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121.
Here I report on the decay processes of microscopic organic residues left on stone tool surfaces after their use. Residue analysis on ancient stone tools facilitates reconstruction of past activities. This study enables predictions about the circumstances under which ancient residues preserve. Experimental tool sets with modern residues were buried for a year in separate deposits at Sterkfontein, Sibudu (South Africa) and Zelhem (the Netherlands) whose pH and geomorphology varied, they were then analysed using light microscopy. Biological weathering mainly causes residue decay. In unstable environments rich in microbes and micro-organisms, residues decay quickly. From an archaeological perspective this means that sites that are stable, desiccated, waterlogged, extremely acidic or alkaline and extremely cold or hot sites. Different residue types have different preservation optima and this may lead to a preservation and perhaps interpretation bias. The preliminary predictive models presented in this paper could aid in the considered selection of sites and samples.  相似文献   
122.
Scientists from the National Institute of Standards and Technology (NIST) worked in a collaborative partnership with archaeologists from the National Park Service's (NPS) Submerged Resources Center (SRC) to develop a finite element model (FEM) of the battleship USS Arizona. An FEM is a computer-based engineering model that calculates theoretical stresses, propagation of force, and shape changes to a structure under loads using thousands or even millions of individual elements whose individual responses are well understood. NIST researchers created an FEM of an 80 ft. (25 m) midships section of the Arizona site to analyze archaeological site formation processes on the sunken battleship, in particular to determine the current condition of the wreck and predict its future strength and structural integrity as it continues to corrode. The NIST's FEM study is one aspect of a larger project under the direction of the NPS, the USS Arizona Preservation Project, whose goal is to determine the nature and rate of corrosion affecting USS Arizona, and to model its long-term structural deterioration. The FEM incorporates findings from other key components of the USS Arizona Preservation Project, such as steel hull corrosion rates, structural surveys of the vessel, sediment compaction studies, and analysis of the concretion that covers the ship's hull, into a single tool that is being used to predict how the wreck will degrade in the future.  相似文献   
123.
Despite its worldwide use as a stone tool raw material, quartz is known to be a difficult material for archaeologists. The main reason for this is the tendency of quartz flakes to fragment during detachment, which complicates the use of traditional lithic analyses. In this article we present an experimental study of quartz flake fragmentation. We evaluate the method called fracture analysis that has been developed and used explicitly for the study of quartz assemblages. The method assumes high predictability of quartz flake fragmentation, but our experiments show that there is significant variation in fragmentation that fracture analysis does not take into account. Our results indicate that this variation is partly explained by indenter hardness, the relative thickness of the detached flake, as well as individual knapper-related factors. These results undermine the applicability of quartz fracture analysis in its current form. In addition, we discuss the effects of flake fragmentation on the technological organisation of prehistoric quartz users and suggest that it has affected reduction strategies as well as blank and tool dimensions. We also suggest that there should be mobility-related differences in archaeological assemblages in terms of the quality of the quartz raw material and that the curation of quartz should be low in relation to better quality raw materials used parallel with it.  相似文献   
124.
This paper presents results of use-wear study on lithic artifacts from two Later Stone Age sites (Gelalo and Misse) on the Red Sea Coast of Eritrea. The sites produced large quantities of lithic artifacts in association with mollusk shells and ostrich eggshell beads, but it is unclear if all the stone tools were required for bead and mollusk shell processing. The study involved recording of microfracture damage traces in order to infer the use-material and the manner in which the artifacts were used. A large percentage of the analyzed samples from Gelalo and Misse preserve wear patterns suggestive of human use. The diagnostic wear types include: (1) dense step, snap (crushing) and hinge fractures typically confined on the working edges, and (2) feather scars organized in a scalar manner visible on the ventral and dorsal surfaces of the active parts. The observed damage patterns suggest cutting and engraving medium to hard materials. The evidence is incomplete for more generalization about the specific activities carried out at the sites. A brief experimental study involving ostrich eggshell drilling, oak twig sawing and bark scraping, meat slicing, and mollusk shell sawing and drilling was carried out to aid interpretation of wear features observed on the archaeological specimens. Wear traces produced by sawing mollusk shell and oak wood showed close affinity to those observed on the archaeological specimens. The study contributes important information about early Holocene site use on the Red Sea Coast of Eritrea. The close association of used lithic artifacts, symbolic objects (beads) and broken shell remains indicates that the sites were habitation areas.  相似文献   
125.
