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11.
The effect of skeletal exposure in a marine environment is an area of taphonomy that has been little investigated at the microscopic level. Understanding the peri‐mortem and subsequent post mortem history of deposition and/or redeposition is extremely important for event reconstruction and to identify deliberate or accidental redeposition. The material used for this study comes primarily from the Mary Rose shipwreck (a marine mass fatality dated AD 1545), and forensic material recovered from marine, lacustrine and terrestrial contexts is retrospectively referenced. Work presented here outlines a definitive type of marine exposure seen in temperate shallow off‐shore and intertidal marine contexts, and illustrates how it may be differentially identified from terrestrial deposition and exposure. Furthermore, the effects of rapid deposition on skeletal remains have been documented, and results indicate that marine organism fouling activity can be fully inhibited by rapid deposition of sediment. The responsible organism itself remains unidentified, but produces tunnels which are peripheral in their distribution and maintain fixed dimensions and morphology and are here associated with marine exposure. This type of microstructural change is unique and is not found in terrestrial or freshwater contexts. The study demonstrates a taphonomic microstructural change to bone and teeth which may be identified microscopically and interpreted as evidence of marine exposure. Secondarily, the history of depositional exposure between the two main Tudor layers has provided a new level of detail concerning exposure and site formation processes. The earliest Tudor layer formed rapidly over a period of months and contained no evidence of microstructural tunnelling, whereas microstructural tunnelling was seen exclusively in the second Tudor layer, formed over a period of decades, a period during which the ship's hull collapsed and a more open marine environment dominated. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
12.
In September 1870, explorer Truman C. Everts, a member of the Washburn-Doane expedition to the then little-known region of the Upper Valley of the Yellowstone River, became separated from the main party and found himself without his horse and supplies alone in the ‘wilderness’. Everts spent 37 days struggling to effect his escape from his life-threatening predicament before being rescued by a two-man search party. The news of his separation, conjecture as to his possible fate, and reports of his subsequent rescue caused a sensation both locally and nationally and consequently earned celebrity for Everts and, crucially, for the place where the calamity occurred. Drawing on Merleau-Ponty's phenomenology and non-representational work in cultural geography which explores the relation between self and world, body and landscape, this article revisits Everts' 1871 account of his ‘perilous’ misadventure to consider how his encounter with Yellowstone was embodied and, through its retelling, ultimately became inscribed on the place itself.  相似文献   
13.
The conservation in situ of underwater archaeological heritage is a highly stimulating subject for both archaeologist and conservator as it permits planning and experimentation of new treatment methods opening up new possibilities for conservation, protection and scientific research. This paper offers some remarks on this subject and shows the experience of some Italian underwater archaeological parks.  相似文献   
14.
The INTIMATE (Integration of ice-core, marine and terrestrial records) project, the successor to the North Atlantic Seaboard Programme of International Geological Correlation Programme (IGCP-253) ‘Termination of the Pleistocene’, began in 1995 with the aim of integrating proxy climate records from around the North Atlantic during the Last Termination (18–8?ka BP). The INTIMATE remit has since expanded geographically to include the entire Atlantic basin and Australasia, while an extended temporal framework now covers the early Holocene and the Last Glacial cycle. This short paper outlines the principal achievements of the INTIMATE research community, which include the development of an event stratigraphy for the North Atlantic region; the establishment of protocols for ice–land–ocean correlation; important contributions to geochronology, most notably to tephrochronology, and to palaeoenvironmental and palaeoclimatic reconstructions; and the designation of the Greenland ice-core record as the global stratotype for the Pleistocene–Holocene boundary. Future directions of the INTIMATE programme are also briefly considered.  相似文献   
15.
The simulation of Sea-ice in a coarse resolution ocean general circulation model is examined in Hudson Bay and surrounding waters. Sea-ice distribution and duration compared well to climatological values, although ice thickness is undersimulated as it is in other modelling work. In Hudson Bay ice thickness variation was dominated by the atmospheric forcing as shown by the symmetric response of ice thickness to warming and cooling scenarios. Below ice heat fluxes play a more significant role in Foxe Basin and Baffin Bay where they mitigate air-ice heat loss by as much as 40 percent, thus limiting ice thickness and duration. Below ice heat flux reduces by 23 percent for the region of study (Hudson Bay, Foxe Basin, Baffin Bay, and Labrador Sea) for a global 3°C cooling and increases by 9 percent for a 3°C global warming. This asymmetric response is attributed to the ocean's asymmetric response to warming and cooling scenarios. In so much as Hudson Bay is dominated by atmospheric forcing rather than under ice heat as these results indicate, coarse resolution models may be useful in assessing the impact of change. However the necessary reconfiguration of the model grid render results from Foxe Basin and Hudson Strait less credible. On étudie la simulation de glace marine dans un modèle de circulation océanique générale à faible résolution dans la baie d'Hudson et dans les eaux avoisinantes. La distribution et la durée de la glace marine correspondent bien aux valeurs climatologiques, bien que l'épaisseur de la glace soit sous-simulée comme c'est le cas dans d'autres travaux de modélisation. Dans la baie d'Hudson, la variation de l'epaisseur de la glace est dominée par le forçage atmosphérique, comme on peut le voir d'après la réponse symétrique de l'épaisseur de la glace suivant les scénarios de réchauffement et de refroidissement. Les flux de chaleur sous la glace jouent un rôle plus important dans le bassin de Foxe et la baie Baffin, où ils permettent une réduction des pertes de chaleur air-glace allant jusqu'à 40 pour cent, limitant ainsi l'épaisseur de la glace et la durée. Le flux de chaleur sous la glace diminue de 23 pour cent dans la région étudiée (baie d'Hudson, bassin de Foxe, baie Baffin et mer du Labrador) pour un refroidissement global de 3C et augmente de 9 pour cent pour un réchauffement global de 3C. On attribue cette réponse asymétrique à la réponse asymétrique de l'océan aux scénarios de refroidissement et de réchauffement. Dans la mesure où, comme l'indiquent ces résultats, la baie d'Hudson est dominée par le forçage atmosphérique plutôt que par la chaleur sous la glace, des modèles à faible résolution peuvent être utiles pour évaluer l'impact des changements. Cependant, la reconfiguration nécessaire de la grille du modèle atténue la crédibilité des résultats obtenus dans le Bassin de Foxe et le détroit d'Hudson.  相似文献   
16.
