Search results for "limestone"

Petrography and decay of a marly limestone in the cloister of a medieval cathedral in Sicily

2004

This paper deals with a significant process of decohesion of a marly limestone, taking place in the cloister of the medieval Cathedral of Cefalu, a pleasant town on the northern coast of Sicily. After desalination with deionised water and consolidation with ethyl silicate, the decay of the stone became faster. The aim of our study is to characterise the stony material and investigate the observed decay phenomena. The stone, that is a poor building material indeed, is characterised by means of petrographical, chemical and physical analyses on samples taken from the monument. Furthermore, experimental tests are performed in the laboratory in order to highlight the causes of incompatibility be…

Land Snail Fauna of “Porţile de Fier” (“Iron Gates”) Nature Park (Banat, Romania)

2014

Abstract The paper presents an analysis of terrestrial mollusc fauna of the “Iron Gates” Nature Park. Various types of habitats (e.g. forests, rocks, riparian areas) and substrates (e.g. limestone, conglomerate, crystalline schist) were analyzed. A total of 45 species of terrestrial gastropods were identified in 17 sampling points, four of which are mentioned for the first time in the area. Six other species cited in the literature were not found. Limestone substrate allows the development of large populations of terrestrial gastropods, but the specific diversity is larger when it is associated with a forest habitat. The current legal and illegal exploitation of limestone threatens the moll…

Aportaciones hidrogeológicas al estudio arqueológico de los orígenes de la Edad del Bronce de La Mancha: la cueva monumentalizada de Castillejo del B…

2014

Estudios recientes indican que las motillas, asentamientos de la Edad del Bronce de La Mancha, pudieron ser las más antiguas captaciones de agua subterránea en la Península Ibérica. Pero ¿por qué no existen motillas en el Campo de Montiel, territorio ubicado tradicionalmente en esta área cultural? En Castillejo del Bonete, sitio arqueológico situado en esa comarca, existe una cueva que fue utilizada y sellada durante la Prehistoria Reciente. Se presenta ahora la primera investigación paleohidrogeológica interdisciplinar en La Mancha, que ha analizado manantiales y niveles de agua subterránea del acuífero de Campo de Montiel, así como el interior de la sima de Castillejo del Bonete. Las conc…

Dissolution‐corrosion measurements with limestone and gypsum tablets in active sulphuric acid caves of southern Italy

2022

Dissolution‐corrosion (DC) represents an important factor for speleogenesis, and can be measured monitoring weight variation over time of carbonate and gypsum tablets exposed in underground environments. The oxidation of H2S produces H2SO4, which in carbonate host rock induces the surface of carbonate tablets to be rapidly corroded by sulphuric acid, whereby CaCO3 is replaced by CaSO4∙2H2O, producing a significant weight gain. We describe preliminary results of DC monitoring in four still‐active SAS systems, including Ninfe Cave and Terme Sibarite (Calabria), Fetida Cave (Apulia), and Acqua Fitusa Spring Cave (Sicily). The tablets have been set inside the caves, in three different condition…

Measure of a limestone weathering degree using Laser Scanner.

2013

The weathering degree of the building materials and natural stones is generally quantified as the decrement of some mechanical features that can be measured experimentally by means of compressive tests or point load tests in the laboratory or Schmidt hammer tests carried out in situ. Such destructive or damaging tests are unacceptable in case of cultural heritage since even small amounts of damage must be avoided. This work shows a correlation between Schmidt hammer rebound values and the reflectivity that is detected by means of terrestrial scanner laser; therefore it allows assessing the weathering degree of buildings or stones in situ. The results demonstrate that such an investigation c…

Facies Architecture and Evolution of a Cretaceous, Tectonically-Controlled, Carbonate Slope from Western Sicily (Italy)

2018

The stratigraphic architecture of a Cretaceous carbonate slope from north western Sicily (Italy) has been reconstructed on the basis of detailed field sections. The wire cut walls of a number of quarries that extract the Cretaceous limestones as ornamental stones allowed the mapping of the stratal architecture and lithologies at various scales. The vertical and lateral facies relationships in this about 1000 m thick depositional system account for a complex sedimentary dynamics along a carbonate platform escarpment that was strongly influenced by syn-sedimentary transtensional tectonics associated to magmatism. Although the original relationships with the carbonate platform were obscured by…

Investigation of mass graves in the Churchyard of St. Gertrude’s, Riga, Latvia

2011

Formation mechanisms of Neptunian dikes in the Jurassic carbonates of Monte Maranfusa (western Sicily)

2013

Younger sediment infilling open fissures exposed on the sea floor are defined as neptunian dikes. These are peculiar features of carbonate platform successions deposited along the plate margins bounding the western Tethys during the Late Triassic time. During middle-Early Jurassic, a large part of these carbonate platforms were drowned, and became submerged plateaux covered by pelagic sediments during Jurassic (“Rosso Ammonitico”) and Cretaceous times (“Scaglia”). In western Sicily, several Neptunian dikes crop out (Monte Kumeta, Rocca Busambra, Monte Maranfusa, Monte Magaggiaro, etc.). They cut across mainly the carbonate sediments of the Inici Formation and in some cases the pelagic limes…

Multitechnique diagnostic analysis and 3D surveying prior to the restoration of St. Michael defeating Evil painting by Mattia Preti

2021

In this study, a multimethodological analysis involving optical and physical/chemical diagnostic techniques and 3D photogrammetric survey was successfully applied, for the first time, on the large oil on canvas St. Michael defeating Evil painting by Mattia Preti, located inside the Church of the Immaculate Conception of Sarria (Floriana) in Malta. Pigmenting agents, binder media, and raw materials were first characterized, both at elemental and molecular scales, through X-ray fluorescence spectroscopy (XRF), optical stereo microscopy (SM), scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infrared spectroscopy (FT-IR), and gas chroma…

Quarry limestone dust as fine aggregate for concrete

2018

In quarrying activities, rock is extracted and transformed into aggregate of various sizes for civil engineering applications. In this process waste fine aggregates (dust waste) are generated. The disposal of this type of waste is a further cost in the extraction process, but also a possible cause of environmental pollution (e.g. leaching into water reserves, atmospheric pollution as a result of small particles causing respiratory diseases or deposited on plants disrupting photosynthesis, affecting aquatic habitats, etc.). A strategy for the effective recycling of quarry dust does not only reduce waste generation and disposal, but also addresses protection of the environment. The Italian qu…