ONE HUNDRED YEARS OF GREAT BASIN HYDROGEOLOGY -- WHERE DO WE GO FROM HERE?

The ground-water knowledge of the Great Basin has paralleled the advancements in the state of hydrogeology and has made tremendous strides in the past 50 years. Although interbasin flow of ground water was recognized in the early part of the 20th century, the definition of flow systems and general acceptance of regional flow systems in the Great Basin awaited the pioneering efforts of Maxey and Eakin who devised empirical quantitative procedures for evaluating the hydrologic balance of individual basins. Conceptual models of the regional flow potential in the region are premised on regional permeability distribution as influenced by the lithologic and structural geologic framework of the region. Several generations of models in the Great Basin have culminated in a model which melds comprehensive and state of the art mathematical modeling techniques, geology, and ground-water hydrology. The regional potentiometric surface provides basic information on the hydraulic flow field useful in expanding the hydrologic understanding of the flow system by facilitating the simulation of boundaries and forming a regional context within which to frame studies in collateral disciplines such as geochemical and isotope studies of ground water, recharge models and geothermal heat flow models. The currently available computer capabilities provide for a broader scope and greater sophistication of analyses of hydrogeologic and related phenomena.