We use the ultrasonic transmission method to measure P-, SH-, and SV-wave velocities for Chelmsford Granite, Chicopee Shale, and Berea Sandstone in different directions up to 1000 bars confining pressure. The velocity measurements indicate that these three rocks are elastically anisotropic. The stiffness constants, dynamic Young's moduli, dynamic Poisson's ratios, and dynamic bulk moduli of the...

OBJECTIVES The task of grinding sandstone with a 5-inch angle grinder is a major source of exposure to respirable crystalline silica (RCS), known to cause diseases such as silicosis and lung cancer among workers who work with these materials. A shroud may be a suitable engineering control for this task. The objectives of this study were to evaluate the effectiveness of four commercially availab...

Brand, L., 1979. Field and laboratory studies on the Coconino Sandstone (Permian) vertebrate footprints and their paleoecological implications. Palaeogeogr., Palaeoclimatol., Palaeoecol., 28: 25-38. The fossil footprints in the Coconino Sandstone have long been considered to be evidence for eolian deposition. I conducted field study of the fossil footprints in Hermit Basin, the Grand Canyon, an...

BACKGROUND Reactive-transport simulation is a tool that is being used to estimate long-term trapping of CO2, and wellbore and cap rock integrity for geologic CO2 storage. We reacted end member components of a heterolithic sandstone and shale unit that forms the upper section of the In Salah Gas Project carbon storage reservoir in Krechba, Algeria with supercritical CO2, brine, and with/without ...

The Pass Peak Formation is a Tertiary basin-flank deposit exposed throughout much of the Hoback Basin; a depression physiographically distinct from, but structurally continuous with, the northern Green River Basin. Two lithofacies of the Pass Peak Formation are identified. A northern quartzite conglomeratesandstone facies, possibly as thick as 3200 ft, intertongues southward with a sandstone-si...

Numerical micropermeametry is performed on three dimensional porous samples having a linear size of approximately 3 mm and a resolution of 7.5 μm. One of the samples is a microtomographic image of Fontainebleau sandstone. Two of the samples are stochastic reconstructions with the same porosity, specific surface area, and two-point correlation function as the Fontainebleau sample. The fourth sam...

The Bayon temple in Angkor Thom, Cambodia has shown serious deterioration and is subject to the formation of various pigmented biofilms. Because biofilms are damaging the bas-reliefs, low reliefs engraved on the surface of sandstone, information about the microbial community within them is indispensable to control biofilm colonization. PCR-denaturing gradient gel electrophoresis (DGGE) analysis...

A sandstone outcrop exposed to freshwater seepage supports a diverse assemblage of photosynthetic microbes. Dominant taxa are two cyanophytes (Oscillatoria sp., Rivularia sp.) and a unicellular green alga (Palmellococcus sp.). Less abundant taxa include a filamentous green alga, Microspora, and the desmid Cosmarium. Biologic activity is evidenced by measured levels of chlorophyll and lipids. Bi...

INTRODUCTION Modeling can be a useful tool to find out how the distributions of hospital length of stay (LOS) and the factors affecting the length of stay. The present study aims to determine factors affecting the length of stay and selecting suitable statistical models. MATERIAL AND METHOD this is a cross - sectional study of 565 patients who were treated in the intensive care unit of Imam K...

OBJECTIVES Crystalline silica occurs as a significant component of many traditional materials used in restoration stonework, and stoneworkers who work with these materials are potentially exposed to stone dust containing respirable crystalline silica (RCS). Exposure to RCS can result in the development of a range of adverse health effects, including silicosis and lung cancer. An understanding o...