is required to understand the origin of several geological processes including hydrothermal mineral deposits. The numerical model HydroGeoSphere simulates 3D advection, molecular diffusion, mechanical dispersion and isotopic exchange in a discretely fractured porous media, and can be used to better understand the processes of mass transport and isotopic exchange in fractured rocks. Study of 18O isopleth patterns for different types of fractures and fracture networks with a range of structural complexity and hydraulic properties shows that fracture properties and geometry control mass transport and isotopic exchange. The hydraulic properties, as well as the density, spacing, and connectivity of fractures determine the isotopic patterns. Asymmetries in the geometry of oxygen isotope patterns could be used to determine the direction of hydrothermal fluid flow.  相似文献   

4.
A growing awareness of the problems caused by osteoporosis‐related fractures has led to increased investigation of the condition in past populations. The present study seeks to examine the ways in which osteoporosis‐related fractures may be explored through different approaches; modern clinical information, historical records of fractures and analysis of archaeological bone may provide fuller information on the condition. The three types of fractures upon which this study focuses are fractures of the femoral neck, Colles' fractures and vertebral compression fractures. The results of the investigation clearly demonstrate the way in which the various sources produce a slightly different picture of the condition. The archaeological significance of the different types of fractures was found to be the reverse of that which would be suspected in the light of information derived from historical sources and the clinical literature. To date vertebral crush fractures have been the most commonly found osteoporosis‐related fracture in archaeological material, but their significance to people in the past is likely to have been minimal. In contrast hip fractures have rarely been reported from archaeological bone material, but historical information makes it clear they were well known, and knowledge derived from clinical sources emphasizes the serious consequences of such a fracture for the affected individuals. The results indicate the value of undertaking a multi‐disciplinary approach where possible. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

5.
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   

6.
The Devonian Antrim Shale is an organic‐rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well‐developed network of major, through‐going vertical fractures controls reservoir‐scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ13C values (+34 to ?41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ13C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ13C values (13C values between ?10 and ?30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of 13C‐rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture‐fill cements. The δ18O values in both formation waters and calcite cements increase with depth in the basin (?12 to ?4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture‐fill cements from outcrop samples have δ13C values between ?41 and ?15‰ PDB. In contrast, most cement in cores have δ13C values between +15 and +34‰ PDB. Radiocarbon and 230Th dating of fracture‐fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.  相似文献   

7.
The relationship between fracturing and fracture filling in opening‐mode fractures in the Triassic Buntsandstein in the Lower Saxony Basin (LSB; NW Germany) has been studied by an integration of petrographic and structural analysis of core samples, strontium isotope analysis and microthermometry on fluid inclusions. This revealed the relationship between the timing of the fracturing and the precipitation of different mineral phases in the fractures by constraining the precipitation conditions and considering the possible fluid transport mechanisms. The core was studied from four different boreholes, located in different structural settings across the LSB. In the core samples from the four boreholes, fractures filled with calcite, quartz and anhydrite were found, in addition to pore‐filling calcite cementation. In boreholes 2 and 3, calcite‐filled fractures have a fibrous microstructure whereas in borehole 1, fractures are filled with elongate‐blocky calcite crystals. Anhydrite‐filled fractures have, in all samples, a blocky to elongate‐blocky microstructure. Fractures that are filled with quartz are observed in borehole 2 only where the quartz crystals are ‘stretched’ with an elongated habit. Fluid inclusion microthermometry of fracturing‐filling quartz crystals showed that quartz precipitation took place at temperatures of at least 140°C, from a fluid with NaCl–CaCl2–H2O composition. Melting phases are meta‐stable and suggest growth from high salinity formation water. Strontium isotopes, measured in leached host rock, indicate that, in boreholes 2 and 3, the fluid which precipitated the calcite cements and calcite‐filled fractures is most likely locally derived whereas in borehole 1, the 87Sr/86Sr ratios from the pore‐filling cements and in the elongate‐blocky calcite‐filled fracture can only be explained by mixing with externally derived fluids. The elongate‐blocky anhydrite‐filled fractures, present in boreholes 1, 3 and 4, precipitated from a mixture of locally derived pore fluids and a significant quantity of fluid with a lower, less radiogenic, 87Sr/86Sr ratio. Taking into account the structural evolution of the basin and accompanying salt tectonics, it is likely that the underlying Zechstein is a source for the less radiogenic fluids. Based on the samples in the LSB, it is probable that fibrous fracture fillings in sedimentary rocks most likely developed from locally derived pore fluids whereas elongate‐blocky fracture fillings with smooth walls developed from externally derived pore fluids.  相似文献   

