Deriving permeability distributions from fractal Gaussian tracer returns

Abstract

Tracer returns in geothermal fields yield information about the connectivity between injection and production wells. We derive the equivalence between tracer returns described by a fractal Gaussian distribution, where diffusivity is scaled linearly with time, and tracer returns implied by one-sided Gaussian distributions of permeability. In this case, asymptotic tracer returns decay as the inverse square of time, and tracer returns are higher than predicted by methods assuming that asymptotic tracer returns decay exponentially with time. References

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