Groundwater recharge and hydrodynamics of complex volcanic aquifers with a shallow saline lake: Laguna Tuyajto, Andean Cordillera of northern Chile.

Estimating groundwater recharge in arid regions with seasonal snow cover, as in the Andean Altiplano of northern Chile, is important for sustainable development policies and the effective management of scarce resources in a high water demanding zone, as fragile ecosystems depends on a stable water contribution. This research aims to evaluate and quantify rainfall and snowfall contribution to aquifer recharge while assessing the factors that control the hydrodynamics in such areas, based in the knowledge of the better documented Tuyajto Lake in the Tuyajto catchment/basin. The modeling framework involves an energy balance of the snow cover, a soil water balance and a groundwater flow and chloride transport model.

Land surface temperature as an indicator of the unsaturated zone thickness: A remote sensing approach in the Atacama Desert.

Land surface temperature (LST) seems to be related to the temperature of shallow aquifers and the unsaturated zone thickness (∆Z). That relationship is valid when the study area fulfils certain characteristics: a) there should be no downward moisture fluxes in an unsaturated zone, b) the soil composition in terms of both, the different horizon materials and their corresponding thermal and hydraulic properties, must be as homogeneous and isotropic as possible, c) flat and regular topography, and d) steady state groundwater temperature with a spatially homogeneous temperature distribution. A night time Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image and temperature field measurements are used to test the validity of the relationship between LST and ∆Z at the Pampa del Tamarugal, which is located in the Atacama Desert (Chile) and meets the above required conditions.

Crystalline particle packings on constant mean curvature (Delaunay) surfaces.

We investigate the structure of crystalline particle arrays on constant mean curvature (CMC) surfaces of revolution. Such curved crystals have been realized physically by creating charge-stabilized colloidal arrays on liquid capillary bridges. CMC surfaces of revolution, classified by Delaunay in 1841, include the 2-sphere, the cylinder, the vanishing mean curvature catenoid (a minimal surface), and the richer and less investigated unduloid and nodoid.