8.
Injuries classified as parry fractures, normally the result of a direct blow when the forearm is raised to shield the face, are significant in bioarcheological interpretations because the parry fracture is perceived as an indicator of interpersonal (or extramural) violence. It is therefore necessary that these injuries be correctly identified in order to properly interpret the trauma pattern and its social implications for abuse, gender and power relations among ancient people. Common acute forearm fractures are reviewed here and quantitative guidelines that define the parry fracture configuration are presented. The parry criteria include: (1) an absence of radial involvement, (2) a transverse fracture line, (3) a location below the midshaft (<0.5 adjusted distance to the lesion's center), and (4) either minor unalignment (<10°) in any plane or horizontal apposition from the diaphysis (<50%). A sample of 278 adults from northern Sudan dated to the Nubian Bronze Age (ca. 2500–1500 BC) contained 38 individuals with forearm fractures. Of these fractures, 21 out of the 28 ulna injuries were identified as parry fractures using the parry criteria. Fewer females suffered from parry fractures than when ulna injuries were identified by location on the ulna alone. The use of the parry criteria may not always affect the results significantly, but here interpersonal violence directed against women and amongst ancient Nubians was found to be less prevalent than implied in earlier studies. The absence of perimortem parry fractures suggests that the Kermans interred within mass burials were not physically forced to their graves. Chronic ulna stress fractures associated with sports and habitual activities must also be considered as a differential diagnosis of this injury.  相似文献   

9.
In granitic rocks, fracture networks typically provide pathways for groundwater flow and solute transport that need to be understood to assess the long‐term performance of deep underground storage or disposal facilities such as radioactive waste repositories. However, relatively little is known about the long‐term processes of fracturing and/or the longevity of flow paths (FP) in granitic rocks distributed within orogenic belts. To clarify these issues, Japanese plutons of different ages and in situ fractures in granite at the Mizunami Underground Research Laboratory (MIU) located in central Japan were studied. Detailed structural characterization and geochemical analysis of in situ fracture fillings sampled from a depth of 300 m were carried out to clarify the relationship between fracturing and mineral infilling processes. Different plutons show identical episodes of fracturing and fracture filling, consisting of: brittle tensile fracturing, due to decreasing temperature through the ductile–brittle transition after plutonic intrusion (Stage I); relatively rapid uplifting (ca. a few mm/year) accompanied by hydrothermal water circulation, which produced uncrushed layered mineral fillings (Stage II); and a period of low‐temperature meteoric water circulation following exposure after uplift (Stage III). The parageneses of carbonate mineral fracture fillings and their carbon isotopic compositions (14C, δ13C) show that there were distinct episodes of carbonate mineral precipitation during the rapid uplifting of a pluton. The carbonate minerals that formed during each episode incorporated carbon from a distinct source. The evolution of fillings identified here enables development of a specific model of fracturing and persistence of fluid‐conducting systems in the plutons of the orogenic field.  相似文献   

