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101.
In the field of maritime archaeology, the use of maritime, coastal, riverine, and lacustrine spaces by past societies has been perceived in different and changing viewpoints. These perspectives have flourished in dynamic and varying ways in many countries, and under different theoretical constructs. If in the 1970s the subject was perhaps not recognized as a central research subject by much of our community, it is now not only accepted but it has become a robust area of interest in maritime research. Two concepts in Latin America have been accepted that have had widespread application and influence, namely the regional maritime context and the maritorio. The points of contact between both are so intense that it is possible to speak about a single alternative with two possible names. In this article, their origins, applications, and theoretical influences are presented in a way that unifies these two concepts into a single approach (the maritorium), and examines how these ideas have been applied to research carried out in Mexico, Chile, and Uruguay. These applications are wide ranging, as they include the interconnected complexity between land and sea as used and inhabited by past societies. They have been applied in the study of ship traps, whole fleets, sites of maritime conflict and warfare, exploration activities, and ethnographic research. These will also be presented in light of other concepts of similar interest in the international sphere, such as the widespread concept of the Maritime Cultural Landscape, and also in view of other theoretical frameworks coming from the wider sphere of the profession, such as Landscape Archaeology and Phenomenological Archaeology.  相似文献   
102.
This study shows the results of a multidisciplinary collaboration between the University of Calabria (Italy) and the National Autonomous University of Mexico (UNAM), about the compositional characterization of some mortars taken from Hagia Sophia in Istanbul (Turkey), one of the most important buildings in antiquity. Twenty samples of joint mortars were analysed by micro-chemical analyses (SEM-EDS), X-ray powder diffraction (XRPD), optical microscopy (OM) and transmission electron microscopy (TEM). The compositional study allowed us to define, with more detail, the construction phases of the fifth, sixth and tenth century. The petrographic analysis in thin section by optical microscopy showed four typologies of sands, used as aggregate, with specific compositional features. SEM-EDS analyses and TEM observations of the binder around the ceramic fragments of the aggregate showed the presence of different morphologies of single C-S-H compounds.  相似文献   
103.
Certain aspects of the formation processes of simple, flat archaeological combustion structures such as those present in the Middle Palaeolithic record remain unexplained. Such kind of combustion structures are commonly affected by postdepositional agents and often, their only distinct, well preserved component is a thin black lens on the ground. Hence, understanding the nature of this black lens is essential towards archaeological interpretation. From an interdisciplinary microstratigraphic approach, we present a case study in which for an entire experimental series of flat combustion structures the black layer represents the fire-altered topsoil on which the fire was made. Parallel analysis of archaeological Middle Palaeolithic combustion structures from the site of El Salt (Alicante, Spain) reveal similar patterns, leading to significant implications for archaeological interpretation. In the light of these results, special attention must be paid to the formation processes of flat Middle Palaeolithic combustion features, as black layers and the material contained in them are not necessarily linked with combustion but with preceding activities or events. In such cases, black layers represent intact remnants of occupation surfaces, concealing significant behavioural and palaeoenvironmental information relevant to the reconstruction of Middle Palaeolithic societies.  相似文献   
104.
Konservat-Lagerstätten are a source of insurmountable information on the diversity of fossil assemblages during the lower Palaeozoic. Soft-bodied fossils are especially rare in South America, but a new locality has been discovered from the Middle Ordovician of Peru that has produced the fairly well-preserved possible palaeoscolecidan Juninscolex ingemmetianum gen. et sp. nov. The distinctive characteristics of this worm make it similar to European taxa within the group.  相似文献   
105.
106.
