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Instability determinants on the railroad Zagreb–Rijeka, Croatia
Published in Jan Rybář, Josef Stemberk, Peter Wagner, Landslides, 2018
D. Krajnović, Ž. Miklin, S. Kasapović
Along with the limestones it is the dolomitic rocks which are also found as intercalations in the wider region. The dolomite is of the late-diagenetic type with an intermediate to coarse-grained structure and a mosaic type of texture. Within the dolomitic complex rare irregular masses of limestone occur at places. The dolomitization processes have caused an appearance of layering in the bedrock. The dolomite is weathered on the surface and covered by a soil cover, which can be several meters thick. The dolomitization processes have destroyed all the primary limestone structures. In some lenses of limestone algal-foramenifaral mudstone and wackestone structures can be observed.
An approach to mitigate effects of colour variation, specularity and pores on microtexture analysis of aggregates
Published in International Journal of Pavement Engineering, 2020
Abolfazl Ravanshad, Sanghyun Chun, Reynaldo Roque, George Lopp
Images were obtained by scanning aggregate particles for virgin and MD-polished conditions with different illuminations. Figure 3 illustrates the results matrix, which was produced to take several factors into account. The first factor considered was the effect of colour variation on TI. All granites and siliceous wackestone, and one limestone (HN717) showed highly non-uniform colour pattern. However, all other limestones were uniform in colour. The second factor was the type of analysis either existing AIMS approach using a single image or new PS-ICA approach using multiple images. Lastly, the third factor was the light intensity to mitigate specularity effect on TI. All limestones, which may not exhibit specularity effects, were scanned at default light intensity whereas granites and siliceous wackestone, which may exhibit relatively greater specularity effects, were evaluated at both default and modified (reduced) light intensities.
Detection and classification of internal defects in limestone blocks based on a deconvolution technique with SI-PLCA applied to GPR signals
Published in Research in Nondestructive Evaluation, 2019
Maria Violeta Montiel-Zafra, F. Canadas-Quesada, P. Vera-Candeas, N. Ruiz-Reyes, J. Rey Arrans, J. Martínez López
Ground-Penetrating Radar (GPR) has been widely used to analyze quarries, usually by using portable equipment that can be used to quickly evaluate a block directly at the quarry. Sigurdsson [10] performed lithographic characterization studies in limestone quarries. Sigurdsson and Overgaard [11] studied limestone using GPR (using a 100 MHz antenna), which allowed them to differentiate zones with textural variations (bryozoan limestone, coral limestone, and wackestone). Grandjean and Gourry [2] and Kadioglu [12] used this technique to detect fractures in marble quarries in Greece and Turkey, respectively. Porsanic et al. [4] used GPR in granite quarries in Brazil. Recently, Rey et al. [5] used GPR techniques at a marble quarry in Macael (Almería, Spain). This study shows that GPR is able to differentiate marble units from mica schists, making GPR a suitable tool for evaluating the reserves in a quarry.
Subaerial disconformities, microkarst and paleosols in Ordovician limestones at Bowan Park and Cliefden Caves, New South Wales, and their geoheritage significance
Published in Australian Journal of Earth Sciences, 2019
V. Semeniuk, I. G. Percival, M. Brocx
The limestones at Bowan Park and at Cliefden Caves, although today only separated laterally by 30 km, are stratigraphically and lithologically different. The limestones at Bowan Park, specifically the Daylesford Limestone, although lithologically and paleontologically varied, are predominantly skeletal wackestone, with lime mudstone as the pervasive matrix (Figure 7), and with fossil content relatively minor compared with limestones at Cliefden Caves. The upper part of the Daylesford Limestone is massively calcreted (the Glenrae Limestone Member) and, in turn, pisolite- and lithoclast-dominated (the Davys Plain Limestone Member). The limestones at Cliefden Caves, specifically the Fossil Hill Limestone, also is paleontologically varied, with a variety of limestone types (from skeletal wackestone to pelletal grainstones to skeletal, lithoclast and calcrete ooid grainstones), but richly fossiliferous with a diverse and more abundant biota than that of the Daylesford Limestone, and locally with biostromes and small bioherms composed of framework-building organisms (Figure 8).