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51.
Since the 1960s the analysis of small-scale surface processes has been the dominant approach in geomorphology, the previous focus on regional-scale landscape evolution having been largely abandoned as a result of the lack of knowledge of processes and process rates at the relevant temporal and spatial scales. It has recently been acknowledged that small-scale, surface process geomorphology alone is unable to provide an understanding of long-term landscape development, both because of the significance of tectonics, and because of the important role of contingency at the large temporal and spatial scales involved. But the major advances in geochronological techniques and numerical modelling of landscape evolution that are now revolutionizing our understanding of long-standing questions of landscape evolution have been largely developed and applied by researchers from outside the traditional geomorphology community. As a result, two distinct communities of researchers have emerged concerned with different scales of landform analysis, but the progress of geomorphology will be best served by greater interaction between them.  相似文献   
52.
In this paper, the characterization of Roman amphorae from the Porto dos Cacos (PC) and Quinta do Rouxinol (QR) workshops, in the Tagus estuary, dating to a period between the 1st and 5th century AD was carried out on the basis of instrumental neutron activation analysis data on 260 amphorae fragments, together with mineralogical compositional studies obtained by X-ray diffraction.  相似文献   
53.
In the last few years virtual anthropology has been used to solve different problems that could not be properly addressed using a traditional anthropological approach. Mainly when dealing with mummies or embalmed bodies, the virtual approach is the only solution to carry out a detailed analysis of the skeleton without jeopardizing the integrity of the physical remains.  相似文献   
54.
<正>陕西唐陵大遗址保护项目的考古工作荣获2007~2008年度全国田野考古一等奖。这是国家文物局和考古学界对我们工作成绩的肯定与鼓励,也是我院田野考古工作者开拓创新、辛勤工作的结果。以下将唐陵考古工作中的思路、方法、措施以及得失作以介绍,以期得到考古界同仁的指教。  相似文献   
55.
南京市区就业空间布局研究   总被引:5,自引:0,他引:5  
王波  甄峰 《人文地理》2011,26(4):58-65
本文采取就业密度分析方法,对南京市区就业空间布局进行实证研究。在南京市区现有11个区的基础上将南京市区划分为159个研究单元。依据2005年南京市1%人口抽样调查资料中"区县层面"分行业就业数据,以及2006年南京市用地现状图,修正匹配得到各个研究单元制造业、服务业、商业金融业及总的就业密度值。并运用Arcgis软件对就业密度值进行核密度分析以及3D模拟,分析南京市区制造业、服务业以及总就业的空间布局特征及原因机制。  相似文献   
56.
J. P. FAIRLEY 《Geofluids》2009,9(2):153-166
Previous studies have shown that most hydrothermal systems discharging at the land surface are associated with faulting, and that the location, temperature and rate of discharge of these systems are controlled by the geometry and style of the controlling fault(s). Unfortunately, the transport of heat and fluid in fault-controlled hydrothermal systems is difficult to model realistically; although heterogeneity and anisotropy are assumed to place important controls on flow in faults, few data or observations are available to constrain the distribution of hydraulic properties within active faults. Here, analytical and numerical models are combined with geostatistical models of spatially varying hydraulic properties to model the flow of heat and fluid in the Borax Lake fault of south-east Oregon, USA. A geometric mean permeability within the fault of 7 × 10−14 m2 with 2× vertical/horizontal anisotropy in correlation length scale is shown to give the closest match to field observations. Furthermore, the simulations demonstrate that continuity of flow paths is an important factor in reproducing the observed behavior. In addition to providing some insight into possible spatial distributions of hydraulic properties at the Borax Lake site, the study highlights one potential avenue for integrating field observations with simulation results in order to gain greater understanding of fluid flow in faults and fault-controlled hydrothermal and petroleum reservoirs.  相似文献   
57.
