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391.
J. S. Hanor  J. A. Nunn  Y. Lee 《Geofluids》2004,4(2):152-168
Previous studies of the areal variation in heat flow in the National Petroleum Reserve Alaska (NPRA) support the existence of an active topographically driven regional fluid flow regime in this central part of the North Slope foreland basin. Drilling records and wireline logs for over 30 wells drilled in the NPRA provide additional field information, which can be used to further constrain interpretation of the pattern of regional flow of basinal waters within the NPRA. Hydraulic heads estimated from drilling mud weights show that ground water flow occurs generally from south to north, but with divergence to the north‐east and north‐west away from the central part of the NPRA towards coastal areas of elevated shallow heat flow. Salinities calculated from SP logs range from less than 1 g L?1, to marine values of 35 g L?1, to hypersaline values of over 150 g L?1. The entire upper sedimentary section to a depth of 2 km or more in the eastern part of the NPRA has been preferentially flushed with meteoric water through an area corresponding to the sandiest portion of the Nanushuk group. Deeper areas of low salinity occur within the Sadlerochit and Lisburne sections. The pattern of regional flow in the east is complicated, however, by the presence of a large mass of hypersaline water at depth. It is not known whether these brines are being displaced laterally and upward towards the discharge end of the basin or whether fresher waters are simply riding up over the top. Deep, hypersaline waters also occur in fault slices in the Brooks Range and have survived meteoric flushing. The brines were probably formed at the time of deposition of the Lisburne carbonates. The fluid flow regime to the west is different. Low‐salinity waters may be flowing northward underneath this section through the Ellesmerian section and discharging upward nearer the coast. However, sparse well log control severely limits what can be deduced about the details of flow paths in the central and western parts of the NPRA.  相似文献   
392.
略论晚清乡村社会教化体系的历史变迁   总被引:5,自引:0,他引:5  
Wang X  You Y 《史学月刊》1999,(3):105-113
清朝统治者在实践中确认了“教化为本”的统治原则,且逐渐形成并完善了自己的乡村社会教化体系。清代乡村社会的教化体系乃是一个二元同构性的组织系统,即以保甲制为代表的官方教化组织和形式与以宗族、乡约为代表的非官方教化组织与形式同构而成。鸦片战争后,随着社会结构的变动,乡村教化体系的变迁表现为两个方面:其一是传统乡村教化组织趋于形式;其二是乡村教化的内容开始发生变化。与传统乡村社会的教化体系─—官方与非官方教化组织二元同构性体系──不同,晚清乡村社会的教化体系乃是一个新兴教化体系与旧式教化体系异质并存的复合体。晚清乡村社会的教化体系呈现出多元化的趋向,这首先表现在教化组织形式属性的多元化上。其次还表现为教化主体的多元化。而且,晚清乡村社会教化体系嬗变的历史趋向,是以王朝对于基层社会控制的失控为标志的。清王朝逐渐失去了对乡村社会教化主体的控制,使得乡村社会的教化呈现出一种空前的失范状态。晚清乡村社会教化体系变迁所产生的影响是深远的。它与晚清政府走向灭亡时各项制度的衰落变迁同步进行着,并在相互之间产生着互动,共同构成了王朝灭亡的全部内容。  相似文献   
393.
New carbon crediting and offsetting mechanisms are being developed under the Paris Agreement. Polluters can meet their emission reduction targets by acquiring and retiring carbon offset credits. Globally, most of these credits come from renewable energy sources. However, their additionality is increasingly questionable. Global renewable electricity capacity continues to grow. Greenhouse gas emissions from coal-fired power generation are starting to fall, as governments and organisations pledge to curtail emissions, more capital is mobilised for energy transition, and renewable energy technologies become commercially competitive. The opportunity to earn carbon offset credits is becoming less indispensable to renewable energy development. Aggregate emissions could rise above the baseline level when polluters increase their emission budgets by using carbon credits generated from a renewable energy installation that is part of the baseline scenario. To safeguard environmental integrity, the conditions for including renewable energy in carbon crediting and offsetting schemes should be reconsidered.  相似文献   
394.
A method using the ratios between MnO, Fe2O3 and CoO to differentiate the cobalt sources for Chinese blue‐and‐white porcelain was developed in Oxford in the 1950s using X‐ray fluorescence (XRF) analysis directly on the glaze. In this paper, six blue‐and‐white porcelain sherds from the Luomaqiao kiln were analysed by XRF on the glaze and by scanning electron microscopy with energy‐dispersive spectrometry (SEM‐EDS) in cross‐section. The ratios between MnO, Fe2O3 and CoO calculated by quantitative XRF and EDS analyses are different. The analysis depths for MnO, Fe2O3 and CoO are < 60 μm by XRF analysis. However, the average glaze thickness of samples is > 400 μm, and the MnO, Fe2O3 and CoO mainly remain in the lower layer of the glaze, which is beyond the analysis depths of XRF analysis. The limitations of major and minor quantitative analyses for differentiating cobalt sources are discussed.  相似文献   
395.
