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The Holocene volcanism at El Hierro consists of basaltic monogenetic volcanic fields associated with o the three rift systems present in this island. In this work we report preliminary petrological and geochemical data of Holocene lava flows belonging to the WNW-striking rift. Sampling was focused in three zones: Orchilla, Verodal-Sabinosa, and Tanganasoga. Petrography of the studied lavas shows that they are homogeneous. All samples are porphyritic with macrocrysts of clinopyroxene and olivine immersed in a groundmass formed by microcrysts of plagioclase, Fe-Ti oxides and clinopyroxene. Clinopyroxenes are diopsides, olivines have forsterite contents ranging from 74 to 84 % and anorthite in plagioclase varies from 66 to 76% (labradorite). Whole-rock geochemical results evidence that all magmas are basic in composition, ranging from picrobasalts to phonotephrites. Major, trace elements and isotope support fractional crystallization as the main process of magma evolution. However, petrography and chemistry of clinopyroxene cores agree with a xenocrystic nature of some of them. We suggest that these clinopyroxene cores crystallized from a genetically related magma and subsequently were entrapped or cannibalized by the basic rising magmas. © 2019 Sociedad Geologica de Espana. All rights reserved. ; This work has been funded by the Agencia Canaria de Investigación, Innovación y Sociedad de la Información (Sol-SubC200801000047). It was carried out in the framework of the Research Consolidated Groups GEOVOL (Canary Islands Government, ULPGC) and GEOPAM (Generalitat de Catalunya, 2017 SGR 1494). ; Peer reviewed

The reservoir characteristics of the Pre-Santonian Eze-Aku sandstone were assessed using an integrated thin section petrography and SEM Back-Scattered Electron (BSE) imaging methods. Fresh outcrop data were collected in the Afikpo area (SE Nigeria). Twenty-eight representative samples from the different localities were analysed to obtain mineralogical and petrographical datasets germane for reservoir characterisation. Thin section petrography indicates that the sandstones are medium-grained, have an average Q90F10L0 modal composition, and are classified as mainly sub-arkose. The sandstones on SEM reveal the presence of cement in the form of quartz overgrowths, authigenic clays and feldspar. From epoxy-stained thin sections and/or SEM BSE image analysis, primary, secondary (inferred from partial to total feldspar dissolution/alteration), and micro- (in authigenic clays) porosity types were identified. Although the development of quartz overgrowths, authigenic clay precipitation, and feldspar dissolution often affect reservoir properties of sandstone negatively, the Eze-Aku sandstones still retained very good reservoir properties (porosity, average 22.7 %; permeability, average 745.43 mD). This can be attributed to the abundance of framework grains that have been stabilized by quartz cement and relatively limited feldspar dissolution. The stabilized framework grains help preserve reservoir characteristics and resist further compaction beyond eogenetic depths. The feldspar dissolution produced silica and aluminium that was precipitated to form the quartz overgrowths and the authigenic clays (e.g., kaolinite), respectively. The relatively concurrent precipitation of silica and aluminium from dissolution products reduces the quartz overgrowth quantity and authigenic clays that could have adversely affected the reservoir characteristics.

Half-title: The University of Minnesota. A report on the geological and natural history survey of Minnesota; made in pursuance of an act of the legislature of the state, approved Mar. 1, 1872. Pub. by the authority of the state. ; N. H. Winchell, State Geologist. ; Several plates accompanied by leaf with descriptive letterpress. ; Vol. 1; v.3, pts. 1-2, printed in Minneapolis. ; List of publications bearing on the petrography of Minnesota: v. 5, p. 76-78. ; Bibliography of Minnesota iron mining: v. 4, p. 613-616. ; Review of earlier literature on Lower Silurian fauna in the upper Mississippi Valley: v. 3, pt. 1, p. x-xlix. ; Mode of access: Internet.

The current research studies the depositional setting of the Jeribe Formation in the south Mosul area of northern Iraq, which is tectonically located in the Low Folded Zone characterized by the deposition of limestone and marly limestone of the Jeribe Formation during the Middle Miocene. Petrography has provided a diversity of fauna such as benthonic foraminifera (Miliolid, Peneroplis sp., Dendritina sp. and Borelis melo curdica) in addition to Red Algae and Mollusca. The Jeribe carbonates were affected by various diagenetic processes such as dolomitization, neomorphism, cementation, anhydritization, compaction and dissolution. Many microfacies have been identified, including lime mudestone, wackestone, packstone and Milioldal grainstone, with eight submicrofacies (Non-Fossiliferous lime mudstone, Benthonic lime mudstone, Fossiliferous wackestone, Red Algal wackestone, Milioldal packstone, Fossiliferous packstone, Green Algal packstone and Red Algal packstone). Depending on microfacies analysis, the Jeribe Formation was deposited in restricted and open marine environments within an interior platform setting.

