RESUMEN El área suroeste de la costa ecuatoriana es una región tradicionalmente petrolera, sin embargo aún no se ha definido cuál es el sistema petrolero reinante en la región. Entre las principales rocas propuestas como generadoras de los crudos del litoral, se encuentran las formaciones Seca y Socorro del Eoceno así como Dos Bocas y Subibaja del Mioceno. Con la finalidad de aportar nuevos elementos al conocimiento de la zona, fueron estudiados tanto crudos como rocas provenientes de campos onshore y offshore, usando técnicas geoquímicas que incluyen cromatografía de gases e isótopos de carbono. Parámetros como el Índice Preferencial de Carbonos (IPC), Pri/ n-C 17 , Fit/n-C 18 y las distribuciones isotópicas, indican que los crudos de los campos onshore están genéticamente diferenciados de los crudos offshore, y se asocian con una roca madre clástica con aporte de materia orgánica mixta, depositada en ambiente subóxico, consistente con la parte distal de un complejo estuarino. Por otro lado, las rocas analizadas son inmaduras térmicamente y con muy bajo potencial generador, por lo que no pueden ser correlacionadas con los crudos analizados, tal y como se venía haciendo tradicionalmente. Palabras clave: geoquímica; roca madre; madurez térmica; Golfo de Guayaquil; Ecuador. Geochemical correlation between oils and rocks of the petroleum system of the Santa Elena peninsula and the gulf of Guayaquil ABSTRACT The southeastern of the Ecuadorian coast is a traditionally oil producing region, but the petroleum system has not been defined yet. The proposed main source rocks are Seca and Socorro formations (Eocene) and Dos Bocas and Subibaja formations (Miocene). In order to contribute new elements to the knowledge of the area, both crude and rock from onshore and offshore fields were studied, using geochemical techniques that include gas chromatography and carbon isotopes. Parameters such as the Carbon Preference Index (IPC), Pri/n-C 17 and Phy/n-C 18 ratios and the isotopic distributions, indicate that onshore oils are genetically differentiated from offshore oils and are associated with a detritic source rock with mixed organic matter, deposited in a suboxic environment, consistent with the distal area of an estuarine complex. On the other hand, the rocks analyzed are thermally immature and with very low generating potential, so that they cannot be correlated with the crude analyzed, as was traditionally done.

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Tar residues (“tarballs”) occur frequently on the SE coast of the Paria Peninsula, NE Venezuela. This paper reports on tarballs recovered from approximately 14 km of shoreline during monthly sampling over a two‐year period ending in April, 2011. The tarballs were analysed geochemically and results show that more than 70% of them could be included within a single compositional group on the basis of their physical and organoleptic properties. The tarballs were fingerprinted using biomarkers (hopanes, steranes, alkanes, aromatic steroids, phenanthrenes and dibenzothiophenes) by gas chromatography and gas chromatography – mass spectrometry. Sulphur and trace element contents were also determined. These analyses indicate that the tarballs do not have an anthropogenic origin, but that they probably originated from petroleum generated by argillaceous limestones in the Turonian – Campanian Naparima Hill Formation. This formation includes marls and organic‐rich shales and limestones, and is an important source rock at oilfields in Trinidad and the southern Gulf of Paria. In the southern part of the Gulf, petroleum escapes from Neogene reservoirs to the seafloor via natural seepages associated with the Los Bajos and other fault systems. It is inferred that the petroleum is then transported by wind and tidal currents to the coast of the SE Paria Peninsula where it strands as tarballs. The geochemistry of the tarballs collected is discussed to investigate their source.

Coal-forming environments require humid to perhumid conditions. Tectonics governs the size, location and availability of coal seams developed in such environments. While large Pennsylvanian paralic basins generated thick and continuous coal seams, many other small coeval basins, which were tectonically active, developed a puzzling succession, with carbonaceous deposits that varied in size, thickness and the nature of the coal-forming flora. This study, conducted in the Peñarroya-Belmez-Espiel coalfield, a Variscan strike-slip basin in the south of Spain, provides insights into this subject. The coal seams analysed, generated in different depositional environments, have quantitatively different palynological assemblages. Lacustrine coals are dominated by lycopsids; distal alluvial plain/marginal lacustrine coals are dominated by sphenophytes and tree ferns, and middle alluvial fan coals are dominated by sphenophytes, tree ferns and lycopsids. This means that when conditions were favourable for peat accumulation, peat accumulated regardless of the nature of the available flora.

