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1.
G. Hervé  P. Lanos 《Archaeometry》2018,60(4):870-883
We present a new curve of the directional secular variation of the geomagnetic field in Western Europe between 1500 bce and 200 ce . Its computation relies on a Bayesian framework. The fast secular variation during the Late Bronze and Early Iron Ages makes archaeomagnetic dating efficient with a respective precision of 150–200 and 60–100 years during these periods. The Bayesian method also provides posterior date distributions that refine the dating of reference data, especially during the period of the Hallstattian radiocarbon plateau. Archaeomagnetism becomes a valuable alternative to radiocarbon and will help to improve the archaeological chronologies.  相似文献   
2.
The Early Bronze Age was a time of major changes in southern Levantine regions. The spread of urbanisation in the course of the third millennium BC was accompanied by various socio-political transformations, tensions and also violent encounters, even if the evidence for the latter is hard to detect in the archaeological record. The almost complete absence of arrowheads from settlements and tombs in the southern Levant from this period has led to the assumption that combat archery was not employed during the Early Bronze Age.

This paper challenges this orthodoxy using evidence from the southern Levant and beyond, and it concludes that archery was employed in combat activities during the Early Bronze Age, albeit on a small scale that was determined by military considerations.  相似文献   

3.
通过考察多元场对钧瓷文化创意产业知识创造、流动及学习创新的影响发现:①场为主体的地理、社会及文化认知等临近等提供了条件,有助于经验意会及符号知识的获得、共享与传播,有利于思想的交流碰撞及创意萌生;②生产现场、地方关系场、地方社会场与临时性场在钧瓷的学习创新中发挥着不同而又相互补充的作用。生产场推动着集群知识积累和增进,地方关系场促进了行业知识、生产经验及家族核心知识的传播传承,地方社会场形成了地方共享知识信息,而临时场建立起外部通道联系,发挥着更新地方知识库的作用;③地方性的历史文化资源与传统以及地理-社会-文化等临近造就了外围地区文化创意经济的动力,但若未来本地知识更新的机制不够强大,则易产生发展锁定,这是需要未来引起关注的问题。  相似文献   
4.
Development studies employs theories, tools and methods often found in geography, including the international field trip to a “developing” country. In 2013 and 2014, I led a two-week trip to Ethiopia. To better comprehend the effects of “the field” on students’ learning, I introduced an assessed reflexive field diary to understand what the field trip experience teaches students about themselves and their relationship to the field. In this paper, I present critical reflections on “the field” that speak to a provocative concept – “the tropics”. These reflections illuminate prevailing challenges in the study and practice of development and suggest a way forward.  相似文献   
5.
The French–Portuguese Ethnological Mission to Portuguese Timor (1966/1969) financed by French and Portuguese research bodies and initially directed by Louis Berthe was the first mission that conducted lengthy and thorough ethnographic research in East Timor vernaculars and with East Timorese communities. Using personal and scientific archives, printed and oral sources, this article analyses the mission’s background, the role of Ruy Cinatti (a Portuguese poet, former colonial official in Timor and anthropologist trained in Oxford) in its launch, and its political and scientific context. The mission, undertaken during the Portuguese late colonial period and subject to the Portuguese authorities’ approval and surveillance, marked East Timor as a site of anthropological inquiry into the Anthropology of European tradition produced in Southeast Asia, affiliated to post-war structuralism. This case study throws light on individual agency, Portugal’s shortcomings in modern anthropology training, the international competition for Portuguese Timor as part of the Indonesian “field of ethnological study” and the transnational connections in its construction in the era of decolonization.  相似文献   
6.
晚清至民国时期陕西基督教宣教区研究   总被引:3,自引:0,他引:3  
功能文化区作为一种重要的文化区类型,目前在我国历史文化地理学研究中并没有受到重视。究其原因,是因为中国传统文化的地域分布多以形式文化区,或是感觉文化区的形态出现,很少能构成真正意义上的功能文化区。本文则通过对晚清至民国时期陕西基督教宣教区进行个案研究,指出以功能文化区形式出现的宣教区,其空间结构特征,一方面受制于中国传统的文化地域格局,另一方面,则与各差会在陕西发展的历史过程与权力关系有着密切的关系。  相似文献   
7.
