Fossiliferous Limestone Research Articles

Stratigraphy and Facies Analysis of the Govanda Formation from Western Zagros, Kurdistan Region, Northeastern Iraq

Stratigraphy and Facies Analysis of the Govanda Formation from Western Zagros, Kurdistan Region, Northeastern Iraq

Reservoir characteristics and hydrocarbon accumulation of the glauconitic sandstone in the Tarapoa Block, Oriente Basin, Ecuador

Although Oriente basin has explored throughout the past fifty years, little is known about the reservoir quality and hydrocarbon accumulation of the Cretaceous Upper T glauconitic sandstones. Until recently, the Upper T has drawn attention due to the commercial oil discovery. Howerer, exploration of glauconitic sandstones is complicated and reservoir quality is difficult to evaluate based on logging and seismic data.The glauconitic sandstones developed in open marine environments, characterized by a framework of glauconite and quartz grains. Diagenesis includes compation, silica overgrowth, feldspars dissolution, iron carbonate cementation. Its porosity ranges 5–20% and less than 500 md permeability. The dominant pore type is intergranular, especially residual intergranular. Glauconitic sandstones have bimodal pore throat size distributions and complex pore geometries.The Upper T glauconitic sandstones are capped by a thin veneer of fossiliferous limestones and laminated to burrowed shales. These large-area matured source rocks close to the glauconitic sandstones are probably the source kitchen in the slope of Oriente Basin. The oil pools are very little relation to structure. A large area of continuous developed glauconitic sandstone reservoirs and adjacent source rocks form an excellent source–reservoir–cap assemblage. Differ from previous views of long-distance migration from the southwest Oriente Basin, we propose that volume flow and diffusive flow are the primary migration and accumulation mechanism for the Upper T reservoir in Tarapoa Block.

A FACIOLOGIA DO GRUPO PASSA DOIS NO RIO GRANDE DO SUL

The study of geological sections in the outcropping area of the Passa Dois Group in Rio Grande do Sul, complemented with the study of cores from drillings for coal, showed the relations in the State, which are related bellow. 1) The Passa Dois Group is constituted by the Irati and Estrada Nova Formations; the Rio do Rasto Formations is lacking. 2) The thickness of the group is about 100 m. 3) The contact with the subjacent formation is characterized by the occurrence of limestone concretions immersed in a grey silty shale, very similar to the Palermo Formation. 4) The Irati Formation has two facies. One characterized by the occurrence of two beds of pyrobituminous shale associated with fossiliferous limestone lenses. These two beds are intercalated with a grey silty shale with concoidal fracture, and with yellowish limestone concretions immersed in it. This facies, when present, occupies the lower part of the formation and was called Tiaraju facies. The second facies, partially synchronous with the first one, is constituted by grey silty shales with limestone concretions and West of Pantano Grande, is cut by oblique veins of silica. Toward the east it is predominantly siltic, showing cross-lamination. This facies ends the Irati deposition in the State and was called Valente facies. 5) The Estrada Nova Formation also has two lithologic facies, one being pellitic; the other, sandy, which, when present, occupies the top. The pellitic facies was called Caveiras facies and is characterized by the development of pink and red colours alternating with grey. The sandy facies, also reddish, is characterized by lenticular bodies of very fine sandstone, by occurrences of limestone lenses with irregular shapes, and also by large limestone concretions. This facies was called Armada facies. 6) The upper limit of the group was set on the contact of the above mentioned lithologies with a pink medium sanstone, with planar and channal cross stratifications, and with intraformational conglomerates.