10.
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   

11.
12.
The spine can provide a large amount of information about an individual's physical condition and possible lifestyle through palaeopathological investigations. The aim of this research was to study spinal diseases among Greco‐Roman ancient Egyptians from Bahriyah Oasis, and to compare them with those from Giza of the Old Kingdom. The material used in the study included 809 single vertebrae and 77 adult sacra of ancient Egyptians from the Greco‐Roman period (332–30 BC) that were excavated from Bahriyah Oasis. The spinal elements were examined for pathological conditions, degenerative diseases, trauma, congenital abnormalities, infectious diseases and neoplasms. The most common lesions of the spine were those due to degenerative processes. The articular facets were more affected than the vertebral bodies. Compression fractures of the bodies, mostly due to osteoporosis, were found in 1.44% and 5.07% of thoracic and lumbar vertebrae respectively. The percentage of spina bifida occulta among ancient Egyptians from Bahriyah Oasis was 62.33%, while among those from Giza was only 3.33%. Few cases of lumbar spondylolysis and one case of DISH were recorded. No cases of infectious or neoplastic diseases were found. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

13.
This study focuses on an old male skeleton, which shows severe fractures of the right femur and of the left tibia and fibula. The skeleton, complete and in a good condition of preservation, comes from a Sardinian osteological collection (from the beginning of 1900 AD) with known age, sex and life‐activity. The features of the fractures and pattern of joint disease, enthesis development and enthesopathies have been studied in order to ascertain a possible cause for these traumatic events, the functional implications for postural and locomotory behavior and, finally, the eventual evidence of medical treatment. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

14.
Samples from the Amposta Marino C2 well (Amposta oil field) have been investigated in order to understand the origin of fractures and porosity and to reconstruct the fluid flow history of the basin prior, during and after oil migration. Three main types of fracture systems and four types of calcite cements have been identified. Fracture types A and B are totally filled by calcite cement 1 (CC1) and 2 (CC2), respectively; fracture type A corresponds to pre‐Alpine structures, while type B is attributed to fractures developed during the Alpine compression (late Eocene‐early Oligocene). The oxygen, carbon and strontium isotope compositions of CC2 are close to those of the host‐rock, suggesting a high degree of fluid‐rock interaction, and therefore a relatively closed palaeohydrogeological system. Fracture type C, developed during the Neogene extension and enlarged by subaerial exposure, tend to be filled with reddish (CS3r) and greenish (CS3g) microspar calcite sediment and blocky calcite cement type 4 (CC4), and postdated by kaolinite, pyrite, barite and oil. The CS3 generation records lower oxygen and carbon isotopic compositions and higher 87Sr/86Sr ratios than the host‐limestones. These CS3 karstic infillings recrystallized early within evolved‐meteoric waters having very little interaction with the host‐rock. Blocky calcite cement type 4 (CC4 generation) has the lowest oxygen isotope ratio and the most radiogenic 87Sr/86Sr values, indicating low fluid‐rock interaction. The increasingly open palaeohydrogeological system was dominated by migration of hot brines with elevated oxygen isotope ratios into the buried karstic system. The main oil emplacement in the Amposta reservoir occurred after the CC4 event, closely related to the Neogene extensional fractures. Corrosion of CC4 (blocky calcite cement type 4) occurred prior to (or during) petroleum charge, possibly related to kaolinite precipitation from relatively acidic fluids. Barite and pyrite precipitation occurred after this corrosion. The sulphur source associated with the late precipitation of pyrite was likely related to isotopically light sulphur expelled, e.g. as sulphide, from the petroleum source rock (Ascla Fm). Geofluids (2010) 10 , 314–333  相似文献   

15.
The burial of a child of two years of age from the 4th century site of Lisieux‐Michelet (Calvados, France) was examined for bone hyperplasia and a variety of mechanical deformations recognized in association with skeletal trauma. Results of DNA analysis of bone using the PCR method identified this child as female. Microscopic features of the teeth (interglobular dentine) and a sample taken from the tibia conclusively determined that this child suffered from vitamin D‐resistant rickets and possibly X‐linked hypophosphataemic rickets as its most common form of occurrence. In addition, evidence for child abuse is suspected based on the presence of cranial and tooth fractures and the appearance of successive plaque‐like endocranial (meningeal) appositions. This is the first palaeopathological report of child abuse in antiquity. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

