Fluid Flow and Heat Transport Computation for Power-Law Scaling Poroperm Media. (19th October 2017)

• Record Type: Journal Article
• Authors: Leary, Peter; Malin, Peter; Niemi, Rami
• Other Names: El-Amin Mohamed Fathy Academic Editor.
• Is Part Of: Geofluids. Volume 2017(2017)
• Publication Date: 2017-10-19
• Subjects: Hydrogeology -- Periodicals; Sedimentary basins -- Periodicals; Fluids -- Migration -- Periodicals; Groundwater flow -- Periodicals; Geothermal resources -- Periodicals; Fluid dynamics -- Periodicals; Earth -- Crust -- Periodicals; 551.49
• DOI: 10.1155/2017/9687325
• Languages: English
• ISSNs: 1468-8115

Abstract

Abstract : In applying Darcy's law to fluid flow in geologic formations, it is generally assumed that flow variations average to an effectively constant formation flow property. This assumption is, however, fundamentally inaccurate for the ambient crust. Well-log, well-core, and well-flow empirics show that crustal flow spatial variations are systematically correlated from mm to km. Translating crustal flow spatial correlation empirics into numerical form for fluid flow/transport simulation requires computations to be performed on a single global mesh that supports long-range spatial correlation flow structures. Global meshes populated by spatially correlated stochastic poroperm distributions can be processed by 3D finite-element solvers. We model wellbore-logged Dm-scale temperature data due to heat advective flow into a well transecting small faults in a Hm-scale sandstone volume. Wellbore-centric thermal transport is described by Peclet number P e ≡ a 0 φ v 0 / D (a 0 = wellbore radius, v 0 = fluid velocity at a 0, φ = mean crustal porosity, and D = rock-water thermal diffusivity). The modelling schema is (i) 3D global mesh for spatially correlated stochastic poropermeability; (ii) ambient percolation flow calibrated by well-core porosity-controlled permeability; (iii) advection via fault-like structures calibrated by well-log neutron porosity; (iv) flow P e ~ 0.5 in ambient crust and P e ~ 5 for fault-borne advection.