RECORD OF KHURMALA FORMATION (LATE PALEOCENE – EARLY EOCENE) IN THE SULAIMANIAH GOVERNORATE, KURDISTAN REGION, NORTHEAST IRAQ

The present study focuses on the field, petrography and stratigraphic analyses of a thick and sparsely fossiliferous dolomitic limestone succession in the west, north, and northwest of Darbandikhan town from Sulaimaniah governorate. The succession thins toward northwest and east and located in the stratigraphic position of and Khurmala (or Sinjar) Formation (Late Paleocene – Early Eocene) between Kolosh and Gercus formations at the base and top respectively. The Khurmala Formation is a lagoonal crystallized limestone, dolomite with interbeds of different clastic rocks. It also contains an occasional occurrence of gypsum and rare gastropods, miliolids, and algae in some beds. Previous studies found the formation and described in Duhok, Kirkuk and Erbil Governorates while in Sulaimani area it not proved until now. The present article studied four different sections of succession (previously and indicated as Sinjar Formation) and correlated them stratigraphically with each other and with Khurmala Formation in its type section in the well K-114. The study showed that these sections belong to Khurmala Formation. The sections reveal many evidences and signs of the occurrence of Khurmala Formation in between Kolosh and Gercus formations. These signs are the occurrence of 160 m of dolomitic limestone (80%) with beds of sparsely fossiliferous limestone (18%) and conglomeratic limestone (2%) in Zawali section on Shameran Mountain. The fossiliferous intervals contain lagoonal sparse and small miliolids, gastropods, pelecypods green and red algae. The formation laterally changes to Kolosh (in Mirade section) or partly to Sinjar Formation (in Dara Rash section). In the Mirade section, neither Sinjar nor Khurmala Formation is deposited and yellow marly limestone, sandstone and few beds of conglomerate occupy their stratigraphic position.

Early Mesozoic sedimentary‒tectonic evolution of the Central-East Iranian Microcontinent: Evidence from a provenance study of the Nakhlak Group

In Central Iran, the mixed siliciclastic‒carbonate Nakhlak Group of Triassic age is commonly seen to have a Cimmerian affinity, although it shows considerable resemblances with the Triassic Aghdarband Group in far northeastern Iran, east of Kopeh-Dagh area, with Eurasian affinity. The Nakhlak Group is composed of the Alam (Late Olenekian‒Anisian), Baqoroq (Late Anisian‒?Early Ladinian), and Ashin (Ladinian‒?Early Carnian) formations consisting mainly of volcanoclastic sandstone and shale and fossiliferous limestone. The Baqoroq Formation contains also metamorphic detritus. Sandstone petrofacies reflect the detrital evolution from active volcanism to growing orogen and again active volcanism. Textural and modal analyses of volcanic lithic fragments from the Alam Formation reflect the eruption style and magma composition of a felsic to intermediate syn-sedimentary arc activity. The detrital modes of the Baqoroq Formation sediments suggest a recycled orogenic source followed by arc activity in a remnant fore-arc basin. The sandstone samples from the Ashin Formation demonstrate a continuity of felsic to intermediate arc activity. Major and trace element concentrations of the Nakhlak Group clastic samples support sediment supply from first-cycle material and felsic magmatic arc input. The enrichment in LREE, the negative Eu anomalies, and the flat HREE patterns indicate origination from the old upper continental crust and young arc material. The chemical index of alteration (CIA ∼51–70 for sandstone and 64–76 for shale samples) indicates medium degrees of chemical weathering at the source. Petrographical and geochemical evidence together with facies analysis constructed the following depositional conditions for the Nakhlak Group sediments: In the Olenekian, a fore-arc shallow to deep marine depositional basin developed that later was filled by recycled and arc-related detritus and changed into a continental basin in the Anisian. Ladinian extension let to a deepening of the basin. With respect to the similarities between the Nakhlak and Aghdarband (NE Iran) groups and unusual present-day position of the Nakhlak Group with no stratigraphic connection to the surrounding area, the development of first a fore-arc basin and later change into a back-arc depositional basin in close relation with the Aghdarband basin at the southern Eurasian active margin in the Triassic are here proposed. Understanding the basin development recorded in the Nakhlak Group provides constraints on the closure history of Palaeotethys and of the tectonic evolution of early Mesozoic basins at the southern Eurasian margin before the Cimmerian Orogeny.

