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This article investigates the mechanisms by which different communities were articulated during the Late Intermediate period (ca. AD 1000–1450) in the Río Grande de San Juan Basin, also called the Chicha Region, located in the border region of Bolivia and Argentina. Through analyses of systems of pottery production, circulation, and consumption, we examine interaction networks, social integration, and alliance building at a regional level. Yavi-Chicha pottery from two sites in the Chicha Region—Chipihuayco, in the Talina Valley (Bolivia), and Finispatria, in San Juan Mayo (Argentina)—provide key insights into regional integration and constellations of practice through their localized technological style and shared consumption strategies. This study reveals that people of Finispatria incorporated the entire Yavi-Chicha-style household assemblage—partly produced in Chipihuayco, partly in Finispatria, or partly at some unknown location—into their everyday lives. We argue that the entire household ceramic repertoire of the study region played a fundamental and socially integrative role as it circulated across the region. [ABSTRACT FROM AUTHOR]

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Copyright of Trace: Travaux et Recherches dans les Amériques du Centre is the property of Centro de Estudios Mexicanos & Centroamericanos and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se presentan los resultados obtenidos del análisis del material cerámico proveniente del sitio Las Escondidas (Quebrada de Miriguaca, Puna Meridional Argentina) con el objetivo de abordar las características de la producción cerámica de los primeros momentos del Formativo (entre ca. 2000 AP y 1700 AP), para así tratar de indagar en el contexto social en el que esta cerámica fue producida y usada. Para ello se proponen dos etapas de análisis, la primera a través del uso de lupa binocular y la segunda, mediante análisis petrográficos. Los resultados obtenidos permitieron establecer las características y la posible funcionalidad del repertorio cerámico, además de lograr determinar la composición de las pastas. Se identificaron ciertas elecciones tecnológicas constantes y una importante homogeneidad en el uso de materias primas específicas, que no han podido ser correlacionadas directamente con el entorno geológico local. Posteriormente, a partir de la detallada descripción petrográfica, se pudo comparar este conjunto con otros analizados previamente, tanto de la Puna meridional argentina como de otros sectores circundantes, contribuyendo a establecer redes de relaciones en las cuales los objetos se vieron inmersos en los primeros momentos de la era.

En este trabajo se presentan los resultados sobre el estudio de las técnicas de manufactura involucradas en la producción alfarera del sitio Tambería de Guandacol, departamento de Felipe Varela, provincia de La Rioja (Argentina). Las piezas cerámicas se corresponden con el Estilo Sanagasta/Angualasto, asociado fundamentalmente a la época prehispánica tardía en el Noroeste Argentino (siglos XIII-XVII d.C.). A partir de un registro esencialmente fragmentario y mediante la combinación de estudios traceológicos y de petrografía cerámica, se pretende avanzar en el conocimiento de la cadena operativa y organización de la producción alfarera de los grupos que habitaron el valle durante dicho lapso. Asimismo se discuten los alcances y limitaciones de este tipo de estudio sobre registros fragmentarios. Los resultados han permitido registrar una elección uniforme de técnicas primarias y secundarias para la confección de recipientes y cierta irregularidad en los modos de aplicación. Igualmente, se reconocen semejanzas tecnológicas con producciones contemporáneas del área. El panorama permite plantear la existencia de un proceso de fabricación generado por un mismo grupo comunitario, con diferentes agentes involucrados y enmarcados en una tradición tecnológica basada en prácticas de enseñanza/aprendizaje cotidianas, con fuertes lazos sociales y culturales.