Despite an increasing number of publications regarding the Pre-Columbian earthworks of the Llanos de Moxos, there have been no serious attempts to undertake a systematic survey of the archaeological remains of this lowland region in the Bolivian Amazon. Based on the GIS analysis of data gathered in the field and retrieved from satellite images, we discuss the spatial distribution of the Pre-Columbian settlements in a 4500 Km2 area of the Llanos de Moxos to the east of Trinidad, capital of the Beni Department, and their relationship with the geographical settings. Our findings shed new light on the prehistory of the region and bear important implications for our understanding of the impact of Pre-Columbian human occupation.  相似文献   
126.
In Western and Central Europe, many woods are clearly separated from the surrounding countryside by permanent physical boundaries. While such boundaries are now out of use, in the past they were widespread and important landscape features. This paper argues that many woodland boundaries originate from the Middle Ages and perhaps even more from the Early Modern Period. Their existence was connected to a specific form of woodland management (coppicing) but also to ownership structures and through these to grazing regimes. With their various forms, permanent woodland boundaries served to separate woodland from the surrounding countryside both in a legal and physical sense. There are four basic types of permanent woodland boundaries: woodbanks, walls, stone rows and lynchets, all of which can still be studied in the landscape today. Because of their varied state of preservation and also because of the difficulties in creating relative chronologies, dating woodland boundaries is a very challenging task. However, even a basic typology can provide valuable information for a number of scientific disciplines, including landscape history, historical geography, archaeology and ecology. Permanent woodland boundaries are a part of European cultural heritage. They should be recognised and protected similarly to all other ancient landscape features.  相似文献   
127.
A central but often unasked question in political and sociological scholarship concerns the conditions that precipitate cooperation on large-scale transnational energy projects, especially among “developing” and “emerging” economies. Using the example of two multi-billion dollar pipeline systems – the Trans-ASEAN Natural Gas Pipeline (TAGP) Network in Southeast Asia and Baku-Tbilisi-Ceyhan (BTC) Pipeline in the Caspian Sea – this article explores the factors that result in successfully completed projects, and those that lead to conflict and contention. After drawing from extensive research interviews and field research, the article approaches politics and technology through the lens of science and technology studies. It relies on the interdisciplinary concepts of “relevant social group” and “technological frame” to identify coalitions of actors associated with each pipeline project. The paper then investigates the interests and motivations behind these groups to illuminate the challenges facing the TAGP and those that accelerated the completion of the BTC. The paper concludes by offering some thoughts on the diverse elements needed to incentivise cross-border energy infrastructure, and what these may mean for energy and public policy scholars.  相似文献   
128.
129.
The 'Mardi Gras' Shipwreck is the remains of an early-19th-century sailing vessel lost in approximately 1220 m of water in the Gulf of Mexico. A recent archaeological investigation documented the wreck and recovered several artefacts, including glassware, ceramics, navigational instruments, a cannon, and a stove. Analyses of these artefacts and the surviving hull have led to preliminary conclusions on the nature of the vessel and its crew.
© 2009 The Authors  相似文献   
130.
The macroevolutionary approach in archaeology represents the most recent example in a long tradition of applying principles of biological evolution to the study of culture change. Archaeologists working within this paradigm see macroevolutionary theory as an effective response to the shortcomings of neo-Darwinian biological evolution for studying cultural evolution. Rather than operating at the level of individual traits, macroevolutionary archaeologists emphasize the role of hierarchical processes in culture change. While neo-Darwinian archaeologists disavow any element of human intent in culture change, to macroevolutionary archaeologists human agency is a key component of cultural evolution that allows cultures to respond to pressures more quickly and with greater degree of flexibility and directedness than found in biological evolution. Major culture change, when it happens, is likely to be rapid, even revolutionary, with periods of rapid change separated by periods of relative stasis of actively maintained stability. The emergence of Neolithic cultures has long been recognized as one of two periods of major revolutionary culture change in human prehistory. Here I examine the record for the Near East, tracing the empirical record for the origin of agriculture in this region, as well as other demographic, social, and ideological components of Neolithic emergence. While the empirical record from the Near East subscribes in a general way to basic principles of macroevolutionary theory, cultural evolution cannot be understood through appeal to principles of biological evolution alone, whether based in macroevolutionary theory or neo-Darwinianism. Instead, the key role of human agency in culture change distinguishes cultural evolution from biological evolution and requires a more pluralistic and less doctrinaire appeal to multiple models of change based in both the biological and social sciences.  相似文献   
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