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Este artigo analisa a sequência de ocupação registada nas escavações realizadas na área arqueológica do Ex Albergue Distrital, em Braga. Os trabalhos de arqueologia preventiva aí realizados permitiram identificar vestígios integrados num quarteirão da cidade romana, pertencentes a uma domus, construída na época flávia, que se dispunha a nascente do cardo máximo. Foi igualmente possível identificar as reformas operadas na domus nos finais do século III/inícios do IV, a progressiva alteração dos espaços da habitação na Antiguidade Tardia, bem como os sucessivos saques dos muros do edifício realizados na Alta e Baixa Idade Média associados à construção das cercas medievais erguidas nas imediações da área intervencionada. 

Este traballo céntrase na identificación dun parcelario histórico singular: o dextro, destral ou diestral; un elemento presente na toponimia actual e que se pode rastrexar na documentación histórica galega e estudada tanto por historiadores medievalistas como por xuristas, pero que pasou inadvertido para os estudos arqueolóxicos. Rastréxase a orixe histórica do destral, xustifícase o seu análise como elemento de estudo e se procede a súa identificación describindo a metodoloxía empregada, para finalmente delimitar fisicamente nove casos de estudo e comparalos resultados métricos coa información procedente das fontes históricas.

El yacimiento de A Pousada, excavado en un contexto de arqueología de urgencia, es un despoblado altomedieval, cuyas fases posteriores suministraron un conjunto de materiales cerámicos vidriados adscribibles a época bajomedieval y moderna. En el presente trabajo se muestran los resultados del estudio de una parte de los mismos, centrándose principalmente en el estudio arqueométrico. Las características de sus pastas nos aportan información sobre sus técnicas de factura así como su posible fabricación exógena, datos de vital importancia para comprender el comercio cerámico del momento.

In the Tafí del Valle region, in northwestern Argentina, several intrusive bodies of lower Paleozoic age were emplaced in the metasedimentary Puncoviscana Formation, belonging to the Sierras Pampeanas. Four intrusive bodies outcrop in the study area: La Ovejería, El Infiernillo, Loma Pelada and Los Cuartos. La Ovejería and El Infiernillo intrusive bodies represent the I-type magmatism according to their major element contents and show cotectic evolutions similar to those described by Famatinian I-type batholiths. These moderately peraluminous adakitic trondhjemites have characteristic high Sr/Y ratios and low Fe2O3+MgO+MnO+TiO2 contents. They are related to high-pressure conditions at the source, where dehydration melting of basaltic rocks may be involved and garnet is retained in the residue leading to generation of HREE depleted melts. The Loma Pelada granites show characteristics of S-type magmatism (low CaO and MgO, and high SiO2 and K2O contents) typical of granites segregated in the last stages of magmatic differentiation, or anatectic granites. They show an increasing peraluminosity due to garnet entrainment and they are related to the anatectic melts generated in the Puncoviscana Formation. Both the Loma Pelada and Los Cuartos granitoids include samples with intermediate geochemical characteristics that range between those of the El Infiernillo and La Ovejería and the regional metasedimentary rocks. These characteristics could be explained by assimilation processes involving the I-type intrusive magmas and the metasedimentary host rocks or by hybridization processes between trondhjemitic I-type magmas as La Ovejería and El Infiernillo and anatectic S-type melts.

Mudstones in the Sha-3 member of the Shahejie Formation, in the Tanggu area of the Huanghua Depression, have been found to contain analcime and ankerite. Hydrothermal sedimentation has been invoked to explain the origin of these two minerals, raising the question of whether hydrothermal activity occurred at a sufficient scale to significantly raise the salinity of the depositional environment. We applied a suite of organic petrological and geochemical methods to directly address this question. Maceral composition, kerogen type, and the distribution of n-alkanes, hopanes, and steranes indicate that the organic matter contained in these mudstones and dolomitic mudstones is mainly derived from algae and bacteria. The dominant acritarch genera, C31R/C30 hopane ratio, gammacerane index, Pr/Ph ratio, and the relationship between Pr/n-C17 and Ph/n-C18 suggest that the mudstones and dolomitic mudstones were deposited in an anoxic, saline lacustrine environment. Tmax, biomarker maturity indices, the Thermal Alteration Index (TAI) and Acritarch Alteration Index (AAI), and vitrinite reflectance all indicate that the organic matter is at an immature to early mature stage. The estimated maximum paleotemperature is close to the present-day burial temperature, and much lower than the homogenization temperature of the analcime veins in dolostones. Combined with the absence of unresolved complex mixtures on the n-alkane pattern, this suggests that hydrothermal activity had a negligible impact on the salinity and alkalinity of the depositional lake.

Small perch-like fishes from the Oligocene of the Paratethys have been traditionally assigned to Serranus budensis (Heckel, 1856). A morphological revision of the holotype and specimens previously assigned to S. budensis from the Outer Carpathians, Poland, is provided herein. They are re-assigned to the species Oligoserranoides budensis (Heckel, 1856) — Percoidei incertae sedis. New specimens assigned to Ol. budensis from the Outer Carpathians, Poland, are introduced. Our results reveal that Ol. budensis is very similar to the species Caucasoserranoides morozkiensis, Carpathoserranoides brnoensis, Carpathoserranoides polonicus and Oligoserranoides comparabilis, and further studies are necessary to revise the validity of those species. Ol. budensis shares many characters with genera Lutjanus and Ocyurus of the superfamily Lutjanoidea. Ol. budensis differs from Lutjanoidea in having a toothless palatine. The palaeobiogeography of Oligocene small perch-like fishes in the Paratethys is presented and discussed.

The Pivehzhan iron deposit is located at about 80km southwest of Mashhad, NE Iran. They occur within the Devonian carbonates as lenticular and massive bodies, as well as veinlets of magnetite and iron sulphides, transformed to goethite and haematite by weathering process. The hydrothermal calcite is the most important gangue mineral, which is observed in the form of veins/veinlets and open-space filling. The iron ores are accompanied by some minor elements such as Mn, Ti, Cr, and V and negligible amounts of Co and Ni. The distribution pattern of Rare Earth Elements (REEs) normalized to Post Archean Australian Shale (PAAS), which is characterized by the upward convex, as well as the positive Eu anomalies indicate the activity of reduced and acidic hydrothermal fluids. The negative Ce anomalies of host carbonates, although slight, point to the dominance of anoxic conditions during interaction with hydrothermal fluids.The hydrothermal calcite and quartz coexisting with the iron minerals contain principally fluid, which were homogenized into liquid phase. The homogenization temperature (TH(L-V)) and the salinity of the analysed fluid inclusions range from 129°C to 270°C and from 0.4wt.% to 9.41wt.% NaCl eq., respectively. The δ13CPDB and  δ18OSMOW values ranges from -2.15‰ to -5.77‰ (PeeDee Belemnite standard, PDB) and from +19.87‰ to +21.64‰ (Standard Mean Ocean Water standard, SMOW) in hydrothermal calcite veinlets occurring with iron minerals and -0.66‰ to -4.37‰ (PDB) and +15.55‰ to +20.14‰ (SMOW) within the host carbonates, respectively.The field relations and petrographic examination along with geochemical and isotopic considerations indicate that the Pivehzhan iron deposit was formed through replacement processes by reducing and acid fluids containing light carbon and oxygen isotopes. Variations in the physico-chemical conditions of hydrothermal fluids and their interaction with carbonates were the most effective mechanisms in the formation of this iron deposit. The potential source of iron was probably the basement magmatic rocks from which iron was leached by hydrothermal solutions.