A Bacia São José do Itaboraí é uma depressão elíptica fechada encravada em rochas do embasamento cristalino, sendo sua origem associada ao desenvolvimento do Sistema de Rifte continental do sudeste do Brasil. A bacia foi preenchida principalmente por sedimentos carbonáticos e calcário travertino é a fácies predominante. Estudos mineralógicos através de microscopia de luz transmitida, difração de raios X e MEV/EDS e determinações de porosidade e permeabilidade foram efetuadas no travertino e nas fácies subordinadas brecha carbonática e grainstone oolítico, com o propósito de avaliar o sistema de porosidade de rochas carbonáticas. As investigações nessas três litofácies apontaram densidades entre 2,66 e 2,70 g/cm3 e taxas baixas a muito baixas de porosidade e permeabilidade, menor que 2,5% e 0,2 milidarcys, respectivamente. As principais causas para valores tão baixos residem na forte cimentação das rochas aliada à recristalização de cristais de calcita, à alteração de silicatos e ao preenchimento de poros por minerais diagenéticos. Este trabalho mostra que o fluxo de fluidos em rochas reservatório pode ser mais bem compreendido ao serem usados métodos de determinação mineralógica combinados com petrofísica.

En Mendoza (Centro-Oeste argentino), ciudad colonial meridional, los alfareros indígenas locales manufacturaron cerámica desde el siglo dieciséis, aunque su origen étnico fue documentalmente invisibilizado. La presencia de platos tipo Viluco Colonial en los contextos urbanos evidencia que los artesanos integraron técnicas locales, ligadas a la anterior dominación inca, con técnicas y formas de origen europeo. Con el objetivo de conocer las tecnologías de producción de los platos, realizamos análisis macroscópicos, petrográficos y con microscopía electrónica de barrido. A partir de esto, caracterizamos sus pastas, microfábricas y huellas de superficie. Proponemos que dichas vasijas fueron producidas tempranamente en la colonia por alfareros huarpes —sin excluir la posibilidad de participación de artesanos de otros grupos— quienes incorporaron el torno, pero continuaron con la tradición alfarera prehispánica y los lenguajes visuales andinos ligados al imperio inca. Analizar la producción cerámica como parte de la agencia social permitió visibilizar a los alfareros como agentes de cambio en la conformación de las nuevas identidades y culturas coloniales mendocinas, ya que sus productos híbridos pudieron ser usados por los colonos europeos, generando transformaciones identitarias como parte del proceso de etnogénesis. [ABSTRACT FROM AUTHOR]

During the prehispanic late occupations (ca. 1000-1500 AD), the Peña del Medio (Paicuqui, microregion of Antofagasta de la Sierra, Province of Catamarca), had a strong ritual connotation linked to astronomical observations and cult of the ancestors and, related to micro and macrorregional interaction practices. This paper presents the results obtained from stylistic and petrographic studies of the ceramics recovered on the place. An important stylistic variability in the vessels, their elaboration with allochthonous raw materials and the predominance of suitable forms for food consumption is detected. Ceramic similarities of the Antofalla region and of different sectors of the Calchaquíes valleys are recognized. It is concluded that the ceramic set is consistent with the interpretation of Paicuqui as a meeting place and interaction mediated by ritual practices. [ABSTRACT FROM AUTHOR]