A quantitative bioenvironmental study of cranioskeletal size has been made of a latitude-ordered sequence of 14 series of adult skeleton sets (N=305): the archaeological remains of aboriginal maritime peoples inhabiting the west coast of North America between southern California and the Arctic. Of eight osteometric parameters of cranioskeletal size developed, the most important are partial skeleton volume (PSK) and cranial capacity (CC); and the principal bone-affecting environmental factors are the northerly climate (CLIM2c), the reconstructed diet deficient in calcium and overabundant in animal foods and vitamin D (DIET3c), and demographic stress (DSg). Prior research has demonstrated that cranioskeletal size increases with geographical latitude and decreases under dietary calcioprivation and unphysiologically high birth rates. Upon linear multifactorial statistical analysis our main finding, limited to the Amerindian subsequence (n=11 series) from the Santa Barbara Channel, the San Francisco Bay Region and the Northwest Coast, is that PSK and CC vary in direct proportion to CLIM2c, and inversely with DIET3c and DSg. Controlling for the latter two osteoantitrophic factors, coastal Amerindian female PSK rises by 9% between 34 and 54°N latitude, CC by 5%; and the male incremental rates are somewhat higher, 13 and 10%, respectively. This newly discovered climate-dependent race cline, an example of Bergmann's Rule, is interpreted as factual evidence of a mid-Wisconsin or earlier arrival date for the first Palaeoindians. Cranioskeletal size of the very small (n=3 series) Western Eskimo subsequence approximates the northernmost values of the coastal Amerindian distribution. © 1998 John Wiley & Sons, Ltd.  相似文献   
17.
In this paper I evaluate the effects of wave and tidal erosion on element‐specific measures of phenotypic variability. Previous research has found a high correlation between skeletal weight, shape, and density and the transport potential of an element exposed to hydrodynamic forces. However, no previous studies have attempted to address the issue of within‐element sorting based on selective removal of only the smallest members of a given element class. I evaluate this hypothesis using a human skeletal sample from Bird Island (8DI52) located in Dixie County, Florida. This sample comprises two components, an eroded sample that was exposed during severe storm and tidal activity, and an uneroded sample excavated from primary context. The measurement‐specific means for the subcomponents were compared using Student's t and Wilcoxon tests and variability differences were evaluated based on standard deviations, coefficients of variation, and maximum/minimum indices. The data included maxillary and mandibular tooth dimensions and postcranial metrics. No evidence for selective winnowing based on within‐element size was found in this data set. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
18.
区域海洋经济发展的结构性演进特征分析   总被引:15,自引:0,他引:15  
产业结构和空间结构问题,是经济地理学和区域经济学研究经济发展问题的核心命题。本文从区域视角,在海洋经济的实质及其区域经济特性分析的基础上,应用区域产业结构和空间结构的基本理论,揭示了区域海洋经济的结构性特征及其演进的基本规律,以期为海洋经济发展战略与规划的制定提供依据。  相似文献   
19.
早期楚文化探索   总被引:1,自引:0,他引:1  
本从献梳理开始,首先对早期楚化的时限作了限定,认为早期楚化应限于西周时期,不应无限地上溯。同时认为商代确实已有楚,但两周之楚不同于商代之楚,是周王朝分封之楚。在献记载的楚人活动地域内,对西周时期的诸考古学化遗存进行了分析。认为只有鄂西北区(包括陕东南和豫西南)楚化出现最早,而且分布普遍;荆州区、西陵峡区和沮漳河流域楚化出现的时间不完全一样,这些地区楚化的出现是楚人不断扩张的结果。  相似文献   
20.
Abstract

Rescue excavations carried out during the 1970s at the Iron Age hillfort of Broxmouth in East Lothian produced a small assemblage of fish bone. Despite some uncertainties surrounding the recovery of this material, recent analysis has produced highly unusual results. In particular, the presence of large specimens of ling and other species raises the possibility that the Broxmouth community was, at least periodically, engaged in deep-sea fishing. This suggestion is at variance with present understandings of Iron Age fishing strategies which generally envisage more expedient practices, such as line fishing from the shore. Indeed, it has even been suggested that the consumption of fish was avoided altogether in Iron Age Britain, for religious or cosmological reasons. The composition of the Broxmouth assemblage thus has potentially important implications for our understanding of Iron Age marine exploitation.  相似文献   
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