Subsurface fluid flow

A permeable reactive barrier (PRB) is defined as an in situ method for remediating contaminated groundwater that combines a passive chemical or biological treatment zone with subsurface fluid flow management. Treatment media may include zero-valent iron, chelators, sorbents, and microbes to address a wide variety of groundwater contaminants, such as chlorinated solvents, other organics,... 

Kharaka Y. K., Thordsen J. J., Evans W. C., and Kennedy B. M. (1999b) Geochemistry and hydromechanical interactions of fluids associated with the San Andreas fault system, Cahfomia. In Faults and Subsurface Fluid Flow in the Shallow Crust, AGU Geophys. Monograph Series 113 (eds. W. C. Haneberg, L. B. Goodwin, P. S. Mozley, and J. C. Moore), pp. 129—148. 

The present hydrogeological framework of the sedimentary basin, which is characterized by the distribution, thickness and dip of porous and permeable hydrogeological units (aquifers/potential carrier-reservoir rocks, e.g. sands, sandstones, carbonates, fractured rocks) and poorly permeable hydrogeological units (aquitards/potential barrier rocks, e.g. shales, evaporites), and the location of geological structures and tectonic elements of importance for subsurface fluid flow, e.g. permeable or impermeable faults, unconformities... 

Increasingly since the mid-1970s, with the advent of high-speed digital computers, process-based mathematical models of coupled subsurface fluid flow, solute transport, and geochemistry have been used to assess subsurface water contamination impacts. 

An important safety feature on every modern rig is the blowout preventer (BOP). As discussed earlier on, one of the purposes of the drilling mud is to provide a hydrostatic head of fluid to counterbalance the pore pressure of fluids in permeable formations. However, for a variety of reasons (see section 3.6 Drilling Problems ) the well may kick , i.e. formation fluids may enter the wellbore, upsetting the balance of the system, pushing mud out of the hole, and exposing the upper part of the hole and equipment to the higher pressures of the deep subsurface. If left uncontrolled, this can lead to a blowout, a situation where formation fluids flow to the surface in an uncontrolled manner. 

Goldhaber, M.B., Lee, R.C., Hatch, J.R. (2003) Role of large scale fluid-flow in subsurface arsenic enrichment, in Arsenic in Ground Water (eds A.H. Welch and K.G. Stollenwerk), Kluwer Academic Publishers, Boston, MA, pp. 127-64. 

Some of the basic processes in the formation of secondary porosity are similar to those for formation of carbonate cements. A solution of proper composition must be generated by subsurface processes, and this solution must also flow through the formation in which the dissolution reaction takes place in sufficient quantities to transport the dissolved carbonate. The primary differences between cement and secondary porosity formation are that an undersaturated solution must be generated rather than a supersaturated solution, and that while cement formation reduces porosity and can inhibit flow, formation of secondary porosity increases porosity and can result in enhanced flow of subsurface fluids. 

The flow of groundwater and other subsurface fluids is described by Darcy s law (Darcy, 1856). Hydraulic conductivity, the constant in Darcy s... 

Yeh G. T., Li M. H., and Siegel M. D. (2002) Fluid flow and reactive chemical transport in variably saturated subsurface media. In Environmental Fluid Mechanics (eds. H. Shen, A. Cheng, K. Wang, M. Teng, and C. Liu). American Society of Civil Engineers, pp. 207-256. 

Darcy s law (Darcy, 1856) is a phenomenological law that is valid for the viscous flow of a single-phase fluid (e.g. groundwater flow) through porous media in any direction. This basic law of fluid flow is a macroscopic law providing averaged descriptions of the actual microscopic flow behaviour of the fluids over some representative elementary volume of the porous medium. For isothermal and isochemical subsurface conditions, the law can be written as (Hubbert, 1953)... 

Bredehoeft, J.D., Blyth, C.R., White, W.A. and G.B. Maxey, 1963. A possible mechanism for concentration of brines in subsurface formations. The American Association of Petroleum Geologists Bulletin, Vol. 47, no. 2, pp. 257-269 Bredehoeft, J.D., Djevanshir, R.D. and K.R. Belitz, 1988. Lateral fluid flow in a compacting sand-shale sequence South Caspian Basin. The American Association of Petroleum Geologists Bulletin, Vol. 72, no. 4, pp. 416-424... 

Willet, S.D. and D.S. Chapman, 1989. Temperatures, fluid flow and heat transfer mechanisms in the Uinta Basin. In Beck, A.E., Garven, G. and L. Stegena (eds.), 1989. Hydrogeological regimes and their subsurface thermal effects. Geophysical Monograph 47/ lUGG Volume 2, pp. 29-33... 

Role of Large Scale Fluid-Flow in Subsurface Arsenic Enrichment... 

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