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Copyright of Gestión y Ambiente is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There are several organic matter-rich shale geologic formations in Mexico that could be considered non-conventional potential oil reservoirs; one of those formations is the Eagle Ford Formation (Late Cenomanian - Turonian), aim of this study. The Eagle Ford Formation is located within the Sabinas paleobasin and along the Burros-Peyote paleoplatform, in the Coahuila State. This formation has been previously described as a transgression system deposited in a shallow marine environment with a total organic carbon between 0.5 to 8% with type II organic matter. For these reasons, it could be considered a potential source for non-conventional hydrocarbons. Therefore, it is considered that a reservoir of shale gas must have certain requirements, such as: 1) high total organic carbon (> 2% of COT), 2) presence of types II and III kerogen, 3) vitrinite reflectance values greater than 1.2% Ro (0.7% for shale oil), 4) thickness greater than 30 m and large extension, 5) fracturability (<40% clays or absence of expandable clays) or the presence of a microcracking system, 6) overpressure, 7) adequate depth, 8) heterogeneity, and others. A systematic sampling was carried on outcrops of Coahuila State with the goal to determine the thermal maturity degree of the Eagle Ford Formation using a detailed stratigraphic analysis of three columns (CSI, CSII and CSV) and micro-thermometric of fluid inclusions. Our results indicate that the Eagle Ford Formation is a sedimentary sequence rich in organic matter, locally composed of carbonaceous carbonate shale in laminar stratification alternating with shaly limestone (mudstone- wackestone) and clastic o bioclastic limestone (packstone-grainstone). Regarding the diagenetic alteration, primary porosity is affected by compaction and cementation processes. However, it was also observed a secondary micro-porosity development due to neomorphism, dolomitization, fracturing and stylolitization processes. Measured homogenization temperatures (Th) in fluid inclusions are between 65 °C and 125 °C, reaching the temperature window to generate oil and humid gas. The thermal evolution through its facies changes in the basin is not homogeneous. Our results indicate that the Eagle Ford Formation is a sedimentary sequence rich in organic matter, locally composed of carbonaceous carbonate shale in laminar stratification alternating with shaly limestone (mudstone- wackestone) and clastic o bioclastic limestone (packstone-grainstone). [ABSTRACT FROM AUTHOR]

The article presents the analysis of the correlation between the self-ignition parameters and the ultimate and proximate analysis, as well as the petrographic properties of Polish lignite, sub-bituminous coal, bituminous coal and anthracite. The following coal properties were determined: the moisture, ash content, volatile matter and sulfur content, gross calorific value, net calorific value, C, O, N and H contents, total porosity, ash oxide composition, rates of spontaneous combustion in 237°C and 190°C, and activation energy. During the petrographic analysis, maceral composition and random reflectance were determined. To determine the linear correlation between the self-ignition parameters and the analyzed coal properties, the Pearson correlation coefficient was calculated. The results show that there is no strong linear correlation between the lignite tendency to self-ignition and its petrographic properties. However, a strong negative correlation between the rate of spontaneous combustion and moisture and volatile matter content was observed. In the case of bituminous coal, strong correlations between self-combustion parameters and various coal properties were confirmed. The most noteworthy are the correlations between self-ignition parameters and the maceral composition, that is, between the content of macerals of the inertinite group in coal and content of macerals of the huminite/vitrinite group. The obtained results suggest that the spontaneous combustion tendency of coal increases with the increasing content of semifusinite and liptinite. [ABSTRACT FROM AUTHOR]

Copyright of Comunicaçõe Geológicas is the property of Laboratorio Nacional de Energia e Geologia, I.P. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The rocks of interest in the present study (mudstones) show inherently a heterogeneous pore-size distribution in the matrix. They can present organic and inorganic pores and the transport mechanism through pores is different, and, therefore, it is necessary to describe their organic and inorganic porosity. This work uses different microscopy techniques to characterize mudstones from the Galembo Member of the Cretaceous La Luna Formation, Middle Magdalena Valley Basin, Colombia. These rocks present several pore types, including interparticle pores due to flocculation of clay minerals, organoporosity due to burial and thermal maturity, intraparticle pores from organisms, intraparticle pores within mineral grains, and microchannels and microfractures. The existence of interconnected pores in such complex fracture-pore system provides effective pathways for primary gas migration and it also provides a storage space for the residual hydrocarbon in mudstones, which is important for the primary migration and storage in gas reservoir rocks. The pore connectivity is high and increases towards the top of the sedimentary sequence. [ABSTRACT FROM AUTHOR]