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 prima guerra punica. ; The excavation in the park of Villa Belmonte (Monte Pellegrino, Palermo) has brought to light several warehouses, made with a "pseudo-frame" technique, probably with a straw roof, used for the storage of foodstuffs, given the large quantity of Punic-type amphorae found in situ, datable to around the middle of the third century BC. In addition, a section of road - about 3 m wide that proceeds in the direction of WNW- ESE, consisting of two layers of use - has been intercepted. We believe to have tracked down part of a strategic/military station used by the Carthaginian army during the crucial years of the First Punic War.

This dissertation examines Late Formative Period (200 BC-300 AD) communities of potting practice at the three settlements of Kala Uyuni, Kumi Kipa and Sonaji on the Taraco Peninsula, of the Lake Titicaca Basin, Bolivia. Ceramics play a central role in defining the social boundaries of prehistoric communities in the region. However our current narratives are stymied for the Late Formative Period, which precedes the appearance of the urban center of Tiwanaku (AD 400- 950). This is partly due to a reliance on ceramic design style. This study develops a practice-oriented approach to define Taraco Peninsula technological styles, refine the local ceramic chronology and evaluate the relationship between Late Formative communities and pottery. A "communities of practice" approach (Lave and Wenger 1991), which stresses the social entanglements between learning and identity, drives the analysis of the subtle changes in production sequences and their related consumption practices. Pottery production and consumption at Kala Uyuni, Kumi Kipa and Sonaji were analyzed through attribute analysis, petrography, x-ray fluorescence and x-ray diffraction. Shifts in learned bodily practice, such as surface finishing techniques, and a suite of new technological choices, including paste preparation, define both the transition to the Late Formative Period and internal sub-phases. These technological choices were likely linked to a larger symbolic landscape and embedded in a greater productive taskscape. The spatial context of production tools suggests that pottery was manufacture in all three settlements. A survey of the local hills found that potters likely used local clays, while petrography showed that tempers were added and may have been collected further afield. The similarity in operational sequences and paste recipes indicates that Taraco potters were a single learning community and part of their identities were likely constituted through their skillful potting practice. Consumption patterns changed slightly through the Middle and Late Formative, with an increased use of deep bowl forms. Large-scale political feasting, essential to the urban experience at Tiwanaku, was not a central social practice. Rather particular forms had multi-purpose functions, framing special events. This research contributes to social archaeologies of community, research on craft production and archaeological theories of practice.

[EN] This study focuses on the Late Cretaceous dolomitic units situated at the southern margin of the Central System in Spain. Dolomites were petrographically studied (transmited light, cathodoluminescence and scanning electron microscopy) and geochemically characterized (Mg/Ca ratio, ä13C, ä18O, 87Sr/86Sr) to interpret the diagenetic environment in which they precipitated and to infer the possible mechanisms for dolomitization. Our data suggest that units of the lower and middle part of the section (Caballar, Castrojimeno and Burgo de Osma Fms.), although deposited in different sedimentary environments, were simultaneously dolomitized during the initial stages of burial, via the refl ux of brines derived from the overlying Valle de Tabladillo Fm. This formation consists of interbedded evaporites and dolomicrites and/or collapsed breccias and was deposited in a coastal sabkha environment, where the unit was dolomitized during the initial stages of diagenesis. ; [ES] Este trabajo ha consistido en la caracterizacion petrografi ca y geoquimica de las unidades dolomiticas del Cretacico Superior que se encuentran en el borde Sur del Sistema Central, en la interpretacion del ambiente diagenetico de precipitacion de las dolomias y en la defi nicion del modelo de dolomitizacion para cada una de las unidades. El estudio petrografi co, realizado mediante microscopia convencional, catodoluminiscencia y microscopia electronica, y el estudio geoquimico elemental (relacion Mg/Ca) e isotopico (ƒÂ13C, ƒÂ18O y 87Sr/86Sr) de las dolomias sugieren que las unidades que se encuentran en la parte inferior y media de la serie (formaciones Caballar, Castrojimeno y Burgo de Osma), aunque se depositaron en ambientes sedimentarios distintos, se dolomitizaron a la vez, durante las primeras etapas del enterramiento, mediante el refl ujo de salmueras procedentes de la unidad suprayacente, la Fm. Valle de Tabladillo. La Fm. Valle de Tabladillo, por su parte, esta formada una alternancia de evaporitas y dolomias o bien por brechas de colapso y su dolomitizacion tuvo lugar durante las etapas mas tempranas de la diagenesis de acuerdo con el modelo de "gsabkha". ; Funds for this study were provided by a postdoctoral fellowship to the fi rst author by the Comunidad de Madrid and the European Union and by the Ministerio de Educación y Cultura of Spanish government (projects No. PB97-0298, BTE2001-026 and BTE2002-04453- C02-02). The authors would like to thank L. Wingate, G. Herrero, B. Moral, A. Fernández, and I. Sevillano for their technical support. We also thank Kyger C. Lohmann, Agustín Martín-Algarra and Alfonso Yébenes for their reviews, which have improved this paper. ; Peer reviewed

