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1.
When Bolivian and Paraguayan leaders entered into war over the contested Chaco Boreal in 1932, they unleashed powerful, violent forces that would dramatically alter history. Understanding the Chaco War as the most pivotal event in Bolivia’s modern history, this article seeks to clarify the modernisation programme that had been underway in Bolivia during the 1920s. Reforms marked the decade and intersected with and accentuated a tense political environment. The political dynamic of the years prior to the outbreak of war showed how fragile the Bolivian system was and how the global economy further eroded the government’s manoeuvrability to avoid war.  相似文献   
2.
“卡夫丁峡谷”问题的当代性探析   总被引:1,自引:0,他引:1  
“卡夫丁峡谷”问题是马克思在晚年分析俄国社会发展道路时提出的。“卡夫丁峡谷”问题的当代性在于它为我们提供了了解社会历史发展规律的视角,为落后国家实现社会跳跃式发展提供了理论指导,也为我们研究社会历史问题提供了新的视角。  相似文献   
3.
Current research on Chaco Canyon and its surrounding outlier communities is at an important juncture. Rather than trying to argue for the presence or absence of complexity, archaeologists working in the area are asking different questions, especially how Chacoan political, economic, ritual, and social organization were structured. These lines of inquiry do not attempt to pigeonhole Chaco into traditional neoevolutionary types, but instead seek to understand the historical trajectory that led to the construction of monumental architecture in Chaco Canyon and a large part of the northern Southwest in the 10th through 12th centuries. This review discusses the conclusions of current research at Chaco including definitions of the Chaco region, recent fieldwork, histories of Chaco archaeology, chronology, paleoenvironmental reconstruction, demography, political organization, outlier communities, economic organization, social organization, ritual, violence, and the post-Chacoan reorganization. Although many issues are hotly debated, there is a growing concensus that power was not based in a centralized political organization and that ritual organization was a key factor in the replication of Chacoan architecture across a vast regional landscape. Exactly how ritual, social, and political organization intersected is a central question for Chaco scholars. The resolution of this problem will prove to be of interest to all archaeologists working with intermediate societies across the globe.  相似文献   
4.
The Bonito Phase (ca. AD 860–1140) in Chaco Canyon is widely recognized as one of the primary sources of information about emergent social complexity in prehispanic North America. Large masonry buildings called “great houses,” such as Pueblo Bonito, are iconic symbols of the rapid rise of a powerful society based on the ability to harness labor to prolonged construction projects. It is clear that the political forces at work during the Bonito Phase had an agricultural foundation, presumably in the financing of construction through food surpluses, but the actual nature of farming in Chaco is surprisingly opaque to archaeologists. Indeed, many researchers have concluded that farming in Chaco Canyon was too constrained by poor soils to have supported the dynamic developments associated with the massive stone structures and extensive trade systems of the Bonito Phase. The popular perspective that Chaco was mysterious or enigmatic is largely a response to this view of the canyon as agriculturally marginal. In this study we argue that a predictive model of potential agricultural productivity that includes other portions of the canyon besides the floodplain indicates that Chaco was not marginal for farming. The results of this analysis suggest that great house communities may have been sited to control local production zones and that some great houses may have been linked to others in order to manage multiple agricultural areas.  相似文献   
5.
X-ray fluorescence analysis of obsidian artifacts from sites located in Chaco Canyon and from three Chaco-era communities in New Mexico permits determination of their geological origin. These source data are used to describe patterning in obsidian procurement in sites located in Chaco Canyon dating from A.D. 500–1150, and in a three non-Canyon communities occupied during the period of Chaco Canyon's regional prominence (ca. A.D. 875–1150). These data demonstrate that the most proximate sources generally dominate the sourced obsidian assemblages from sites of all periods, but also suggest differences in procurement patterning both over time and across space. Within Chaco Canyon, there is a notable shift from Mount Taylor obsidian to use of Jemez Mountains sources over time. These data also suggest that earlier analyses of obsidian from sites in Chaco Canyon misidentified some obsidian artifact sources; these new data indicate the central areas of disagreement and provide a revision of procurement patterning. In the Chaco-era communities located outside Chaco Canyon, procurement patterning diverges. The Blue J community shows an increase in use of the nearby Mount Taylor source over time. Two communities located toward the southern extent of the Chaco great house distribution reveal a markedly distinct procurement pattern, obtaining nearly all of their obsidian from southern sources largely unrepresented at Chaco Canyon. Combined, these data provide new insights into raw material procurement and artifact production at sites in Chaco Canyon, and in communities occupied during the Chaco Phenomenon, the period of the Canyon's greatest regional influence.  相似文献   
6.