A. está tratando los polvos de horno eléctrico de arco (EAFD) para recuperar el ZnO. Se estudian algunas alternativas para mejorar la obtención del ZnO por el proceso Waelz, y se presta atención a la preparación de la carga antes del proceso de reducción. La aglomeración de los EAFD en forma de pelets es una alternativa fundamental, y se considera también el lavado de los EAFD para eliminar los cloruros, fluoruros y alcalinos. Se obtienen buenos resultados en los tratamientos térmicos $z estos residuos en forma de pelets, con o sin reductor incorporado. Se estudia la volatilización del cinc, controlando la temperatura y el tiempo de reducción. Después del proceso de reducción, se obtienen pelets enriquecidos en hierro metálico que contienen elementos escorificantes susceptibles de ser reciclados al horno eléctrico de arco. Palabras clave: Residuos. Polvos de horno eléctrico. Proceso Waelz. Tostación reductora. Development of a cleaner technology for obtaining ZnO from wastes generated in steel manufacturing Abstract In SpáinV the company ASER, S.A. is currently treating electric are furnace dust (EAFD) in order to recover its ZnO contení. Several alternad ves are studied for improving the obtainment of ZnO by the Waelz process, paying attention to the preparation of the charge before the reducing process. Agglomeration of the EAFD in pellet form is a fundamental alternative, and consideration is also made of washing the EAFD in order to remove chlorides, fluorides and alkalines. Good results are obtained in the heat treatment of the EAFD in pellet form with and without incorporated reducing agent. A study is made of zinc volatilization, controlling the reducing time and temperature. After the reducing process, metallic iron enriched pellets are obtained which contain fluxing elements susceptible to reeyeling in the EAF.

Purpose The purpose of this work is to study coal samples from various exposed seams of the La Ballesta mine, at the southeastern edge of the Peñarroya-Belmez-Espiel coalfield, southwestern Spain. Shaly seat-and caprocks were also investigated. Method Petrographic, palynological, and biomarker analyses were carried out. The major elements were determined by X-ray fluorescence (XRF). The trace elements were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS). Results The Pennsylvanian (Westphalian)-age, high volatile bituminous coal studied is a humic coal with vitrinite concentrations of over 86% on a minerals-free basis and low amounts of liptinite and inertinite. The coals have a relatively higher volatile matter yields than the bituminous coals in western areas of the basin with similar vitrinite reflectance values and present both a dark and a light variety of vitrinite. The dark variety is more abundant in the low ash coals considered to have been formed in nearby lacustrine settings. The mineral assemblage of the coals and non-coal (roof and floor) rocks from the La Ballesta mine is dominated by quartz, kaolinite and illite, with minor to trace proportions of epigenetic carbonates, anatase, and K-feldspar, among others. Conclusions Concentrations of B and B/Be ratios, along with other data, suggest that the La Ballesta coals may have originated from topogenous mires that developed next to lacustrine settings. Coal seams 9, 9bis, and 14 were probably more restricted systems than coaly shale 15, the latter corresponding to swamps associated with alluvial and floodplain environments. Abnormally high concentrations of trace elements such as Li, Rb, Cs, Sc, V and Cr might be explained by the input of detrital minerals into the Peñarroya Basin from the outcropping Precambrian and Lower Palaeozoic rocks to the northeast. In this regard, elemental ratios such as Al 2 O 3 /TiO 2 for the samples suggest that the modes of occurrence of the trace elements, and the minerals, in La Ballesta coals and non-coal rocks are to be mainly attributed to detrital input from felsic to intermediate metamorphic rocks. Keywords Bituminous C coal Á La Ballesta mine Á Peñarroya-Belmez-Espiel coalfield Á Petrography Á Geochemistry Resumen Objetivo El objetivo de este trabajo es estudiar una serie de muestras de carbón de varios mantos aflorantes de la mina La Ballesta, en el margen suroriental de la cuenca minera de Peñarroya-Belmez-Espiel, suroeste de España. Las correspondientes lutitas infra-y suprayacentes también fueron investigadas. Métodos Análisis petrográficos, palinológicos y de biomarcadores fueron realizados. Los elementos mayoritarios se analizaron por fluorescencia de rayos X (XRF). Los

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