The carbonate ramp facies of the Late Albian-Early Cenomanian Mauddud Formation were studied in the Ratawi Oilfield, Basra Governorate, south of Iraq using integrated borehole data set that included, core and cutting samples in three drilled wells to analyze the petrography of the Mauddud Formation, two hundred and eighty-one (281) thin sections were prepared and examined for the three selected wells. The results show that the formation is composed of light grey dolomitized limestone and pseudo-oolitic creamy limestone with green to bluish shale. The petrographic observations results show four facies' associations in the Mauddud Formation. These include: Mid–Ramp environment which is represented by Argillaceous mudstone microfacies, Argillaceous wackestone microfacies and orbitolinid wackestone microfacies; the shallow open marine environment which is assimilated by foraminiferal wackestone microfacies and foraminiferal packstone microfacies; a restricted marine environment that represented by bioclastic fossiliferous wackestone microfacies and miliolid wackestone microfacies and Shoal environment is represented by bioclastic packstone microfacies, bioclastic grainstone microfacies, peloidal foraminiferal pack-grainstone microfacies, and peloidal packstone-grainstone microfacies with diverse skeletal grains. The porosity includes Vuggy, Interparticle, Intraparticle and Fracture porosity.

Mukdadiya Formation represents one of the formations that cover a huge area of Iraq. It contains several clastic deposits, such as sandstone, siltstone, and a noticeable amount of gravels. The gravels are considered as the hallmark to differentiate between Injana and Mukdadiya formations. Therefore, the current study focused on these facies to determine the petrography, paleontology , and origin of Mukdadiya deposits. The results of SEM-EDX and XRD analyses showed two types of gravels, namely the siliceous and lime gravels. The highest percentage of gravels belonged to the sedimentary origin (limestone). The elements of Si, Ca, and Fe represented the common elements that formed the studied gravels. The paleontological study displayed numerous fossils that are composed of these gravels, belonging to several groups, including foraminifera, radiolaria, dinoflagellata, echinoida, gastropoda, and calcisphera. Also, four microfacies were identified in the studied gravels. After comparison of all collected data with selected formations, the results confirmed that the origin of the derived gravels is from the Qulqula Formation, because of their content of radiolaria and the other characterizing fossils.

Compiled by Gary L. Baughman. ; The publication of this edition has been prompted by the significant increase in synthetic fuels activity since publication of the first edition in 1975. To reflect these recent advances, the second edition contains updated information, dramatically expanded sections, and several totally new sections. In particular, the oil shale section has been expanded to include Devonian-Mississippian black shales as well as Green River formation shale. The oil shale geology section has been extensively rewritten to be much more comprehensive. In addition, a new section on oil shale mining has been added, and discussions of the various retorting technologies have been expanded and updated. The second edition also describes in considerable detail existing in situ technology, which in recent years has been extensively studied through both government and industrial research programs. ; U.S. Oil Shale: Introduction -- Deposits -- Composition -- Physical Properties -- Thermal Properties -- Mining Methods -- Retorting Process -- Product -- By-Product -- and Waste Properties. U.S. Coal: Introduction -- Deposits -- Classification -- Petrography -- Composition -- Physical Properties -- Thermal Properties -- Coal Gasification -- Coal Liquefaction. Oil Sands: Composition -- Physical Properties -- Thermal Properties -- Products -- By-Products -- and Wastes -- Recovery Processes -- Commercial Ventures

The first economical unconventional play outside North America: context, history, and "coopetition" -- An exceptional tectonic setting along the Andean Continental Margin -- Statigraphic context: cyclostatigraphy, magnetostratigraphy, and seismic stratigraphy -- Relevant marine paleobiological markers of the Vaca Muerta formation -- Stuctural geology: tectonic history, macrostructures, regional fault map, fault systems, second-order structures, and impact of the inheritance -- Basin configuration during the Vaca Muerta times -- Sequence stratigraphy and the three-dimensional distribution of organic-rich units -- Sedimentology, depositional model, and implications for reservoir quality -- Seismic geomorphology, depositional elements, and clinoform sedimentary processes: impact on unconventional reservoir prediction -- Grain association, petrography, and lithofacies -- Organic geochemical patterns of the Vaca Muerta formation -- Reservoir properties: mineralogy, porosity, and fluid types -- Geomechanics: pressure, stress field, and hydraulic fractures -- Natural fractures: from core and outcrop observations to subsurface models -- Full development phase of the Loma Compana Block: black oil to gas and condensate windows -- De-risking the Sierras Blancas and Cruz de Lorena Blocks, black-oil window -- Pilot phase of the Aguada Federal Block, black-oil window -- Pilot phase of the Aguada Pichana Este Block, gas window -- "Factory mode" development of Fortín de Piedra Block, gas window -- Oil production from a sill complex within the Vaca Muerta formation.