Archaeological cobs free of mineral contaminants should be used to source the soils in which they were grown. Mineral contaminants often contain much higher concentrations of metals than vegetal materials and can alter a cob’s apparent metal and heavy-isotope content. Cleaning a cob via immersion in an acid solution for more than a few minutes will result in the incongruent and sometimes complete leaching of metals, including strontium (Sr), from the cob. When using 87Sr/86Sr to determine the location of potential agriculture fields, it is best to either integrate several depth-integrated soil samples or to integrate several vegetation samples from individual fields. Biologically labile Sr in semi-arid Southwestern soils largely originates from eolian source or sources and usually is not derived from underlying bedrock. Existing Sr-isotope data indicate that archaeological cobs from Aztec Ruins came from either the Mesa Verde-McElmo Dome or Totah areas, that Pueblo Bonito and Chetro Ketl cobs, from Chaco Canyon that predate A.D. 1130, probably came from the Rio Chaco corridor, and that cobs from Chaco Canyon, that postdate A.D. 1130, probably came from either the Totah or Zuni areas.  相似文献   
7.
Laura Smith 《对极》2018,50(5):1396-1414
Across the fiction and non‐fiction writings of Edward Abbey (1927–1989), the anticipated restoration of Glen Canyon on the Colorado River is a recurring theme. This article employs Abbey's polemic for the removal of Glen Canyon Dam to critique contemporary debates on dam decommissioning, water politics, and ecological restoration in Glen Canyon on the Utah–Arizona border. The endeavours (and fantasies) of Abbey's fictional quartet of eco‐saboteurs reveal his radical and anarchical imaginings on how to remove the dam, yet his non‐fiction works often suggest why Glen Canyon should be restored. The politicisation of Abbey's philosophy is explored through (1) organisational, institutional responses to the question of draining Lake Powell reservoir and decommissioning the dam, and (2) how the ideology of Abbey's fictional gang is recast—and plays out—in the actions of environmental activists. This article argues that Abbey remains an important voice in the battle to restore the Glen.  相似文献   
8.
This paper is the second of the two papers, discussing the rocking and resultant component of rotations, with the torsional components of motions presented earlier in the first paper for the case of out-of-plane SH waves excitation on a semi-parabolic canyon. The rotational motions are gaining importance in recent years in the field of strong-motion seismology and earthquake engineering. Many previous papers on out-of-plane SH waves excitation presented the associated torsion rotational motions, when in fact there is also a rocking rotational component of motions. Both the rocking and torsion rotational motions, in as much as the translational motions, had shown to play an important role in structural responses, even though rotations are not incorporated into building design codes at present. Studying the rotational motions can thus help to a better understanding of the behavior of surface topographies that are in the vicinity of structures in the event of seismic excitation. This paper included, besides the additional rocking motions, also the resultant rotational motions combining torsion and rocking.  相似文献   
9.
Unusual cone‐shaped iron oxide concretions occur in the Late Triassic, lower fluvial sandstone member of the Trujillo Formation at Palo Duro Canyon in the Texas panhandle. In situ concretions are significant because they record both historical information about past processes that occurred within the geologic unit and present‐day information about the ability of the unit to conduct fluids. The dominant orientation of the concretions is cone‐apex up, body radiating down and out, with long axis perpendicular to bedding. Concretion morphologies are associated with the sedimentary texture and primary bedding structure of the host rock and the corresponding hydrologic regime (i.e. advection versus dispersion for iron‐transport behavior). Three lithofacies in the lower Trujillo member exhibit different cone forms. Field observations of cone orientation and morphology suggest vadose conditions for diagenetic precipitation of iron oxide cements, with timing potentially represented by the major pre‐Miocene unconformity.  相似文献   
10.
A multivariate statistical technique, principal-component analysis, is used to interpret pollen assemblages from archaeological context in terms of paleoenvironmental information. The pollen samples originate from an archaeological site in northeastern Arizona (Canyon del Muerto) covering the period between AD 700 and AD 1300. Through the use of principal-component analysis the percentage constraint in the pollen counts is removed and the data set effectively reduced to groups of co-varying taxa. Once these groups are ecologically defined as to the environment they represent, their changes of dominance through time can be analysed. This study has shown a correlation between a population expansion in Canyon del Muerto (AD 1050–1150) and the dominance of upland forest types suggesting slightly cooler and/or wetter conditions. The pollen data compare well with the tree-ring indices for this region. Local disturbance is reflected in the record during the period of greatest population. A shift to a shrubland vegetation during the peak construction phase indicates the clearing of cottonwood, fir, spruce and pine (all found within the site) by local inhabitants. Thus, the palynological evidence suggests both cultural and climatic factors are involved in the explanation of pollen deposition.  相似文献   
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