A NEW CONSIDERATION ABOUT THE ALMOPIA-PAIKON BOUNDARY BASED ON THE GEOLOGICAL MAPPING IN THE AREA OF NEROSTOMA-LAKKA (CENTRAL MACEDONIA, GREECE)

Geological mapping along the boundary of Almopia and Paikon zone in the 'Nerostoma' region, NNW of Lakka village defines mafic volcanogenic rocL·, meta-pelites and radiolarites, thick-bedded to massive micritic limestones and flysch meta-sediments that dip mainly towards SW. Middle-Late Cretaceous fossiliferous limestones overlie unconformably the flysch meta-sediments and are characterised only by a primary foliation SO that dips at shallow angles to the NNW-N. Secondary foliations SI (sub-parallel to SO) and S2 are observed in the meta-clastic rocks. A Dl event caused Fl and progressively F2 folds to which S2 is the axial plane schistosity dipping to SW. This event which has not affected the fossiliferous limestones is related to an oblique convergence or inclined transpression during the Late Jurassic-Early Cretaceous. A D2 event dated in Early Tertiary caused an intense NE-thrusting and S-C cataclastic fabric defining top-to-the NE sense-of-shear. At many parts, the unconformity contact between the fossiliferous limestones and the underlying flysch is obliterated by this thrusting event. As a result, the boundary between Almopia and Paikon zones as paleo-geographically defined in this area seems to be meaningless for the Jurassic-Cretaceous times.

Origin of the mud volcanoes in the south east Caspian Basin, Iran

Abstract: The Gorgan Plain (SE Caspian Basin) contains several mud volcanoes. The Gharenyaregh, Neftlijeh, Sofikam and Inche mud volcanoes are active and erupting mud and gas. Mud volcanoes occur in an area characterized by seismic activity. The Sofikam mud volcano consists of five craters that define a NE-directed (60°) linear arrangement, which coincides with a subsurface anticline of the western Kopeh Dagh fold-thrust belt. The main craters of the Inche and Neftlijeh mud volcanoes are submerged. The Gharenyaregh mud volcano is an active mud volcano whose crater is nearly 500 m in diameter. Clasts collected from the Gharenyaregh mud volcano (GMV) mainly consist of glauconite-sandstone, limestone (±ammonite), marl, and fossiliferous limestone (lumachelle) with bioclasts ranging in size from millimeters to centimeters. X-ray diffraction (XRD) analyses revealed quartz, calcite, feldspar, chlorite, illite, glauconite, halite and gypsum minerals in the clasts and soft materials of the GMV. The clasts are comparable with rock fragments originating from the underlying Kopeh Dagh related formations and the uppermost Caspian basin sediments. Regression of the South Caspian Sea shoreline from east to west (across modern-day Golestan province), seismic activity and buried folds indicate that the south east Caspian basin mud volcanoes are located in a tectonically active area and generated from deeper parts of the Gorgan Plain. Some large, conical hills with a record of historical human activity, located between the Kopeh Dagh zone and the South Caspian Sea, seem to be inactive mud volcanoes.

The interaction of recovery and environmental conditions: An analysis of the outer shelf edge of western North America during the early Triassic

