Publications by authors named "Donald W Vasco"
Subsidence induced by groundwater depletion is a grave problem in many regions around the world, leading to a permanent loss of groundwater storage within an aquifer and even producing structural damage at the Earth's surface. California's Tulare Basin is no exception, experiencing about a meter of subsidence between 2015 and 2020. However, understanding the relationship between changes in groundwater volumes and ground deformation has proven difficult.
View Article and Find Full Text PDFRange change data, obtained from Synthetic Aperture Radar satellites, form the basis for estimates of aquifer volume change in California's Central Valley. The estimation algorithm incorporates a function penalizing changes far from known well locations, linking the aquifer volume changes to agricultural, industrial, and municipal pumping within the Tulare basin. We show that the range changes are compatible with the hypothesis that the source of aquifer volume changes are variations in effective pressure around documented wells.
View Article and Find Full Text PDFArticle Synopsis
- The study derives macroscopic laws for solute advection and diffusion in porous media without limiting pore space geometry or time evolution.
- Special emphasis is placed on the definition and symmetry of the dispersion tensor, revealing it to be asymmetric due to the advective component in the advection-diffusion equation.
- The research confirms the dispersion tensor obeys flow-reversal symmetry at any Péclet number, and showcases simulations that illustrate the antisymmetry of its off-diagonal components.