A typology of artificial rock hollows and tentative identification of their functions is founded upon study of recent practices at Sukur. Five stages of development of equipment for grinding grain are identified and shown, using field archaeological evidence, to constitute a sequence of historical phases that extends from the Neolithic or early Iron Age to the present. The development of other types of hollows is related to this sequence. Ethnographic data are employed to estimate the use lives of grain grinding hollows, which are interpreted in terms of woman-centered familial grain-grinding units. The evidence suggests that prior to ca. AD 1600 the population density averaged two orders of magnitude less than in recent times—with important implications for regional culture history. This exploratory study demonstrates the potential of artificial hollows as evidence for the study of prehistory, culture and demographic history, and the history of landscape in Africa and beyond.  相似文献   
8.
F. Wendler  A. Okamoto  P. Blum 《Geofluids》2016,16(2):211-230
Mineral precipitation in an open fracture plays a crucial role in the evolution of fracture permeability in rocks, and the microstructural development and precipitation rates are closely linked to fluid composition, the kind of host rock as well as temperature and pressure. In this study, we develop a continuum thermodynamic model to understand polycrystalline growth of quartz aggregates from the rock surface. The adapted multiphase‐field model takes into consideration both the absolute growth rate as a function of the driving force of the reaction (free energy differences between solid and liquid phases), and the equilibrium crystal shape (Wulff shape). In addition, we realize the anisotropic shape of the quartz crystal by introducing relative growth rates of the facets. The missing parameters of the model, including surface energy and relative growth rates, are determined by detailed analysis of the crystal shapes and crystallographic orientation of polycrystalline quartz aggregates in veins synthesized in previous hydrothermal experiments. The growth simulations were carried out for a single crystal and for grain aggregates from a rock surface. The single crystal simulation reveals the importance of crystal facetting on the growth rate; for example, growth velocity in the c‐axis direction drops by a factor of ~9 when the faceting is complete. The textures produced by the polycrystal simulations are similar to those observed in the hydrothermal experiments, including the number of surviving grains and crystallographic preferred orientations as a function of the distance from the rock wall. Our model and the methods to define its parameters provide a basis for further investigation of fracture sealing under varying conditions.  相似文献   
9.
We used hydrologic models to explore the potential linkages between oil‐field brine reinjection and increases in earthquake frequency (up to Md 3.26) in southeastern New Mexico and to assess different injection management scenarios aimed at reducing the risk of triggered seismicity. Our analysis focuses on saline water reinjection into the basal Ellenburger Group beneath the Dagger Draw Oil field, Permian Basin. Increased seismic frequency (>Md 2) began in 2001, 5 years after peak injection, at an average depth of 11 km within the basement 15 km to the west of the reinjection wells. We considered several scenarios including assigning an effective or bulk permeability value to the crystalline basement, including a conductive fault zone surrounded by tighter crystalline basement rocks, and allowing permeability to decay with depth. We initially adopted a 7 m (0.07 MPa) head increase as the threshold for triggered seismicity. Only two scenarios produced excess heads of 7m five years after peak injection. In the first, a hydraulic diffusivity of 0.1 m2 s?1 was assigned to the crystalline basement. In the second, a hydraulic diffusivity of 0.3 m2 s?1 was assigned to a conductive fault zone. If we had considered a wider range of threshold excess heads to be between 1 and 60 m, then the range of acceptable hydraulic diffusivities would have increased (between 0.1–0.01 m2 s?1 and 1–0.1 m2 s?1 for the bulk and fault zone scenarios, respectively). A permeability–depth decay model would have also satisfied the 5‐year time lag criterion. We also tested several injection management scenarios including redistributing injection volumes between various wells and lowering the total volume of injected fluids. Scenarios that reduced computed excess heads by over 50% within the crystalline basement resulted from reducing the total volume of reinjected fluids by a factor of 2 or more.  相似文献   
10.
在先秦时期的中原,基地、墓葬的头向以及夫妻合葬墓中左右方位的选择,不断被赋予礼制的内涵,体现了我国古代丧葬制度不断发展、演变的过程。尤其是到周代,丧葬制度趋于完备。其中的茔域与方位之制,成为古代礼制的重要组成部分。  相似文献   
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