Biotic recovery from the Permian-Triassic mass extinction was complex and uneven, with prior studies typically revealing a long, drawn-out recovery that was either delayed for some interval, or was subdued and stepwise in nature. Examples of rapid recovery at the outcrop scale cloud this narrative and point to the importance of environmental stresses in determining the timing and shape of recovery. The Union Wash Formation at the Darwin locality (east-central California) contains at least 3 recovery intervals that terminate with the onset of deleterious conditions and therefore offers a means to examine the relationship between environmental stress and recovery. The first recovery is manifested as bioturbated (ii = 5–6), shallow marine micritic limestones that contain small diameter (2–4 mm) Thalassinoides burrows that form complex networks. This interval is overlain by 650.5 m of laminated mudstone that signal deleterious environmental conditions. The second recovery interval begins directly above seafloor precipitate-bearing micritic limestones that make up the lowermost 130 m of the upper member of the Union Wash Formation and is marked by the occurrence of a 3 m-thick interval containing sphinctozoan sponges, an intervening ~1 m-thick laminated (ii = 1) micritic limestone, and an overlying, 5 m-thick bivalve-rich and bioturbated calcareous siltstone (ii = 4–5) that contains Chrondrites trace fossils. This interval is overlain by 18 m of laminated green shale (ii = 1) that signifies another incursion of anoxic waters. The third recovery interval is represented by a 30 m-thick unit that includes beds of micritic limestone, fossiliferous limestone containing transported fossil grains (including bivalves, microgastropods, sphinctozoan sponges, microgastropods, flat clams, and terebratulid brachiopods), flat pebble conglomerate and vermicular limestone. The results of this study, therefore, point to an uneven recovery within the Union Wash Formation, in which an initially robust recovery in the lower member deteriorated across the remainder of the study section. Areas exposed to persistent environmental stress, therefore, demonstrate protracted and complex recoveries. Study localities located within the habitable zone instead exhibit accelerated recoveries during the post-extinction interval and are indicative of an environmental bias in the form of persistent favorable conditions. The most accurate measures of post – extinction recovery, therefore, are those that examine biotic trends over a broad geographic area, and, as a result, incorporate the role of environmental stress in determining when and how life recovered from the Permian – Triassic mass extinction.

An investigation into preserving spatially-distinct pore systems in multi-component rocks using a fossiliferous limestone example

Limestones containing abundant disc-shaped fossil Nummulites can form significant hydrocarbon reservoirs but they have a distinctly heterogeneous distribution of pore shapes, sizes and connectivities, which make it particularly difficult to calculate petrophysical properties and consequent flow outcomes. The severity of the problem rests on the wide length-scale range from the millimetre scale of the fossil's pore space to the micron scale of rock matrix pores. This work develops a technique to incorporate multi-scale void systems into a pore network, which is used to calculate the petrophysical properties for subsequent flow simulations at different stages in the limestone's petrophysical evolution. While rock pore size, shape and connectivity can be determined, with varying levels of fidelity, using techniques such as X-ray computed tomography (CT) or scanning electron microscopy (SEM), this work represents a more challenging class where the rock of interest is insufficiently sampled or, as here, has been overprinted by extensive chemical diagenesis. The main challenge is integrating multi-scale void structures derived from both SEM and CT images, into a single model or a pore-scale network while still honouring the nature of the connections across these length scales. Pore network flow simulations are used to illustrate the technique but of equal importance, to demonstrate how supportable earlier-stage petrophysical property distributions can be used to assess the viability of several potential geological event sequences. The results of our flow simulations on generated models highlight the requirement for correct determination of the dominant pore scales (one plus of nm, μm, mm, cm), the spatial correlation and the cross-scale connections.

Automatic Identification of Calcareous Lithologies Using Support Vector Machines, Borehole Logs and Fractal Dimension of Borehole Electrical Imaging