The Choiyoi Group from the Permo-Triassic, is one of the most conspicuous volcano-sedimentary suites of southern South America, considered critical to understand the geological evolution of the western margins of Gondwana. In this regard, petrography, geochemistry, and structural data were examined to better elucidate the physical character and emplacement conditions of the unit in the Cordón del Plata range, within the Frontal Cordillera of Mendoza, Argentina. The site is representative of the magmatism and deformation through different Andean cycles. Results of the study indicate three facies of increasing felsic composition upwards. Mafic units consist of basalts, andesite and andesitic breccias at the base of the sequence. Felsic rocks such as rhyodacites, granites and welded tuffs are predominant above. The fault zone of La Polcura -- La Manga is the most prominent structural feature in the region, which presumably controlled the emplacement of breccias and ignimbrites within the middle and upper members. These compositional variations suggest a magma evolution from subduction to a rifting environment after the San Rafael orogeny in the Late Palaeozoic. In this line, the Lower Choiyoi was observed to overlie the San Rafael structures indicating thus, that compression ceased before the volcanic extrusion. Geochemistry data indicate that mafic rocks are mostly high-potassium, calc-alkaline volcanics derived from the mantle wedge above the subduction zone. In contrast, the Upper Choiyoi corresponds to high-potassium rhyolites to shoshonites, typically depleted in Eu. This indicates partial melting of a lithospheric mantle in an average to thin crust. [ABSTRACT FROM AUTHOR]

In this article we present the results obtained from the macro and microscopic analysis of the pottery assemblies of four sites located in the Copacabana river basin (Ischilín, Córdoba, Argentina). The purpose of this study is to investigate the different ways of manufacturing ceramics. Firstly, a typology was elaborated, and then the variability of the identified groups was tested trough the implementation of petrographic techniques. Based on these first analyzes, four petrographic groups were identified which indicate a difference in the addition of antiplastic in ceramic pastes and, therefore, different ways of making pottery are inferred. [ABSTRACT FROM AUTHOR]

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Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Se presentan los resultados de la caracterización estilística y del análisis tecnológico y petrográfico sobre conjuntos cerámicos recuperados en el sitio Los Viscos, valle del Bolsón (Departamento de Belén, Provincia de Catamarca). Se trata un alero que fue reocupado de manera discontinua pero recurrente entre un lapso ca. 1.000 AC - 1.440 DC y fue utilizado como refugio temporal vinculado con actividades de tránsito interregional. Los restos de alfarería que quedaron como resultado de dichas ocupaciones corresponden a los períodos Formativo, Desarrollos Regionales e Hispano Indígena. Se realiza un análisis sincrónico y diacrónico de los mismos con el propósito de contribuir por un lado, al estudio de las prácticas de producción cerámica en el valle y además, brindar evidencia para vincular al sitio con actividades de interacción con diferentes regiones. De este modo, se problematiza la procedencia de las piezas recuperadas y se sugiere una circulación diferencial entre la cerámica fina y la ordinaria que se reproduce a lo largo de la secuencia.

A fin de realizar una primera aproximación a la procedencia de materias primas cerámicas de la cuenca sur de Pozuelos, se realizan comparaciones petrográficas entre pastas cerámicas, analizadas en trabajos previos, y muestras de arena procedentes del área de estudio. Las mismas fueron preparadas y estudiadas tanto en lupa binocular como en microscopio petrográfico, considerando atributos semejantes a los observados sobre las pastas cerámicas. Asimismo, se revisó la literatura geológica del área. Las comparaciones realizadas permiten hipotetizar que un conjunto de pastas cerámicas, abarcando varios grupos de pastas de composiciones relacionadas, habrían sido manufacturados con materias primas locales, dada la similitud en las características petrográficas de sus inclusiones y los clastos de las arenas. Otro conjunto, relacionado al estilo Yavi, sería no local para el sur de Pozuelos. Finalmente, un conjunto menor de pastas serían de momentos posteriores al contacto hispano indígena y también probablemente no locales.

