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Methodological advancements in geoarchaeology and spatial and chronological modeling are opening new avenues to interpreting large coastal shell-bearing sites. We document the developmental histories of two such sites around Prince Rupert Harbour, Canada, using systematic percussion coring, intensive radiocarbon dating, and 3D surface mapping with Total Station and LiDAR. We also re-analyze a third site (Boardwalk/GbTo-31) excavated and radiocarbon dated in the 1960s, 1970s, and early 2000s using archival field notes, site maps, and stratigraphic profiles georectified using LiDAR. We map the natural landform beneath the sites and document the degree to which people physically modified landforms through the deposition of massive shell accumulations. We model site development through time and space and use accumulation rates and OxCal modeling to test for intentional deposition events. All three sites demonstrate complex and heterogeneous occupation histories. At each we identify instances of very rapid deposition that effectively terraced and extended parts of the natural landform to create places for constructing houses, though these episodes take place within longer histories of slower quotidian deposition. The anthropogenic modifications to the coastline in this area are the result of these mixed processes associated with long histories of occupation.  相似文献   
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Following earlier examples of mapping the subsurface of shell bearing sites using augering, we employ percussion coring to identify early Holocene shell midden components at two types of sites on the Northwest Coast of North America. We describe a method for mapping subsurface components at shell bearing sites including basal deposits, paleosols and transitions between distinct cultural components. Our research was undertaken for the purpose of identifying early Holocene shell middens above the modern shore, and as components below large shell midden villages. Our results augment the developmental trajectory of shell middens on the Northwest Coast by suggesting that pre-5000 BP forms of these sites may be more common than previously thought. In light of these results, we argue that the Northwest Coast cultural historical sequence, which locates an increase in the number and rate of accumulation of shell middens beginning 5000 years ago, to be premature. However, there are insufficient data from shell middens in the early Holocene, a sampling problem that the percussion coring methods described here can address.  相似文献   
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Established techniques that have been successfully used to characterize pore systems in conventional reservoir rocks lack the resolution and scalability required to adequately characterize the nano‐ to micrometer scale pore systems found in shale and cannot be applied on stressed samples. We have therefore investigated the utility of Klinkenberg gas slippage measurements for shale pore structure characterization. In contrast to other approaches, slippage measurements characterize the effective porosity of core samples and can be applied at stress conditions experienced in the reservoir during production. Slippage measurements on horizontally and vertically oriented samples from the Eagle Ford Shale Formation, Texas, USA, at a range of stress states revealed two orders of magnitude in slippage variation over five orders of magnitude permeability range. Slippage measurements are negatively correlated with permeability and follow similar trends to those found in other studies on higher permeability rocks. The samples had varying degrees of slippage anisotropy, which allowed interpretation of the relative contribution of tortuosity and pore size to permeability anisotropy. Slippage and therefore average effective pore size was found to vary up to one order of magnitude at a given permeability, warranting investigation of the significance this might have on flow properties and ultimately hydrocarbon production from shale.  相似文献   
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ABSTRACT In common with Aboriginal groups around Australia, the indigenous people, or Nyungars, of Perth adopt a holistic attitude towards groundwater resources. Of cultural significance are lakes, springs, soaks and watercourses that feature in Dreamtime creation narratives. Perth is experiencing major water shortages and many Nyungars feel that the degradation of the freshwater supply is a result of mismanagement and unsustainable development by non‐Aboriginal people. Proposals for dealing with the issue are seen as equally out of balance with the natural order of things. Water regulators have much to learn from indigenous Australians about water and environmental management. Although water continues to be central to Nyungar identity, the study on which this article is based found evidence of attenuated knowledge about the Dreaming, with discontinuities evident in the way significance is increasingly being read in everyplace rather than in specific ‘story places’.  相似文献   
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Between 2004 and 2011 Graham Hill and Dave Edwards plotted nearly eight thousand prehistoric artefacts from ploughed fields across the Clodgy Moor area of West Penwith. In 2011 a project was carried out by the Historic Environment Service Projects team, Cornwall Council, the Portable Antiquities Scheme and the Cornwall Archaeological Society to catalogue and digitize all the finds recorded from the fieldwalking.

The project demonstrated that some places within the project area were persistent locales which were occupied throughout the Mesolithic and Neolithic periods. The results were particularly significant because they shed light on the context of the production of greenstone axes, widely exchanged around Britain and across the Irish Sea during the Neolithic, and suggest why, despite large numbers of artefacts, no greenstone ‘axe factory’ site has been found close to the potential sources of the greenstone before.  相似文献   
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We present and test a predictive archaeological survey model that targets early Holocene paleoshorelines in the Prince Rupert Harbour area using LiDAR bare earth digital terrain models and a 15,000-year reconstructed history of relative sea level change. Despite a century of archaeological research in the study area, no sites dating earlier than 6000 cal b.p. had been identified prior to our research. Our field survey identified three early Holocene sites associated with paleoshorelines 7–10?m above current sea level (masl). These locations demonstrate repeated use through the Holocene even as shoreline position changes. We discuss these new data in relation to the early Holocene archaeological record from the rest of the northern Northwest Coast and suggest that the region was ubiquitously occupied by this time and that the lack of recorded early Holocene sites in some areas is likely a result of survey and preservation bias, rather than historical reality.  相似文献   
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Multi‐criteria evaluation (MCE) methods are useful tools to evaluate the land suitability for various uses and assist in the effective management of available land. Many common GIS‐based MCE methods, such as analytical hierarchy process (AHP), ordered weighted averaging (OWA), and a combination of AHP and OWA methods (AHP–OWA) are not able to fully represent all the logic that constitute a wide range of human decision‐making reasoning. Consequently, improved GIS‐based MCE methods such as Logic Scoring of Preference (LSP) method are needed. The main objectives of this study are to: (1) implement the GIS‐based LSP method for land suitability evaluation and (2) compare qualitatively and quantitatively the suitability maps generated by LSP and three GIS‐based MCE methods. This study was implemented with data sets from Boulder County, Colorado, USA for the case study of the urban land suitability evaluation. The qualitative properties of MCE methods and the Receiver Operating Characteristic (ROC) statistics were used as comparison metrics. The results indicate that soft computing methods and particularly LSP performed the best among GIS‐based MCE methods for the urban land use application.  相似文献   
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