In this research algorithms of support vector machine (SVM) and a logic function were applied to identify automatically sections of carbonate rocks in wells located in the former Barco Concession, Catatumbo Basin - Colombia. During training stages the SVMs use neutron, photoelectric factor and gamma ray logs as input; also mean and variance of resistivity acquired for image tool and fractal dimension of resistive images. The first SVM employs in the training stage intervals manually interpreted of fossiliferous limestone, performed by a specialized geologist integrating information of core-logs correlation of a pilot well; afterwards, in classification stages, this SVM automatically recognizes intervals with fossiliferous limestone only using logs data of any well of the field. The second SVM was also trained with nuclear logs, resistivity and fractal dimension, but in this case, with information of intervals composed of calcareous shales interbedded with limestone, recognizing automatically these rock associations during classification stage without interpretations of a geologist as input data. Additionally, a logic function was applied to intervals with photoelectric factor ≥ 4 and all sections not classified by the SVMs were grouped as laminated calcareous rocks. The SVMs and logic function show accuracy of 98.76 %, 94.02 % and 94.60 % respectively in six evaluated wells and might be applied to other wells in the field that have the same dataset. This methodology is highly dependent of the data quality and all intervals affected by bad borehole condition have to be removed prior its application in order to avoid wrong interpretations. Finally, the whole model has to be recalibrated to be applied in other fields of the basin.

Late Smithian microbial deposits and their lateral marine fossiliferous limestones (Early Triassic, Hurricane Cliffs, Utah, USA)

Recurrent microbialite proliferations during the Early Triassic are usually explained by ecological relaxation and abnormal oceanic conditions. Most Early Triassic microbialites are described as single or multiple lithological units without detailed ecological information about lateral and coeval fossiliferous deposits. Exposed rocks along Workman Wash in the Hurricane Cliffs (southwestern Utah, USA) provide an opportunity to reconstruct the spatial relationships of late Smithian microbialites with adjacent and contemporaneous fossiliferous sediments. Microbialites deposited in an intertidal to subtidal interior platform are intercalated between inner tidal flat dolosiltstones and subtidal bioturbated fossiliferous limestones. Facies variations along these fossiliferous deposits and microbialites can be traced laterally over a few hundreds of meters. Preserved organisms reflect a moderately diversified assemblage, contemporaneous to the microbialite formation. The presence of such a fauna, including some stenohaline organisms (echinoderms), indicates that the development of these late Smithian microbial deposits occurred in normal-marine waters as a simple facies belt subject to relative sea-level changes. Based on this case study, the proliferation of microbialites cannot be considered as direct evidence for presumed harsh environmental conditions.

Marmora Lusitana en la Bética romana

Hacia finales de los años 1970, en los inicios de la línea de investigación sobre marmora -entendidos como rocas ornamentales en un sentido amplio- de interés histórico arqueológico en la Península Ibérica, son varios los distritos de canteras portuguesas que se encuentran incluidos en los listados de áreas fuente explotados en época romana. A lo largo de las últimas décadas y con un impulso renovado en años recientes, coincidiendo con la aplicación más frecuente de métodos de análisis arqueométricos que permiten identificar con mayores garantías las procedencias de los materiales arqueológicos analizados, se han ido conociendo diversos aspectos de la distribución y uso de los marmora Lusitana en diferentes contextos de la geografía hispana. La bibliografía de referencia de las últimas décadas ha fomentado la impresión de la presencia habitual de los marmora Lusitana en la Bética y la difusión de una serie de propuestas sobre los mecanismos de distribución y los patrones de uso de estos materiales en nuestra zona de estudio. La revisión detallada de la base empírica disponible obliga, sin embargo, a destacar el número muy bajo de identificaciones individuales documentadas y la imprecisión de las propuestas previas de reconstrucción histórica de los patrones de distribución y uso de los marmora Lusitana en la provincia Baetica. La revisión y los nuevos análisis de los materiales marmóreos de procedencia lusitana documentados en la actual Andalucía Occidental permiten observar la presencia de mármol del Anticlinal de Estremoz (Distrito de Évora), de caliza fosilífera de Sintra (Distrito de Lisboa) y, en menor medida, de mármoles de Trigaches (Distrito de Beja) y Viana do Alentejo (Distrito de Évora). El análisis de las informaciones arqueológicas asociadas a estos materiales permite profundizar en la reconstrucción histórica de los circuitos comerciales entre la Lusitania y la Bética occidental romanas. Los progresos en la identificación analítica de los diferentes marmora portugueses permiten, de manera especial, confirmar la importancia suprarregional de estos materiales, pero también subrayar las necesidades de análisis futuros que planteen sus mecanismos de distribución y sus patrones de uso, que ilustramos en este trabajo mediante una serie de casos de estudio arqueométricos recientes.