En el presente artículo, se describen los resultados de un proyecto de investigación llevado acabo para caracterizar las propiedades fisicoquímicas de cinco tipos de roca volcánica (riodacita), comúnmente conocida como "cantera", tradicionalmente utilizada para la construcción y restauración de edificios históricos en la ciudad de Oaxaca, México. En el programa experimental, se analizaron cinco tipos de piedra para conocer sus características mineralógicas y petrográficas mediante fluorescencia de rayos X y análisis petrográfico. De la misma manera, se llevaron a cabo pruebas de resistencia a la compresión, densidad y absorción. Finalmente, los resultados obtenidos en el programa experimental fueron analizados y correlacionados con las propiedades de resistencia y durabilidad de los cinco tipos de piedra evaluados.

El objetivo de este trabajo es caracterizar tecnológicamente el conjunto cerámico de El Sequero (Arrúbal), yacimiento de fondos de cabañas del siglo IX cal BC. El conjunto reproduce formas características del Bronce Final en el valle medio de Ebro, con decoraciones plásticas, motivos acanalados, incisos y excisos. La caracterización mediante análisis petrográfico de una selección de muestras del conjunto cerámico ha permitido identificar dos grupos que se corresponderían con distintas ‘formas de hacer’ en cuanto al aprovisio- namiento de la materia prima y el procesado de las arcillas. Su comparación con yacimientos del País Vasco y de Aragón permite integrar y comparar el conjunto con otros grupos tecnológicos del alto y medio valle del Ebro. Los resultados indican una conexión con las elecciones tecnológicas detectadas en otros yacimientos del alto valle, mientras hay notables diferencias con los del valle medio, como el Cabezo de la Cruz de La Muela (Zaragoza).

Os Stocks Monte Pedral, Boa Esperança, Santa Maria, Niterói e Bom Jardim situam-se na parte Norte do Sistema Orogênico Sergipano. Esses cinco corpos são constituídos por: álcali-feldspato sienito e quartzo álcali-feldspato sienito (Monte Pedral); quartzo álcali-feldspato sienito e álcali-feldspato granito (Boa Esperança); granito (Santa Maria); monzogranito, quartzo monzonito e quartzo monzodiorito (Niterói); granito, quartzo monzonito, granodiorito, quartzo monzodiorito e diorito (Bom Jardim). Essas rochas são porfiríticas, com megacristais de feldspato alcalino rico em zoneamentos oscilatórios. A ocorrência de megacristais de feldspato alcalino com zoneamento composicional bem marcado e enclaves máficos é uma feição que distingue esse magmatismo daqueles de outras suítes intrusivas do Domínio Canindé. Os Stocks Monte Pedral e Boa Esperança correspondem a um magmatismo hipersolvus, enquanto os demais Stocks (Bom Jardim, Niterói e Santa Maria) representam magmatismo subsolvus. A idade U-PbShrimp de 611 ± 4 Ma obtida para o Stock Santa Maria permite correlacioná-lo ao plutonismo shoshonítico mais antigo no Sul da Província Borborema. A mica marrom nas rochas corresponde à biotita e flogopita e indica afinidade orogênica para este plutonismo. A Mg-hornblenda e a tschermakita são os anfibólios primários nestas rochas, os quais cristalizaram-se em condições oxidantes e em profundidades que variam de 12 (3 kbar) a 26 (7 kbar) km. Dados geoquímicos revelam que os magmas responsáveis por formarem os stocks estudados pertencem a suítes shoshoníticas e evoluem por cristalização fracionada, tendo contribuição de material mantélico, além de exibirem assinatura geoquímica (enriquecimento em Elementos Terras Raras Leves), em relação aos pesados, e anomalias negativas em Ta, Nb, P, Sr e Eu, características de magmas associados à subducção.

Lo scavo nel parco di Villa Belmonte (Monte Pellegrino, Palermo) ha messo in luce diversi ambienti, realizzati con una tecnica a “pseudo telaio” probabilmente con copertura straminea, adoperati per lo stoccaggio di derrate data la grande quantità di anfore di tipo punico rinvenute in situ, databili intorno alla metà del III sec. a.C. Inoltre, si è intercettato un tratto di strada larga circa 3 m che procede in direzione WNW- ESE, costituita da due battuti. Si ritiene di avere rintracciato parte di una postazione a carattere strategico/militare utilizzata dall’esercito cartaginese durante gli anni cruciali della I guerra punica.

