Rotary drills, diamond drills and percussive drills have been extensively used in open pits, quarries and construction sites. The prediction of the penetration rate of drilling machines is very important in the cost estimation and the planning of the rock excavation projects. The rock modulus ratio, which is the ratio of elastic modulus to compressive strength, indicating the deformability, is ...

The objective of this study was to establish a rock physics model of North Sea Paleogene greensand. The Hertz-Mindlin contact model is widely used to calculate elastic velocities of sandstone as well as to calculate the initial sand-pack modulus of the soft-sand, stiff-sand, and intermediate-stiff-sand models. When mixed minerals in rock are quite different, e.g., mixtures of quartz and glaucon...

the prediction of porosity is achieved by using available core and log data; however, the estimationof permeability is limited to the scare core data. hence, porosity and saturation data through theframework of flow units can be used to make an estimation of reservoir permeability. the purposeof this study is to predict the permeability of a carbonate gas reservoir by using physical-basedempiri...

The need for sustainable catalysts for an efficient hydrogen evolution reaction is of significant interest for modern society. Inspired by comparable structural properties of [FeNi]-hydrogenase, here we present the natural ore pentlandite (Fe4.5Ni4.5S8) as a direct 'rock' electrode material for hydrogen evolution under acidic conditions with an overpotential of 280 mV at 10 mA cm(-2). Furthermo...

successful application of a tbm in a project requires investigating both the ground conditions and the machine and backup system design features. prediction of the machine performance is very important as it has a big effect on the duration of the project and the costs. in this respect, both penetration rate and advance rate must be estimated. utilization factor, which depends on the type of op...

Seismic data are used in petroleum exploration to define geologic features in the subsurface. Recent advancements in seismic exploration have examined the effect of fluid and rock properties on seismic attributes. These advancements may provide improved reservoir characterization using techniques examined here. This is accomplished two parts; first, a study of fluid properties and their effect ...

The growth of microbial biofilms and various biomineralization phenomena can lead to the formation of stable layers and veneers on rocks known as 'rock varnishes' that can stabilize surfaces and protect from further weathering. This article describes the potential application of fungal systems for bioprotection of rock and mineral-based substrates and the evidence to support this concept of uti...

It is generally accepted that the identification and characterisation of discontinuities in discontinuous rock masses is one of the most important aspects in rock mass modelling. Traditional manual field survey methods for gathering discontinuity properties are biased, hazardous, difficult and time-consuming. This paper describes a computer approach, based on terrestrial laser scan data, which ...

The paper examines the interaction between host rock and a clay-based engineered barrier in the context of deep underground disposal of high-level radioactive waste. A large scale ‘‘in situ’’ heating test currently under way in the underground Grimsel Rock Laboratory (GRL; Switzerland) is adopted as a representative case for study. The main features of the behaviour of the rock/barrier system h...