The job of a production facility is to separate the well stream into three components, typically called "phases" (oil, gas, and water), and process these phases into some marketable product(s) or dispose of them in an environmentally acceptable manner. In mechanical devices called "separators" gas is flashed from the liquids and "free water" is separated from the oil. These steps remove enough light hydrocarbons to produce a stable crude oil with the volatility (vapor pressure) to meet sales criteria. Figures 1-1 and 1-2 show typical separators used to separate gas from liquid or water from oil. Separators can be either horizontal or vertical in configuration <...>

Underground coal mining disturbs not only the overburden strata, but also the immediate floor strata. The former is much more significant because it involves strata from the seam level all the way to the surface, where structures and water resources important to human activities are located. The issues associated with the movement of overburden strata due to underground coal mining together comprise the subject of surface subsidence.

More than a century has passed since Lord Rayleigh (1885) first investigated “the behaviour of waves upon the plane free surface of an infinite homogeneous isotropic elastic solid, their character being such that the disturbance is confined to a superficial region, of thickness comparable to the wave-length.” Rayleigh immediately recognized their importance stating that “it is not improbable that the surface waves here investigated play an important part in earthquakes, and in the collision of elastic bodies.” Since then, surface waves have come to play an important part in many other disciplines as well, including material science, geophysics, nondestructive testing, and engineering site characterization. When used for near-surface site characterization, the objective is usually to determine the shear wave velocity and/or shear damping ratio one-dimensional (1D) profiles for a variety of applications, including earthquake site response, dynamic soil–structure interaction, nondestructive pavement testing, evaluation of ground modification, and so on. <...>

The series focuses on efficiency, enhanced production, emissions-reduction, carbon capture, and gas resource sustainability. It aims to address and solve specific and relevant problems for those currently working in the natural gas industry or researching aspects of it. The world is striving for zero-carbon energy supply, which is for some politicians, regulators, and certain sectors of public opinion interpreted, over-simplistically, to mean that over the next few decades the use of natural gas will be phased out, implying that the industry will gradually contract into oblivion.