16.
The archaeological site at PRERESA (Madrid, Spain) has been dated to 84 ± 5.6 ka by optically stimulated luminescence (OSL) (MIS 5a). An area 255 m2 was excavated and 754 lithic pieces were recovered, as well as a large amount of micro and macro vertebrate remains, including proboscidean bones. The aim of this paper is to outline the results of the taphonomic study of these remains. The identification of cut marks on a number of the bones recovered strengthens the theory that the exploitation of extremely large mammals was more than just a marginal practice before the Upper Palaeolithic. Additionally, the identification of green-bone fractures and percussion marks confirm for the first time, that the bone marrow of these taxa was also consumed. Few other cases of this practice have been identified, firstly because obtaining this substance would not be an easy matter, and secondly because similar nutritional needs can also be met by the consumption of brain matter, which is easier to acquire.  相似文献   

17.
Occipitalization of the atlas was observed in two adult female skeletons from the Greek colonial site of Apollonia Pontica (5th to 3rd centuries BC), located on the Bulgarian Black Sea coast. Representing a rare congenital anomaly of the atlanto‐occipital junction, this condition has been documented in very few skeletal remains from Classical antiquity. Postmortem damage to one of the specimens prevented an evaluation of its clinical significance. The dimensions of the second specimen, however, suggest that the affected individual may have experienced some neurological symptoms associated with her condition. The burial of the two females in close proximity to one another raises the possibility that they may have been biologically related. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

18.
Three circumscribed depressed fractures were found on the skull of an adolescent boy recovered from a primary intramural burial at the Chalcolithic site of Shiqmim, northern Negev, Israel dated to (∼4500–3200 BCE). The fractures were located on the left side and back of the skull. They are circular in outline and have sharp margins containing numerous small bone fragments. These indicate that the skull was fractured when the bone was still fresh and were the probable cause of death. The location of the fractured areas is typical of blows inflicted by a right‐handed individual in face‐to‐face conflict. The size and shape of the fractures, suggests that they were inflicted by a blunt instrument, possibly a mace head. The absence of any signs of healing or infection indicates that all fractures occurred within a short space of time and resulted in death. Neither biological characteristics nor burial pattern show any unique features that distinguish this individual from others recovered at this site. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

19.
Investigations into the development of weapon systems are increasingly important in archaeological debates about human evolution and behavioural variability. ‘Diagnostic’ impact fractures are key, but controversial, lines of evidence commonly used in such investigations. In 2009 a series of experiments was initiated to investigate the processes associated with macrofracture formation specifically focussing on the taphonomic factors affecting the formation of ‘diagnostic’ impact fractures (DIFs). This paper adds to that experimental data set with macrofracture results from recent knapping experiments investigating rock type variability and DIF formation. These results show that rock type variation plays less of a role in DIF formation than variables related to use and lithic taphonomy. The collective results of this experimental series show that the location, co-occurrence, type and proximity to retouch on a tool are all important means of distinguishing between weapon and non-weapon related DIFs. Collectively these macrofracture patterns are more important in diagnosing weapon components than any one ‘diagnostic’ impact fracture is alone. Overall, these experimental studies are showing that background ‘noise’ in the form of non-hunting related impact fractures, exists in many macrofracture results and that much work remains in securing the analytical robusticity of the method. The paper concludes that the macrofracture method is not a stand-alone method, but when used with caution and in conjunction with other lines of evidence it is a useful, time-efficient, tool for generating assemblage-level use-trace data.  相似文献   

20.
Saltpetre (KNO3) manufacture was a principal monopoly industry in early Modern India when the United Kingdom governed the social and economic systems. The process represented microbial transformation of excrementitious livestock and human wastes deposited around habitats, resulting in formation of salt efflorescence at an economic scale. Low caste people collected these wastes for extraction and production of rough saltpetre under the administrative control of British India. Stable isotope composition (δ15N and δ18O) was used to trace details of the microbial transformation processes, often involving the isotopic fractionation of nitrogen and oxygen. Marked elevation in δ15N and δ18O values for nitrates in soils and deposits, relative to those of primary organic nitrogen in diets and water sources, characterizes the unique processes of historic saltpetre manufacture in British India.  相似文献   

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