Archaeosediments are deposits with a direct or indirect anthropogenic component. They provide useful information about past human activities and interaction with the environment. When other materials, such as pottery, are present in archaeosediment layers, the combination of TL ages from pottery and OSL ages from sediments can provide complete data about the occupation and evolution of an archaeological setting. In Mesopotamia, tells are mounds formed by the debris of human occupation and the accumulation of muddy sediments mainly due to the decomposition of mud bricks in ancient towns. Many other materials such as pottery fragments, bones and charcoal can be found in the sediment layers. The combination of OSL, TL and radiocarbon ages can be very useful in the case of the Bronze Age Period in Syria, allowing the occupation sequence of such archaeological sites to be reconstructed. Tell Qubr Abu al-’Atiq, is located on the left bank of the Middle Euphrates River (Syria). The archaeological artefacts found in the sediment layers (pottery) collected during excavations in two areas of the site, indicated the occupation of the tell during the Early and Late Bronze Age by typological pottery classification. The radiocarbon ages of charcoal indicate that human occupation fits the archaeological hypothesis, providing an older and maximum occupation period between 2800 and 2300 BC and a younger period between 1400 and 900 BC. OSL dating of sediments shows ages younger than charcoal, while TL ages of pottery are generally older than sediment and charcoal ages. This can be explained as the different materials correspond to different events. The charcoal and pottery correspond to occupation periods, while sediments correspond to the further destruction of the site.  相似文献   
107.
108.
This article presents results of a statistical study focused on evaluating inelastic displacement ratios (i.e., ratio of maximum inelastic displacement with respect to maximum elastic displacement demand) of degrading and non degrading single-degree-of-freedom (SDOF) systems subjected to forward-directivity near-fault ground motions. CR spectra are computed for normalized periods of vibration with respect to the predominant period of the ground motion to provide a better ground motion characterization. This period normalization allows reducing the record-to-record variability in the estimation of CR. An equation to obtain estimates of CR for the seismic assessment of structures exposed to forward-directivity near-fault ground motions is proposed.  相似文献   
109.
Moseley’s (1975) Maritime Foundations of Andean Civilization hypothesis challenges, in one of humanity’s few pristine hearths of civilization, the axiom that agriculture is necessary for the rise of complex societies. We revisit that hypothesis by setting new findings from La Yerba II (7571–6674 Cal bp) and III (6485–5893 Cal bp), Río Ica estuary, alongside the wider archaeological record for the end of the Middle Preceramic Period on the Peruvian coast. The La Yerba record evinces increasing population, sedentism, and “Broad Spectrum Revolution” features, including early horticulture of Phaseolus and Canavalia beans. Yet unlike further north, these changes failed to presage the florescence of monumental civilization during the subsequent Late Preceramic Period. Instead, the south coast saw a profound “archaeological silence.” These contrasting trajectories had little to do with any relative differences in marine resources, but rather to restrictions on the terrestrial resources that determined a society’s capacity to intensify exploitation of those marine resources. We explain this apparent miscarriage of the Maritime Foundations of Andean Civilization (MFAC) hypothesis on the south coast of Peru by proposing more explicit links than hitherto, between the detailed technological aspects of marine exploitation using plant fibers to make fishing nets and the emergence of social complexity on the coast of Peru. Rather than because of any significant advantages in quality, it was the potential for increased quantities of production, inherent in the shift from gathered wild Asclepias bast fibers to cultivated cotton, that inadvertently precipitated revolutionary social change. Thereby refined, the MFAC hypothesis duly emerges more persuasive than ever.  相似文献   
110.
Desalination of rocks used in monuments is a common strategy to reduce the possibility of deterioration by soluble salt crystallization processes. In the last years, some laboratory studies have demonstrated that the application of electrokinetic techniques allow to achieve higher desalination effectiveness, overcoming most limitations of the traditional methods. However, to our knowledge no studies have been conducted on the effectiveness of this technique for in situ desalination of granite. The present study is aimed at filling this gap. The results of an in situ desalination intervention using electrokinetic methods, on a column highly contaminated with salts are presented. The desalination method was optimized to desalinate large in situ structures, trying to establish the necessary protocols (buffering system, irrigation system, setup, etc.) to obtain results as satisfactory as those obtained in laboratory. The results demonstrated the high effectiveness of this method in terms of total salt extraction and depth of salt extraction. The concentration of anions in the column was decreased by more than 80% after 55 days of treatment. No mineralogical and aesthetic damages on the stone were detected after the treatment, confirming the reliability of this method to be applied in situ on granitic rocks.  相似文献   
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