X‐ray fluorescence (XRF), X‐ray diffraction (XRD) and Raman spectroscopy were employed to analyse the chemical compositions and phase structures of nine pieces of jade artefacts unearthed from Sujiacun, a Longshan Culture (2400–2000 bce ) site in coastal Shandong, eastern China. The results of the analyses indicated these samples were primarily made from multiple raw mineral materials, including antigorite, actinolite, clinochlore, turquoise and muscovite. No nephrite was recovered from the Sujiacun site. This is strikingly different from other top‐ranking settlements of Longshan Culture, such as Dantu, Liangchengzhen and Xizhufeng, in which nephrite was the main material of jade artefacts. This may reflect the distinctions in the supply system of jade raw materials among different rankings of Longshan period sites. In addition, laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) was used to analyse the composition of the rare earth elements of serpentine jade. These preliminary results were compared with published data on the composition of serpentine jade and it was found that the Sujiacun serpentine jade artefacts were likely sourced from the Taishan jade deposit.  相似文献   
396.
ABSTRACT

State archaeological site files are a critical component of cultural resource management and information management toolkits. Yet, engagement with these datasets for research purposes can be difficult, at best. We address some of the challenges to a synthesis of spatial data from state site files by examining the Woodland period components of Deptford/Cartersville, Swift Creek, and Weeden Island. We also examine time slices of a large set of radiocarbon dates from contexts reported to be associated with Deptford and Swift Creek. Dates are plotted on a map at the same spatial scale as our site files dataset to evaluate time and space simultaneously. This study reveals important gaps in the radiocarbon dataset that can be rectified with strategic sampling. It also supports some long-held ideas about the spatial distribution of Deptford, Swift Creek, and Weeden Island. For example, Weeden Island is demonstrated to be strongly centered on the Alabama and Florida Gulf Coast, whereas Deptford is concentrated on both the Gulf and the Atlantic Coastal Plains.  相似文献   
397.
This article focuses on natural, institutional, and human factors threatening archaeological sites. A methodology is developed for assessing risks to multiple assets on a territorial scale. The methodology consists of hazard assessment, vulnerability assessment, and risk assessment. Hazard assessment involves identifying hazard exposure areas and measuring the frequency and intensity of each hazard. Vulnerability assessment incorporates examining physical, managerial, and contextual vulnerabilities of structures and remains. Geographical information systems are utilised for producing hazard, vulnerability, and risk maps. An overall picture of risks for an entire territory allows decision-makers to make informed decisions at an upstream level to limit further degradation and ensure the preservation of archaeological assets. The methodology was tested by conducting a comprehensive study in ?zmir (Turkey), where 229 archaeological sites located in 21 metropolitan districts were studied. The proposed approach provides the promise of applicability across a range of historic environments.  相似文献   
398.
Y. Hu 《Archaeometry》2018,60(1):144-156
Stable isotope analysis of ancient skeletons has become a routine method and widely used to answer diverse archaeological questions related to the human (animal) diets since the initial study in 1977. However, this study in china is underestimated and much less unknown to international circles considering the infrequent publications in English journals. In this review paper, the research history in China was overviewed shortly and then, the research progresses concerning different research themes, such as the chronological trajectory of human diets, the development and spread of agriculture, the mechanism of animal domestication, human social hierarchy, and so on, were introduced in detail, trying to draw a rough framework of human dietary evolution given the unique Chinese geography and cultures. At last, the potential research directions were also suggested for the future studies.  相似文献   
399.
In this brief response to Sun et al.’s ( 2018 ) comments on our paper, we re‐emphasize that archaeological, chemical and isotopic evidence are all relevant to the discussion about the metal source of the Shang period with highly radiogenic lead isotope ratios. The southern African bronzes have much lower lead contents and quite different lead isotopic signatures than the Shang bronzes. More importantly, there was no metallurgy of any kind in southern Africa before c.200 ce , so southern Africa cannot possibly be the source of Shang bronze, which date to about 1500 to 1000 bce .  相似文献   
400.
Several human groups (from the Neolithic to the Bronze Age) have been analysed in France during the past decade (mainly for C and N stable isotope) as part of research programmes focusing on prehistoric dietary variability. The environment, cultural/social choices or even biological characteristics are among the parameters influencing food acquisition and consumption. This short report presents the first diachronic isotopic results on the palaeodiet in northeastern France. Because of the exceptional archaeological characteristics (human deposits in various positions in pits) of the bone collection from the site of Gougenheim and the surrounding areas (Late Neolithic‐Iron Age, Alsace, France), this assemblage provides a new isotopic dataset to study diet and the potential relationship with social elements or other factors involved in food choices. In order to obtain individual palaeodietary information, carbon and nitrogen stable isotope analyses were performed on 23 adults and 20 immature human bone collagen samples as well as on 25 animal remains. Data were then combined with zooarchaeological and anthropological/archaeological results to reconstruct part of the dietary pattern (i.e. protein consumed) and to detect possible links between the deposit and individual or group social status, defined here by specific mortuary practices. For the Late Neolithic period, isotopic values show, among other things, a wide δ13C range within the female human group, which is statistically lower than the male one. Women probably consumed more diversified food sources, suggesting increased residential mobility. Although body deposits point to the presence of two distinct subgroups, no relationship with animal protein intake was identified. Moreover, the comparison with Iron Age individuals brought to light different dietary patterns between the two periods, indicating that stable isotope values were affected throughout time either by increased millet/legume consumption or environmental/anthropic changes. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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