Suchergebnisse

Volcanic rocks have been found to be potentially alkali-reactive in a number of countries, including Japan, New Zealand, Iceland and Turkey. In order to characterize the potential reactivity of the volcanic rocks in Azores a project is being carried out, under the support of the Azores Government: the ReAVA Project—"Characterization of Potential Reactivity of the Volcanic Aggregates from the Azores Archipelago: Implications on the Durability of Concrete Structures". This project comprises mainly: (1) petrographic assessment of the aggregates, (2) assessment of their performance in expansion tests and (3) site inspection of existing large concrete structures. This study has also the support of the IMPROVE Project—"Improvement of Performance of Aggregates in the Inhibition of Alkali-Aggregate Reactions in Concrete", aiming to minimize the occurrence of alkali aggregate reaction (AAR) in Portugal. The Azorean rocks used as aggregates are mainly basalts and some trachytes. The reactivity of this kind of rocks is usually associated with the presence of volcanic glass, altered minerals and SiO2 content of the rock. The petrographic examinations of the rocks confirmed that one of the basaltic samples contains volcanic glass. The occurrence of microcrystalline quartz as a secondary product filling the interstices of the trachyte sample was confirmed by scanning electron microscope. The results of the concrete expansion test RILEM AAR-3 showed an increasing expansion starting on 140 days and continued to grow after 2 years of laboratory testing, but below the limit of 0.05 % recommended for this method. ; 51-54pp ; The analyses by SEM/EDS were performed at CEMUP which equipment was funded by the projects REEQ/1062/CTM/2005 and REDE/1512/RME/2005 of Portuguese Foundation for Science and Technology (FCT). The authors also acknowledge the financial support of the FRC under the project M5.2.2/I/05/2011 and FCT under the project PTDC/ECM/15486/2009. ; 5 ; DM/NMM ; Urban Geology, Sustainable Planning and Landscape Exploitation

Alkali–aggregate reactions have been known for decades although the acceptance of their occurrence has been delayed in some countries until the 1990s. Potential reactivity has been identified in most of the rock types used as aggregates around the world. The most common reactive rocks are sedimentary (e.g. opaline sandstone) and metamorphic (e.g. gneiss). However, igneous rocks such as granites have also proved to be reactive in some areas and innocuous in many other regions. It has been concluded that the designation is not enough to label a rock as reactive and that microstructure is very often the determinant factor of reactivity. In the present study a summary ismade on the state-of-the-art on alkali– aggregate reactions. Emphasis is given on the identification of potentially reactive aggregates based on petrographic methods. Examples from a large number of samples analysed in the scope of a research project are presented. ; The authors would like to acknowledge Centro de Geologia (University of Porto), Fundac¸a˜o para a Cieˆncia e Tecnologia for the financial support of the Project IMPROVE (Ref: PTDC/ECM/115486/2009), and Azorean Regional Government for financial support of Project ReAVA. The SEM-EDX data were obtained at the Materials Centre of the University of Porto (CEMUP) whose equipment was funded by the projects REEQ/1062/CTM/2005 and REDE/1512/RME/2005 of FCT. ; 3 ; 1 ; 10p ; DM/NMM ; Proceedings of the ICE - Construction Materials

A key goal in the study of ancient artifacts is determining their provenance. Such information can provide insight into the production and consumption of artifacts, but may also inform discussions about local political economies. This study uses optical petrography to evaluate the tempers in ceramic samples and raw clays from Angamuco, located in the Lake Pátzcuaro Basin, Michoacán. Angamuco was occupied before and throughout the development of the Purépecha Empire (1350–1530 CE) and is thus an important case study for understanding the impacts of political change on urban landscapes and ceramic production and manufacture. We identify seven ceramic temper groups and four clay groups. The ceramic samples almost exclusively match local clays. Angamuco appears to have been relatively self-sufficient in pottery production throughout the occupation sequence. While we did identify some temporal and spatial variation in ceramic production and consumption, pottery technologies and techniques of manufacture appear to have remained relatively stable over long periods of time. Our data point to multiple small-scale producers, who focused on local clays and tempers, generating numerous, complex paste recipes. The results of this analysis contribute to our understanding of ceramic production processes at Angamuco and may be compared to provenance studies in Western Mexico and elsewhere.

This paper presents the results of an archaeometric analysis of pre-Roman and Roman ceramics from the Vaccean Iron Age hillfort of Pintia (Valladolid, Spain). The study assesses degrees of romanization and hybridization by investigating changes in local ceramic production and the dissemination of new technologies with the arrival of Roman rule. Thin-section petrography, XRD, and geochemical analyses (using XRF) have been utilised on a selection of pre- and post-conquest vessels from habitation contexts. This work goes beyond traditional typological analyses to shed light on the resilience of 'Second Iron Age' communities, who's ceramic traditions largely persist into Roman times, albeit with some changes, like shifts in the preferences and location of raw materials. ; Spanish Government FPU15/00897 ; Centro de Estudios Vacceos Federico Wattenberg (CEVFW) of the University of Valladolid ; Universidad de Granada/CBUA University of Granada

Interconnections between Egypt and the Levant have been a focus of research for many years. However, only more recently has the scientific method of thin section petrography of ceramic vessels been applied. Through petrography, the raw materials can be identified and related to their known origins, suggesting a provenance. Recent examination of jars dating from the Old kingdom, Middle Kingdom and Second Intermediate Period, New Kingdom, Late Period, and Late roman Period revealed that a number of areas in the Eastern Mediterranean were trade partners at one time or another. On the other hand, Lebanon was a long standing trade partner, undoubtedly due to the significance of the commodities exported from this region to Egypt. Thus, while the political situation in the Levant and Egypt changed dramatically across almost 3000 years, the desire to have Lebanese goods did not.

