This study concerned a stretch of 17 km of a 94-km highway alignment in Southeastern Nigeria that has a high incidence of pavement failure arising from subgrade failure. The subgrade of this section of the roadway is composed of Ekenkpon shale, New Netim marl, and Nkporo shale. Under the Unified Soil Classification System, the shales classify as OH (organic clay) and the marl classifies as MH (...

Advanced techniques have greatly promoted the exploitation of shale gas from shale matrix with low permeability. But the gas transport mechanism in shale is still unclear. Due to the multi-scale pore systems in a shale reservoir, viscous flow, slip flow, Knudsen diffusion and adsorption/desorption should be applied to the flowing equation so that it can properly predict gas flow dynamics. Multi...

What do we know about ageing at work? Evidence-based fitness for duty and health in fire fighters. The current enthusiasm for fracking takes me back to the oil crisis of the late 1970s. I had been asked to see a post-thoracotomy patient and, when he recovered, found that his lesion had been pneumoconiotic. When I enquired which mine he worked in, he told me that it had been a shale mine and sin...

Reservoir shale has the characteristics of bedding planes, strong anisotropy, and imbibition ability under ultralow water saturation, which an important impact on wellbore stability horizontal wells. Therefore, physical chemical properties reservoir were analyzed, a mechanics model was established considering elasticity strength anisotropy. The analyzed anisotropy parameters formation condition...

The shale gas exploration and development is now a delicate and controversial subject. It is often assumed that unconventional exploration and extraction automatically brings prosperity for local, national and regional economies. In this paper, we argue that shale gas development requires a contextualized understanding of regional issues. We are also trying to identify the opportunities and the...

Starch is one of the most widely used biopolymers in water based drilling fluids to control fluid loss. The thermal stability of starch in common drilling fluids is low (93 °C). In this study, the thermal stability of starch has been evaluated in sodium/potassium formate and potassium chloride fluids. Samples of mud were prepared by formate salts (sodium and potassium) and potassium chloride wi...

Evaluation of the geomechanical properties of shales, especially weak ones is always problematic. The Missouri Department of Transportation (MODOT) recently undertook a major research initiative to achieve significant and recurring cost savings for MODOT by developing improved, technically sound design specifications. Test drilling in shale was conducted; Boreholes were typically drilled in pai...

Oil derived from oil shale deposits is known to contain many organic complexes. The formation of carcinogenic hydrocarbons is temperature-dependent and is associated with retorting of the oil. Furthermore, oil shale is a rich source of inorganic elements such as the metals. Biological studies have demonstrated that concentrated extract of tars from combustion of shale oil are carcingenic to the...

Landslides along the Missouri and Kansas rivers will affect existing structures and potential development in the Kansas City metropolitan area. A pilot landslide-mapping project was conducted in the vicinity of Atchison, Kansas, to inventory existing landslides and determine the factors that caused them. Landslides are generally controlled by the slope morphology, geology, soils, and moisture c...

BACKGROUND The United States has experienced a boom in natural gas production due to recent technological innovations that have enabled this resource to be produced from shale formations. OBJECTIVES We reviewed the body of evidence related to exposure pathways in order to evaluate the potential environmental public health impacts of shale gas development. We highlight what is currently known ...