A newly discovered prehistoric stela from Cañaveral de León (Huelva, Spain) is studied through a combination of scientific methods, including thin section petrography and lithological contextualisation, various state-of-the-art digital imaging techniques for the analysis of the engraved motifs (3D modelling and Reflectance Transformation Imaging), and detection of pigments on its surface (Principal Components Analysis, HSI-contrast stretch, ferric pigments index and algebraic operations between bands), as well as archaeological surveys aimed at establishing the landscape context the stela was part of. The results reveal this stela is analogous to a larger series of late prehistoric sculptures portraying personages with 'headdresses', largely concentrated in the Iberian south-west and often connected to Bronze Age settlements and burial sites. In addition, the Cañaveral de León stela is closely associated to an old pathway that has had a historical prominence in terms of long-distance mobility, connecting various regions of western Spain in a South-North direction. ; We also wish to acknowledge the professional support of the CSIC Interdisciplinary Thematic Platform Open Heritage: Research and Society (PTI-PAIS). This project was partly funded by the Andalusian Regional Government annual research grant to the Research Group ATLAS (HUM-694), of the University of Sevilla.

This article reviews published archaeological research that explores the potential of combined chemical and petrographic analyses to distinguish manufacturing methods of ceramics made From Nile river silt. The methodology was initially applied to distinguish the production methods of Egyptian and Nubian- style vessels found in New Kingdom and Napatan Period Egyptian colonial centers in Upper Nubia. Conducted in the context of ongoing excavations and surveys at the third cataract, ceramic characterization can be used to explore the dynamic role pottery production may have played in Egyptian efforts to integrate with or alter native Nubian culture. Results reveal that, despite overall similar geochemistry, x-ray fluorescence (XRF), instrumental neutron activation analysis (INAA), and petrography can distinguish Egyptian and Nubian-style ceramic traditions based on the relative degree of compositional homogeneity and subtle differences in paste recipes. This in turn indicates that cultural differences in craft production were sustained over time within the ethnically mixed communities of Upper Nubia. Based on these positive results, the methodology shows potential for addressing additional research questions in the Nile Valley, and a current research plan by the authors applies these same techniques to an evaluation of the role of ceramic craft centralization in the rise of the native Nubian Kerma state.

Intro -- Contents -- Preface -- Chapter 1 -- The Volturno Basin (Southern Italy): Insights into the Seismo-Stratigraphy and Structure of the Campania Plain (Southern Italy) -- Abstract -- Introduction -- Materials and Methods -- Regional Geologic Setting -- Data Acquisition and Processing -- Results -- Seismic Interpretation -- Stratigraphic Correlation of Deep Lithostratigraphic Data -- Calibrated Geological Section -- Conclusion -- References -- Chapter 2 -- Geoscience of the Built Environment: A Contribution for the Perspectives on the Anthropocene -- Abstract -- Introduction - Justification and Guide for This Chapter -- Setting the Stage -- Geological Materials in the Built Environment -- Geological Processes and Built Structures -- Built Environment as Training Ground on Geosciences -- Final Considerations -- Acknowledgments -- References -- Chapter 3 -- REE and Y Mineralogy of the Moldanubian Batholith (Central European Variscides) -- Abstract -- 1. Introduction -- 2. Geological Setting -- 3. Analytical Methods -- 4. Results and Discussion -- 4.1. Petrography -- 4.2. Geochemistry -- 4.3. REE and Y Mineralogy -- 4.3.1. Crystallization Sequences of Monazite, Xenotime and Allanite -- 4.3.2. Monazite Composition -- 4.3.3. Xenotime Composition -- 4.3.4. Allanite Composition -- Conclusion -- Acknowledgments -- References -- Chapter 4 -- Satellite Gravimetry ('Big Data'): A Powerful Tool for Regional Tectonic Examination and Reconstructions -- Abstract -- 1. Introduction -- 2. Satellite Derived Gravity Data -- 3. Gravity Data Examination: A Short Review of Methodologies -- 3.1. Entropy Computation -- 3.2. Multidimensional Self-Adapting Filtering -- 3.3. Method of Inverse Probabilities -- 3.4. Informational Approach -- 3.5. Multidimensional Statistical Analysis -- 3.6. 3D Inversion -- 3.7. Gradient Operator