No sudoeste do estado da Bahia, entre as cidades de Brumado e Caetité e mais a norte próximo às cidades de Tanque Novo, Paramirim, Botuporã, Macaúbas, Novo Horizonte e Ibitiara, ocorrem diques máficos formados em ambiente intraplaca. São toleítos continentais apresentando valores de índice de diferenciação em magnésio (mg#) entre 0,25 e 0,45, indicativos de líquidos magmáticos evoluídos. Plagioclásio e augita predominaram no processo magmático evolutivo, cujos diagramas não mostram alterações significativas por processos secundários. Os diques máficos originaram-se de fonte pouco heterogênea tipo Enriched Mid-Ocean Ridge Basalt (E-MORB), provavelmente com leve contribuição de fluidos tipo Ocean Island Basalt (OIB). Os dados geoquímicos sugerem influência significativa da crosta continental inferior na origem da fonte mantélica, não havendo sinais de importante contribuição sedimentar.

O termo Granito Aripuanã refere-se a um conjunto de corpos graníticos circunscritos não deformados, intrusivos em rochas da sequência metavulcanossedimentar do Grupo Roosevelt, reconhecidos na porção sul do Cráton Amazônico. O corpo granítico principal constitui um batólito ovalado com diâmetro menor que 15 km, que ocorre a norte da cidade de Aripuanã, no noroeste do estado do Mato Grosso. É constituído de hornblenda-biotita sieno a monzogranitos porfiríticos grossos, de coloração cinza ou vermelha e localmente com texturas rapakivi. Nas áreas marginais é observada uma redução de granulação das feições porfiríticas com predomínio da fácies equigranular fina, associada a resfriamento rápido. As fácies tardias comuns são constituídas de diques equigranulares de cor cinza, aplitos róseos e cinza e veios pegmatíticos. Ocorrem veios pós-magmáticos de quartzo, fluorita, muscovita em zonas de deformação rúptil, em que as rochas mostram intensa alteração hidrotermal. Esse hidrotermalismo afeta de forma heterogênea as rochas encaixantes e as rochas magmáticas, facilitando a circulação de fluidos e favorecendo a concentração de sulfetos de zinco disseminados, sempre relacionados ao fraturamento. Os granitos hospedam xenólitos de rochas paraderivadas encaixantes, de granodioritos, quartzo dioritos e rochas micáceas. Nas bordas, ocorrem veios e apófises graníticas, além de metamorfismo de contato nas rochas encaixantes. Os monzogranitos são peraluminosos e pertencem à série de alto potássio a shoshonítica, similares a granitos “ferroan”, apresentando assinatura de granito tipo A, pós-colisionais a anorogênicos e associado à evolução do Arco Magmático Jamari.

Os Stocks Propriá, Amparo do São Francisco e Fazenda Alvorada são intrusivos na parte leste do Domínio Macururé e truncam a foliação regional. Esses corpos apresentam feições geológicas e petrográficas semelhantes e são composicionalmente constituídos por quartzo monzonitos e granitos porfiríticos. Nesses plutons, a biotita é o mineral máfico predominante e hornblenda ocorre em alguns enclaves associados. Os cristais de plagioclásio exibem forte zoneamento, indicando instabilidades durante a cristalização magmática. Os minerais acessórios nessas rochas são apatita, zircão, titanita, minerais opacos. Nos Stocks Propriá e Amparo do São Francisco enclaves máficos microgranulares são abundantes. A idade de cristalização do Stock Propriá é de 615 ± 6 Ma (U-PbShrimp). Os dados geoquímicos indicam que esses stocks correspondem a magmas potássicos, gerados em ambiente orogênico e alojados na crosta em período pós-colisional.

