Combined application of pansharpening and enhancement methods to improve archaeological cropmark visibility and identification in QuickBird imagery: two case studies from Apulia,Southern Italy

Launch of Very High Resolution (VHR) satellite sensors meant a significant evolution for Remote Sensing archaeological applications since data with high spatial resolution may be used to identify signals related to buried archaeological remains (e.g. cropmarks, soilmarks, dampmarks) in very extended territories. The aim of this work is to develop a suitable image processing workflow to improve the cropmark visibility in the VHR satellite images. The workflow implemented consists of two steps: first the panchromatic and multispectral images have been pansharpened in order to merge the two images, then some Enhancement methods have been applied on the pansharpened image. As a result of the several tested pansharpening techniques, the Principal Component Resolution Merge yields images of very good quality useful not only for visualization but also as input for further processing. Among the different enhancement methods taken into consideration, the Spatial Enhancement, carried out by applying the Wallis Adaptive filter further improve the visibility and recognition of the archaeological signals.     

Policy Punctuations and Issue Diversity on the European Council Agenda

The European Council is the highest political body of the European Union and the main venue for setting the agenda on high politics. Using a new dataset of all content‐coded European Council Conclusions issued between 1975 and 2010, we analyze the policy agenda of the European Council and test hypotheses on agenda change and diversity over time. We find that the theory of punctuated equilibrium applies to the agenda of the European Council, which exhibits a degree of kurtosis similar to that found in policy agendas of other institutions located at the juncture between input and output of the policy process. Throughout the 36‐year period, agenda‐setting dynamics involved both small changes and major shifts but also more frequent medium‐sized negative changes than found elsewhere. Given capacity limits to the agenda, large expansions of attention to topics involved large cuts in attention. Cuts were more often medium in size in order to maintain some level of attention to the topics affected, even though issue disappearance from the European Council agenda has been frequent too. This relates to the functions of the European Council as venue for high politics, with expectations about issue attendance rising with increasing policy jurisdictions throughout the European integration process. Studying dynamics over time, we measured entropy to show how the agenda became more diverse but also displayed episodic concentration in an oscillating pattern. This can be accounted for by the nature of the European Council as a policy venue: increasing complexity of this institution pushed the members to produce a more diverse agenda, but capacity limits and the need to be responsive to incoming information led to concentration at specific time‐points.     

Permian bivalve molluscs from the Gai-As Formation,northern Namibia: systematics,taphonomy and biostratigraphy

Fossil bivalves from two horizons in the Gai-As Formation of NW Namibia are tentatively correlated with mid-Permian taxa of the Passa Dois Group of Brazil, supporting the concept that the Paraná Basin extended into Africa. The Namibian fauna includes a new genus and species, Huabiella compressa, which was previously confused with Brazilian taxa. The taphonomy of the bivalve-rich strata indicates deposition under the influence of episodic events, such as storms. The Gai-As Formation directly overlies the mesosaurid-bearing deposits of the Huab Formation, indicating a significant unconformity when compared with the more complete succession of the Passa Dois Group, Paraná Basin, Brazil. The studied bivalve assemblages are no younger than 265±2.5 Ma (mid-Permian), based on U/Pb radiometric dating of zircons from tuffs.     

Let no space go to waste: comparing the uses of space between two Late Classic centers in the El Paraíso valley,Copan, Honduras

Phosphorus analysis of earthen and plaster floors has been used in Mesoamerica to locate and identify activities at ancient sites. This study uses phosphorus analysis to discern if the inhabitants of two Late Classic coeval and proximal sites located in the El Paraíso Valley of Honduras were different culturally from each other. The buried earthen and plaster surfaces of both sites were systematically sampled and analyzed for phosphorus remains. The patterns of elevated phosphorus from these open spaces were subsequently compared to determine if differences in the habitual use and treatment of open spaces could be discerned. These differences are evaluated as a function of behavioral norms, functional responses, and cultural dispositions in order to evaluate the extent to which these two populations were indeed different from each other.     

Susceptibility measurements,optical and X-ray analysis to explain the origin of archaeological magnetic anomalies in Tavoliere lowland (Southern Italy)

Since 2002 a non-invasive investigation integrating aerial photography and high-resolution magnetometry has been carried out for reconstructing extensive ancient settlements in Tavoliere lowland (Southern Italy). Relevant magnetic anomalies were detected in all the surveyed sites allowing a precise mapping of the buried structures over more than 150 ha. Next to this research susceptibility measurements, PXRD, XRF and optical analysis were also performed in order to explain the origin of the notable magnetization contrast between the anthropogenic structures and the embedding materials, generating the measured signals. This last study was accomplished, in 2006, in Monte S. Vincenzo site, a vast Neolithic village where the remotely sensed data were also used to guide some direct inspection. Trial archaeological excavations brought to light parts of C-shaped compounds, providing complete information on the geometry and location of the sources of magnetic signals. Profiting by the archaeological feedback, the susceptibility contrast between the soil filling the ditches and the calcareous substratum was assessed in situ. A synthetic model based on this information was created and compared with the experimental data. The infilling material was also sampled for laboratory analysis: the presence of several magnetic minerals (pyroxenes, monometric magnetite, haematite) was ascertained. Furthermore optical analyses showed different types of volcanic and igneous products such as pumices, melanite garnets and lava fragments. Geomorphological and archaeometric evidence allowed us to relate these materials to activity of the Mt. Vesuvius volcano. Eventually their possible spatial distribution was inferred from recent studies on ash transportation and deposition during explosive activity.