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J. M. PARÉS A. PÉREZ‐GONZÁLEZ J. L. ARSUAGA J. M. BERMÚDEZ DE CASTRO E. CARBONELL A. I. ORTEGA 《Archaeometry》2010,52(5):882-898
We use a combination of rock magnetism (anisotropy of magnetic susceptibility, AMS) and magnetic polarity to characterize cave deposits and as a proxy for sedimentary fabric. In three localities at the Atapuerca archaeological site (Galeria, Gran Dolina and Sala de los Cíclopes), magnetic foliation (Kmax/Kint) is always greater than lineation (Kint/Kmin), consistent with a primary, depositional, sedimentary fabric. Our results, although preliminary, reveal a higher degree of anisotropy in autochtonous deposits compared to allochthonous deposits, possibly indicative of a higher hydrodynamic regime in the former. At two localities the magnetic lineation (Kmax) defines a cluster, which is thought to be antipodal to the palaeocurrent direction. Hence we are able to retrieve palaeoflow directions in deposits that otherwise lack any other sedimentary structure. We conclude that AMS is a powerful tool for determining the hydrodynamic character of depositional environments in cave sediments at the Atapuerca archaeological site. A better understanding of the depositional environment and how sedimentation occurred allows reconstruction of the karst evolution and ultimately a better definition of human interaction with the environment. 相似文献
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This article provides a synthetic account of the historical development of London's water supply system within its wider national context, and addresses the current organizational setting of the water sector. Particular attention is paid to the post-Second World War period, which marked a transition towards integrated water management in England and Wales, a trend that has been consolidated since the 1970s. The article emphasizes the continuities and contradictions arising from the different combinations of public and private management strategies characterizing the UK water sector, and their implications for the sustainable management of water resources. It argues that there exists an in-built contradiction in the current institutional framework between the profit-oriented rationale of the private operators and the goals of efficiency, equity, and environmental sustainability pursued by the water regulators. Within this framework, it highlights the key policy issues facing the metropolitan water systems, and suggests what their most likely trajectories might be in the foreseeable future. 相似文献
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