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Copyright of Geologia USP: Série Científica is the property of Geologia USP and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We present the results about the last researches carried out on ceramic fabrics of Las Garzas, an Early site (600 a.C.-650 d.C.) located in the Lerma Valley (Province of Salta, Argentina). This approach implied a revision of previous studies initiated by Cremonte (Cremonte et al., 1987), which allowed us to adjust the petrography of the ceramic pastes, expanding the analyzed sample and completing the previous analyzes incorporating different recording procedures. Data obtained in relation to the local geology allowed us to hypothesize about foreign or in situ production of the vessels represented in the studied sample. Likewise, comparisons with other pottery groups from the Lerma Valley and more distant pottery traditions such as Tafí and San Francisco valleys, allowed us to evaluate links in the manufacturing techniques that contribute to our knowledge about early pottery technological traditions in Northwestern Argentina. [ABSTRACT FROM AUTHOR]

During the first millennium B.C. finely decorated Cupisnique Rojo Grafitado bottles appeared in small numbers on different sites of north-central Peru. Petrographic and portable digital microscopy of the paste, chemical analysis of the pigments, and stylistic studies point to a production in the hands of specialized potters sharing similar paste recipes and technology of manufacture, but not resources, and working independently in different workshops. Mineral composition and granulometry are similar for vessels found on different sites, pointing to the use of crush rock temper or sediments rich in intrusive rock fragments probably derived from outcrops in the northern coastal batholith. Shiny black designs over a highly polished red slipped surface gave the name to the style but recent analysis showed that not all designs were done with graphite. Scanning Electron Microscopy (SEM-EDS) analysis revealed that, at least in one case, the black pigment used for surface decoration was manganese, while in seven other cases high C peaks, low Fe peaks, and no Mn were detected. For these wares, this suggests surface carbonization in reduced conditions. In Kuntur Wasi, the Cupisnique Grafitado style was imitated on other forms and style variants. [ABSTRACT FROM AUTHOR]

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From an archaeological perspective, the practice of pottery making can be studied from different theoretical and analytical perspectives on the stages of pottery production. In this paper, we present the results obtained through technological analysis of prehispanic pottery from the Costa de Reyes N° 5 archaeological site (Tinogasta, Catamarca). The main goal of this analysis is to explore the pottery-making practices developed by ancient potters during the Late Period and through the arrival of Incas at the southern sector of Abaucán Valley. Our methodology consisted of the reconstruction of typical ceramic forms, the use of a stereoscopic microscope to study fresh transversal cuts, and thin-section analyses by ceramic petrography, carried out on pottery samples recovered from both surface collection and excavations in two structures at Costa de Reyes N° 5. Through this approach, we are able to explore and visualize continuities and ruptures in both the pottery-making practices and paste recipes during the Late Period (ca. 900-1450 aC), and how pottery-making was reconfigured when the Inca (ca. 1480-1532 aC) arrived in the region. While pottery production during the Late Period is characterized by technological variability and heterogeneous ceramic pastes, during Inca times there was a homogenization of the recipes used by ancient potters. This is interpreted as a strict control of both the raw materials available and over the pottery production as a whole. [ABSTRACT FROM AUTHOR]

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Entender o comportamento mecânico de enrocamentos é, antes de tudo, garantir a segurança dos seres que residem à jusante de barragens. A Usina Hidrelétrica Machadinho teve sua construção finalizada no ano de 2002, tendo como principal característica a inserção de basalto vesicular em até 30% da constituição do corpo do aterro principal, cuja litologia predominante é o dacito. Os trabalhos mais recentes, disponíveis na literatura de enrocamento, têm alertado sobre a alterabilidade das propriedades mecânicas das rochas, uma vez que obras de barragens possuem tempo de vida útil muito longo. Este trabalho teve como objetivo avaliar as estruturas e mineralogia dos enrocamentos de Machadinho. Foram realizadas microscopias eletrônicas e análises petrográficas, tendo-se ainda avaliado os componentes químicos em áreas específicas por meio de espectrometria de dispersão. As constituições mineralógicas dos enrocamentos da UHE Machadinho indicaram elevadas porcentagens de vidro vulcânico nas estruturas, sobretudo o basalto vesicular, direcionando-se para a necessidade da avaliação da ação do intemperismo ao longo do tempo no comportamento mecânico deste material, como garantia de segurança da barragem.