Combined Use of Remote Sensing Data, Mineralogical Analyses, Microstructure Studies and Geographic Information System for Geological Mapping of Antiparos Island (Greece)

This study presents the combined use of field mapping, remote sensing data analysis, mineralogy, spectroscopy and GIS techniques for the geological mapping of Antiparos Island. Antiparos is part of the Cyclades Blueschist Belt located in central Aegean, where gneisses, schists and Pliocene volcanic rocks occurred. During the extended field work, a number of volcanic rock samples were collected from the southern part of Antiparos. The sampling strategy was to collect samples from the primary as well as the altered rocks in specific areas in which they were previously located from the remote sensing data processing. In this study, high resolution satellite images have been carried out in order to detect, allocate and separate the different geological formations. Furthermore, the existing geological map was georeferenced and all the tectonic lines and boundaries were digitized. All these features were implemented in a Mobile Mapper CE GPS using Arcpad GIS and checked in situ. The collected samples were analyzed in the laboratory using various techniques including XRD, Petrographic Microscopy and SEM. The qualitative mineralogical analyses were conducted by using XRD. The study was supplemented by the petrographic observations providing a detailed characterization of rock textures. In addition, SEM study and SEM-EDS analyses of the samples were emphasized on the genetic relations of the minerals. The laboratory results revealed that specific corrections should be made in the previous geological map of Antiparos concerning the volcanic rocks, especially at the southern part of the island. A significant conclusion is that the rock described as volcanic in the previous map proved to be a fossiliferous limestone which includes micritic matrix of calcite with an insignificant amount of fossils. All the analogical and digital data and the results of the petrographic analysis were imported in a geodatabase specially designed for geological data. After the necessary topological control and corrections, the data were unified and processed in order to create the final layout at 1/25.000 scale.

Microfacies analysis and diagenetic fabric of the Lockhart Limestone exposed near Taxila, Margalla Hill Range, Punjab, Pakistan

The microfacies analysis and diagenetic fabric of the Lockhart Limestone are studied in an outcrop section exposed in the Margalla Hill ranges. The Lockhart Limestone is predominantly composed of medium to thick bedded, nodular and occasionally brecciated, highly fossiliferous limestone with thin interbeds of marl and shale. On the basis of detailed petrographic investigations, four microfacies have been identified including bioclastic packstone, wackestone (siliciclastic bioclastic rich sub-microfacies), wackestone-packstone, and mud-wackestone. Based on the microfacies analysis, the Lockhart Limestone is interpreted to have been deposited in the fore-shoal mid-ramp, mid-ramp, and outer ramp depositional environments. The Paleocene age has been assigned to the Lockhart Limestone based on age diagnostic foraminifera, i.e., Miscellanea, Lockhartia, and Ranikothalia. The diagenetic fabric of the Lockhart Limestone is characterized by several diagenetic features such as micritization, neomorphism (aragonite to calcite transformation and development of microspar), compaction, pressure dissolution (microstylolites), and cementation (calcite-filled microfractures). Such diagenetic features are developed in marine, meteoric, and burial diagenetic settings. The Paleocene Lockhart Limestone of Pakistan shows analogous features to that of the Paleocene Zongpu Formation (Member-3) of the Gamba-Tingri Basin of southern Tibet based on the outcrop features, microscopic fabric, and depositional environment.