In archaeology, the analysis of ordinary things does not often lead to assessments of power. Political systems are difficult to trace materially because today they seem separate from our lives, but yet are involved in most everything we do. In this case study of first millennium BCE Idalion, Cyprus, I have found that the producers of undecorated, or utilitarian, pottery are impacted by political behavior and social relationships, which both impact their economic stability. When discussing the political economy, archaeologists describe elites as the controllers of wealth including the consumption and sometimes production of high value goods. However, I argue that they also play a role in the production of utilitarian pottery. I combine craft production theory, archaeological theories of power, and petrographic analysis, to analyze the organization of production of pottery and its role in the political economy. In the Mediterranean, and specifically on Cyprus, political economies are defined most-often through the translation of inscriptions and texts. For the first millennium BCE, the term "city-kingdom" is common on Cyprus. This use of texts and inscriptions causes a problem because archaeologists do not often assess the legitimacy of these political terms, such as kingdoms and states, through material culture, thereby allowing political types to be poorly understood. To better define the Cypriot political type, city-kingdom, I approach politics from the mode of defining power and based my analysis on the multi-dimensional nature of power. The way power impacted producers of utilitarian pottery at Idalion includes political and economic power that placed limits on their access to raw materials, trade routes, and/or markets, and also social power through the relationships potters navigated to ensure their own economic stability and success. At Idalion, power was flexible and impacted by various cultural factors and by analyzing it through pottery production I am able to provide a tentative definition of a city-kingdom.

The Opera Punta Rossa fortification was built at the end of XIX century (1887) on the South of Caprera island (North Sardinia), when returned to thinking of La Maddalena archipelago as a strategic military centre, no longer determining in relation to the only French border, but to the much larger chessboard of the Western Mediterranean. It is of singular interest not only for the functional parameters but, above all, for its imposing appearance with wide dimensions, and other many interesting technical-architectural aspects: laying modes of wall structural elements (i.e., for access portals, intrados of vaults, moldings, architraves, jambs, thresholds, cantons), use and working technics of the granite stone expertly molded for the thick masonry, characterized by the presence of loopholes and continuous modulation of materials with moldings and worked stone ashlars to highlight the wall surface. The geomaterials used are local rocks outcropping in the area of Opera Punta Rossa, belonging to the Paleozoic granitic pluton of Gallura and to the associated filonean bodies (Upper Permian - Carboniferous, between about 320 and 270 million years ago). In the fortification have been mainly used the "granite" rocks (substantially biotitic granites and granodiorites) and subordinately also the filonean rocks (especially for irregular ashlars) with variable colours and dacitic-rhyodacitic composition. Generally, the cornices and the openings were made with the lighter greyish granite facies. The stone elements were laid in place using lime or hydraulic / pozzolanic based mortars. Conglomerates and cement-based concretes were used for throwing pitches in even thicker castings. In some subsequent renovations, bricks were also used. The photographic and digital relief was carried out using laser scanner methodologies, which has allowed to define the conservation status of the Opera Punta Rossa complex, producing a 3D model of the current state of building.

"The Minoan site at Bramiana in southeastern Crete provides evidence for a Bronze Age economy based on trade, agriculture, and craftwork. This publication uses a new system of organizing the pottery by petrography-sorting it by materials and workshop practices-revealing a trade network of cooking pots and other clay vessels and their contents"--

One of the aims of the 2016 campaign in as-Sila was to conduct a survey in order to identify cisterns, channels and structures related to water use at the top of the settlement, using the 2015 survey map of the site as a base. The investigations have revealed a complex and sophisticated hydrological network with a great diversity of water structures (carved in the sandstone and designed for the collection, storage, transport and distribution of rainwater). All the structures have been identified and described using a total station, their location associated with the general topography of the site, and the contexts photographed. This study presents the results of recent analyses of lime-based mortars from rock-cut hydraulic structures collected during the 2016 archaeological campaign at the site of as-Sila/Sela, in the governorate of Tafilah in southern Jordan. Mineralogical and petrographic analyses were performed on 16 samples of mortars by means of x ray diffraction (XRD) and thin-section petrography (OM), and 12 AMS radiocarbon dates were taken from them. In spite of the difficulties in dating lime-based mortars and the problems inherent in the interpretation of the data, here we present the most complete analysis currently available of mortars from an archaeological site in southern Transjordan. ; The Sela Archaeological Project, led by R. Da Riva of the University of Barcelona (UB) in collaboration with the Department of Antiquities of Jordan (DoAJ), has been funded by the ICREA Academia Research Award, the Spanish Ministry of Education and Culture, the Agència de Gestió d'Ajuts Universitaris i de Recerca, AGAUR, of the Autonomous Government of Catalonia, and the PALARQ Foundation. The project also has the support of the Spanish Embassy in Amman. Except where otherwise noted, all photographs and materials published here are ©Sela Archaeological Project. The authors would especially like to thank Bob Bewley and Matthew Dalton of The Aerial Archaeology in Jordan Project for allowing us to use the aerial images taken in Sela in October 2018 (©APAAME). We would also like to thank María Soto and Josep Vallverdú who made the petrographic and mineralogical analyses at the IPHES and who most kindly put this information at our disposal. These analyses, as well as the 14C analysis at the CNA were financed by research grants of the PALARQ Foundation to which the authors express their most sincere gratitude.