La cueva de Berroberria es uno de los yacimientos más representativos del Magdaleniense en el Pirineo Occidental. Se presentan en este caso los resultados del estudio de procedencia de las materias primas líticas empleadas por los grupos del Magdaleniense Medio (alrededor de 14500 cal. BC). La metodología propuesta incluye análisis petrológicos y mineralógicos, mediante los que se identifican los principales afloramientos de sílex de los que se abastecieron. Se ha constatado así la explotación mayoritaria de los recursos silíceos más cercanos, como es el sílex de Flysch, junto con la de recursos regionales, como los sílex de Tercis o Chalosse, y siendo minoritarios pero de gran interés los aportes de materias primas extra-regionales de posible procedencia noraquitana. La gestión de cada una de estas rocas, al igual que su representación, es diferente; pero concuerda con la dinámica observada para esta cronología.

Lamprófiros ocorrem como enclaves microgranulares no Stock Monzonítico Glória Norte (SGN) (588 ± 5 Ma), localizado na parte central do Domínio Macururé, do Sistema Orogênico Sergipano, no estado de Sergipe. Esses enclaves lamprofíricos foram classificados como minettes e ocorrem concentrados em uma área com aproximadamente 1 km de diâmetro na região sudeste do stock. Os minettes apresentam texturas porfirítica e panidiomórfica, com fenocristais de biotita e matriz com granulação fina. Os minerais máficos presentes, além da biotita, são: diopsídio, augita, hornblenda e titanita. Ortoclásio pertítico, andesina, biotita, carbonato, apatita e zircão também estão presentes na matriz. Os dados dos elementos maiores (K2O/Na2O > 3, 6 > %MgO > 8, K2O > 3%), menores e traços (baixos valores de Ti, Nb, Ta) indicam magmatismo ultrapotássico orogênico. As razões Th/Yb > 9,00 e 0,05 < Ta/Yb < 0,20 apontam para magma formado por fusão de um manto enriquecido. As informações obtidas neste estudo indicam que magmas básicos ultrapotássicos estiveram presentes durante o período pós-tectônico no Sistema Orogênico Sergipano (SOS).

En este artículo se presentan las características texturales, petrográficas y micropaleontológicas de las distintas silicificaciones que afloran en el Pirineo centro-oriental. Para esta investigación se han analizado más de 300 muestras procedentes de 75 afloramientos primarios y subprimarios. Las descripciones son el resultado de un intenso trabajo de campo desarrollado en la última década en ambas vertientes de la Cordillera Pirenaica. El corpus de datos que presentamos provee detalladas descripciones de la totalidad de recursos silíceos disponibles en este área, facilitando futuras investigaciones arqueopetrológicas desarrolladas en el ámbito geográfico pirenaico. Finalmente, debido a las particularidades que poseen algunas silicificaciones y a su amplia difusión en el registro arqueológico, presentamos lo que hemos definido como dos trazadores litológicos del área pirenaica.

This paper presents the petrographic analysis of ceramic pastes from Formative archaeological sites (700 BC-1000 AD) in Quebrada del Toro (Salta, Argentina). The results allow us to define the presence of fifteen modes of ceramic paste, some of which persist throughout the entire period. The vast majority of the analyzed sherds were of local origin, while others refer to modalities that are characteristic of the pottery from different sectors of the southern Andean area, such as the San Francisco Valley (Jujuy) and San Pedro de Atacama (Chile). [ABSTRACT FROM AUTHOR]

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Copyright of Revista Mundo de Antes is the property of Revista Mundo de Antes and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)