Impacts of fossil anisotropy on the electric and permeability anisotropy of highly fossiliferous limestone: a case study

The Middle Eocene Lutetian Samalut formation is among the best examples of anisotropic fossiliferous rocks in Egypt, where the effect of the anisotropic Nummulite Gizehensis fossils on the petrophysical behavior can be traced. The Samalut formation has been sampled and studied at Wadi Feiran in SW Sinai. Petrographically, it is composed of two microfacies; Nummulitic packstone and Fusulinid mudstone. Tight cementation by micro to pseudosparite, aggrading neomorphism and compaction with increasing load pressure are the most important porosity-reducing factors. The anisotropy of the fossil content (λF), due to shape and orientation, and its effect on the petrophysical properties were assigned by measuring the lengths of the longest and shortest axes. Petrophysically, both microfacies are characterized by low porosity values (1.47 ≤ $${\emptyset _{{\text{He}}}}$$ ≤ 5.29%). The formation resistivity factor (F) and permeability (k) were measured in the horizontal and vertical directions (parallel and perpendicular to the bedding plane, respectively). The studied samples are characterized by high to very high formation resistivity factor (190 ≤ F ≤ 8938) and relatively very low permeability (0.012 ≤ k ≤ 0.110 md). The studied samples are characterized by fair to medium electric anisotropy ‘λE’, which is attributed to a relatively medium to fair degree of electric foliation. It has been shown that, the fossil shape anisotropy and orientation ‘λF’ (1.5 ≤ λF ≤ 3.5) is the main contributor for the electric and permeability anisotropy that corrected for the same porosity value (1.61 ≤ λEC ≤ 2.25 and 1.03 ≤ λkC ≤ 2.04; respectively). Foliation of the studied microfacies has been contributed to the orientation of the fossil remains parallel to the bedding plane. The anisotropy degree is relatively greater for the Nummulitic packstone microfacies than that of the Fusulinid mudstone. The present study refers to the possible anisotropic effect of fossil content (due to shape and orientation) on the petrophysical properties of the studied rocks which may be extended to the anisotropy of reservoir rocks on the bedding scale.

Evaluation of Accelerated Ageing Tests for Metallic and Non-Metallic Graffiti Paints Applied to Stone

Graffiti are increasingly observed on urban and peri-urban buildings and their removal requires a huge financial outlay by local governments and agencies. Graffiti are not usually removed immediately, but rather over the passage of time, viz. months or even years. In this study, which forms part of a wider research project on graffiti removal, different methods (gravimetric analysis, examination of digital images, colour and infrared measurements) were used to evaluate the performance of accelerated ageing tests (involving exposure to humidity, freeze-thawing cycles and NaCl and Na2SO4 salts) for graffiti painted on stone. Silver (metallic) and black (non-metallic) graffiti spray paints were applied to two types of igneous rock (granite and rhyolitic ignimbrite) and one sedimentary rock (fossiliferous limestone, i.e., biocalcarenite). The metallic and non-metallic graffiti spray paints acted differently on the stone surfaces, both chemically and physically. Older graffiti were found to be more vulnerable to weathering agents. The ageing test with NaCl and particularly Na2SO4, both applied to granite, proved the most severe on the paints, yielding more detrimental and faster artificial ageing of the type of material under study.

Ground-based hyperspectral imaging and terrestrial laser scanning for fracture characterization in the Mississippian Boone Formation

Petroleum geoscientists have been using cores and well logs to study source rocks and reservoirs, however, the inherent discontinuous nature of these data cannot account for horizontal heterogeneities. Modern exploitation requires better understanding of important source rocks and reservoirs at outcrop scale. Remote sensing of outcrops is becoming a first order tool for reservoir analog studies including horizontal heterogeneities. This work used ground-based hyperspectral imaging, terrestrial laser scanning (TLS), and high-resolution photography to study a roadcut of the Boone Formation at Bella Vista, northwest Arkansas, and developed an outcrop model for reservoir analog analyses.The petroliferous Boone Formation consists of fossiliferous limestones interbedded with chert of early Mississippian age. We used remote sensing techniques to identify rock types and to collect 3D geometrical data. Mixture tuned matched filtering classification of hyperspectral data show that the outcrop is mostly limestones with interbedded chert nodules. 1315 fractures were classified according to their strata-bounding relationships, among these, larger fractures are dominantly striking in ENE – WSW directions. Fracture extraction data show that chert holds more fractures than limestones, and both vertical and horizontal heterogeneities exist in chert nodule distribution.Utilizing ground-based remote sensing, we have assembled a virtual outcrop model to extract mineral composition as well as fracture data from the model. We inferred anisotropy in vertical fracture permeability based on the dominancy of fracture orientations, the preferential distribution of fractures and distribution of chert nodules. These data are beneficial in reservoir analogs to study rock mechanics and fluid flow, and to improve well performances.

