The present study was designed to gain insight into the protists and fungi that made up the microbiota in the past, fossilized in two different substrates: amber and sandstone. The amber, dated as Lower Cretaceous, was from Álava in northern Spain, while fossil-bearing sandstone rocks were collected from the Linnaeus terrace and Mount Fleming regions of Antarctica. When examining this type of i...

Bioturbation long has been ‘blamed’ for eliminating late Proterozoic-style sedimentary structures and fabrics. While the presence of diverse and complex burrows in lowermost Cambrian strata is indisputable, analysis of Precambrian– Cambrian successions in southeast Newfoundland demonstrate that this burrowing style did not produce typical Phanerozoic-style ichnofabrics. Three hundred meters of ...

the electrical resistivity of hydrocarbon reservoir rocks is an important parameters in the calculation of water and oil saturation percent in both carbonate and sandstone reservoir rocks.in this regard, most studies have concentrated on the confining  pressure on cementation factor and electrical resistivity in sandstone reservoir rocks. in this study the effect of confining pressure on cement...

The Cambrian-age Mt. Simon Sandstone, deeply buried within the Illinois Basin of the midcontinent of North America, contains quartz sand grains ubiquitously encrusted with iron-oxide cements and dissolved ferrous iron in pore-water. Although microbial iron reduction has previously been documented in the deep terrestrial subsurface, the potential for diagenetic mineral cementation to drive micro...

The noncarbonaceous Ediacaran discs of variable morphologies from the Jodhpur Sandstone Formation of the Marwar Supergroup, western Rajasthan, suggest different biologic affinities of plant and animal kingdom. These discs are commonly preserved on the bedding surfaces of siliciclastic sandstone and shale in strong positive relief and appear to possess a flexible to rigid body. Discs assignable ...

We compare the quantitative microstructural properties of Berea Sandstone with stochastic reconstructions of the same sandstone. The comparison is based on local porosity theory. The reconstructions employ Fourier space ltering of Gaussian random elds and match the average porosity and two-point correlation function of the experimental model. Connectivity properties of the stochastic models dii...

due to their widespread availability, sandstones are commonly used as a natural stone for buildings, monuments and sculptures. in thecurrent study, nine sandstone samples from the upper red formation (specified by the letters a, b, c, cg, s, s1, sh, tr and min)were studied from a petrophysical point of view and their durability was evaluated. then, their suitability as building stones wasassess...

a key parameter for the application of polymer gels in water shut off treatment is the adsorption of polymer gel onto the rock surface. so, the adsorption properties of a nanocomposite hydrogel were discussed in this research by crosslinking of sulfonated polyacrylamide/sodium montmorillonite aqueous solutions with chromium triacetate. the x-ray diffraction patterns indicated that exfoliated ty...