Hydrological and environmental research at UNLV is balanced between field, laboratory, and numerical studies. Investigations range in scale from continental hydrology, to fundamental flow processes within individual pores and fractures. Noting that Southern Nevada provides a natural laboratory for such studies, much, but not all of our research addresses questions regarding the protection, development, and remediation of water resources in highly stressed arid environments.
David K. Kreamer: Professor
Hydrogeology, Contaminant Transport by Groundwater
Elisabeth (Libby) M. Hausrath: Associate Professor
Geochemistry, Water: rock interactions, Hydrogeochemistry, Geomicrobiology, Chemical weathering, Soil-forming processes
Matthew S. Lachniet: Professor
Quaternary Geology, Paleoclimatology, Isotope Geochemistry
Michael J. Nicholl: Associate Professor
Vadose Zone Hydrology, Environmental Fluid Mechanics, and Geological Engineering
Vadose zone research at UNLV focuses on understanding fluid migration in arid to semi-arid terrain. Specific research areas include: water flux across the air-soil interface, moisture redistribution in the root zone, and deep recharge. Each of these topics is considered through field, laboratory, and numerical investigations. Long-term water balance studies in highly instrumented outdoor lysimeters (with and without plant cover) provide critical information required for conceptual model development, instrument calibration, and explanation of field observations.
Research activities include both dissolved and non-aqueous phase contaminants, as well as low solubility constituents released by the latter. Column studies, batch testing, and unique laboratory tests designed to address site specific conditions or techniques (e.g., cellulose media, thermal enhanced remediation, surging) are used to assess remediation strategies. The potential for geophysical monitoring of surfactant enhanced remediation is considered at the bench and column scales.
Commercial and self-developed numerical models are used by UNLV faculty to consider hydrologic processes at scales ranging from continental down to the core scale. Model types include stochastic, discrete (logical), and discretized PDE solvers (finite-difference, finite-element). Numerical codes are applied to understand diverse processes, including: coupling between hydrologic-climatic processes at the continental scale, radionuclide transport in unsaturated dual-permeability media, and uncertainty limits on unsaturated flow predictions based on sparse data.
Faculty research employs coupled laboratory experimentation and numerical simulation to explore the fundamental mechanisms that control fluid flow in geologic media. Processes that do not conform to the Darcian conceptual model, such as: unstable flow, multi-phase flow, fracture flow, and capillary barriers are explored so that critical phenomena may be abstracted for use in improved conceptual models for flow and transport.
Stable isotopes, radioactive isotopes, and natural tracers are used by Geoscience faculty to understand large scale flow systems in arid regions. Sources for spring water, root-driven water migration, recharge on bare soils, and evaporation rates are difficult to measure in the field. Water and soil chemistry are used to address these issues.