Eoalosa janvieri gen. et sp. nov., a new clupeid fish (Teleostei, Clupeiformes) from the Eocene of Monte Bolca, Italy

Fishes of the family Clupeidae are extremely abundant in the Eocene fossiliferous limestone of Monte Bolca representing the most common group from this celebrated locality. A new clupeid from the Pesciara site, Eoalosa janvieri gen. et sp. nov., is described. The new taxon exhibits a unique combination of characters supporting its recognition as a new genus and species of clupeid fish that is tentatively placed in the subfamily Alosinae. The description of this new taxon improves our knowledge of the diversity of clupeoid fishes in the Eocene of Monte Bolca.

Urban Geodiversity and Decorative Arts: the Curious Case of the “Rudist Tiles” of Lisbon (Portugal)

One key element defining the appearance of Lisbon is the whitish Cretaceous fossiliferous limestone locally known as “lios.” The lios is abundantly used as ornamental stone in Lisbon’s monuments and buildings. Ceramic tiles are also paramount in creating Lisbon’s character. Their ubiquitous presence, their colourful patterns and even the unique way they reflect sunlight make them inextricable from the city’s ambiance. In nineteenth century tiles, the urge to emulate lios—a noble and expensive building material—in building facades led to the use of the trompe l’oeil technique to mimic the appearance of the stone. The representation of the fossiliferous lios pattern is so realistic that Radiolitid and Caprinid rudists may easily be identified. At present, “rudist tiles” are not recognized as such by decorative arts experts. These tile panels are commonly seen as lesser productions depicting indistinct “marbled” patterns and often ignored or even discarded. This novel interpretation of rudist tiles leads to the clear recognition of the lios—a typical element of local geodiversity—depicted in them, thus revealing their uniqueness and close connection with the geodiversity and the cultural ambiance of Lisbon. Hopefully, this will boost the geoawareness of the public and art experts alike, making the need for the geoconservation of the lios and its palaeontological record and the preservation of these tiles as cultural heritage all the more obvious. This example of the influence of geodiversity in the creation of artistic concepts and representations and, consequently, in the shaping of the cultural landscape of Lisbon is all the more important now that the application of Portuguese tiles for inclusion on the UNESCO World Heritage List is being prepared.

High-level and long-term noise effect on soft rock building materials

In recent years, due to an increase in the number of tourists and music concerts in historical areas and a rise in the noise level caused by transport in these regions, an increase in noise-induced damage has been seen in historic structures. In the literature, few studies have examined the impact of sound sources on old buildings. In this study, two types of ignimbrite from the Cappadocia region, fossiliferous limestone used in historical Ottoman buildings, mudstone from the Kula Geopark area, and sandstone used in historic buildings in Erzurum were tested at different sound levels to determine the effect of noise on the rock samples. A new laboratory test setup was developed for noise-effect testing. The rock samples were placed in the sound-test cabinet and exposed to sound levels of 80–130 dB at 1–1200 min duration. Changes in the sonic velocity, porosity, water absorption by weight, and uniaxial compressive strengths of the samples were measured, as well as the deformation caused by the sound waves on the surface of the samples. At 80 dB, the surface of the mudstone samples began to disperse. Above 120 dB, small cracks occurred on the surfaces of all the samples.