This paper considers the impact of distance to polling station upon electoral turnout. Using polling station level data from a London borough, it examines three types of election – parliamentary, European and local elections – over a twenty year period. The UK is notable among western liberal democracies for its relatively large turnout gap – the percentage point difference between turnout at elections for the Westminster parliament compared to that for other institutions, including local councils and the supra-national European parliament. This research considers the hypothesis that in high information, high salience elections for the national parliament the costs of voting associated with travelling to a polling station to vote in person are perceived as either low or insignificant but that in low information, low salience elections, those costs are perceived as higher and may act as a deterrent upon voting. A series of multi-level models consider the relationships between the dependent variable, percentage turnout, and a range of independent variables, including socio-economic characteristics, marginality as well as the spatial context. We show that there is indeed a relationship between distance and voter turnout, and other spatial and contextual variables, which are stronger for the lower salience European and local elections than for the higher salience national elections. Hence we conclude that the local geography of the polling station can have a significant impact on voter turnout and that there should be a more strategic approach to the siting of polling stations.  相似文献   
58.
The Central Anatolian Volcanic Province (CAVP) in Turkey preserves widespread deposits of Quaternary tephra, presently associated with a small but growing number of Paleolithic archaeological sites. We use multivariate analyses of the abundances of a suite of nine major and minor element oxides determined by electron probe microanalysis. From these data, we construct a classificatory model for correlating distal tephra to one of five volcanic edifices or eruptive phases within the CAVP. Application of this model to distal deposits of primary tephra-fall and reworked tuffaceous sediments from the archaeological sites of Körkuyu and Kaletepe Deresi 3 indicates Late to possibly Early Pleistocene ages for the artifact assemblages there, and provides a fundamental tephrostratigraphic framework to examine spatial and temporal variation in hominin behavior comparable to that of other regions, such as eastern Africa.  相似文献   
59.
A methodology is described by which spatial patterns of land use were reconstructed from pollen analyses on anthropogenic sediments at a recently excavated early Neolithic timber ‘hall’ in north east Scotland. The anthropogenic sediments were from a deep, small diameter pit within the building. They present numerous taphonomic and interpretative challenges to the analyst, but from this type of deposit, the power to estimate quantitatively the vegetation structure around the archaeological site makes such difficult deposits very significant. A rigorous methodology is firstly described, therefore, by which confidence in ecological interpretation can be established. Secondly, the source of pollen in the deposit is evaluated. Thirdly, the possible pollen source area and structure of the surrounding vegetation are estimated by quantitative simulation modelling. Finally, these analyses are compared with region-scale pollen analyses from nearby conventional wetland deposits with much larger pollen source areas. The pollen assemblages recovered probably reflect land uses adjacent to the ‘hall’ and up to 2.5 km around. Cereal cultivation was the most important land use immediately around the ‘hall’, possibly grown between stands of scrub Corylus (hazel) woodland. These intensive but local-scale land uses cannot be discerned in region-scale pollen analyses.  相似文献   
60.
The influence of relief, as well as other environmental features such as soils or the hydrological regime, on prehistoric settlement patterns is commonly accepted. Settlement patterns and preferences changed over time in different areas, so it is difficult to formulate general rules of human behaviour throughout history. In lowland areas of the temperate zone, which lack radical relief changes and have widespread access to water resources, specific settlement preferences and significant changes in these preferences are difficult to interpret.New methods developed to address the problem of the settlement transformations as a result of prehistoric settlement and economic processes using multivariate statistics have been adapted for the middle part of the Great Poland Lowland. In this region, data from the Polish Archaeological Record Project database have been used.Models of the dependence between geomorphological features and settlement intensity form the basis for estimating changes in prehistoric settlements. The degree of preference (or avoidance) is a nonparametric function of the number of archaeological sites observed in the area relative to the number of sites expected from a completely random pattern. The most crucial factors for settlement are distance to plateau edges, distance to water bodies, and the wetness index. The results show that the entire investigated area is more or less suitable for settlement, but the most occupied terrains are the areas near plateau edges.  相似文献   
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