Theoretical and Field Studies on Basin-scale Groundwater Flow Dr. Xiao-Wei Jiang China University of Geosciences (Beijing) Most large basins in China are abundant in energy and mineral resources, and some basins are also important grain production bases. With the increasing industrial and agricultural demands for water resources, overexpoliation of groundwater in some basins has caused a series of geoenvironmental problems. A clear understanding on the pattern of basin-scale groundwater flow is critical for sustainable development of groundwater, and is also one of the challenges facing modern hydrogeology. During the development of regional hydrogeology, the theory of regional groundwater flow initially proposed by Tóth (1963) effectively characterizes the movement of groundwater in drainage basins. Due to the periodic undulations in water table reflecting topography, local, intermediate, and regional flow systems could develop in a drainage basin, and the dynamics and chemistry of groundwater in each flow system are relatively independent. However, the theory still has some unsolved problems. In this talk, recent advances in the theory of regional groundwater flow are to be introduced. (1) Analytical analysis of dynamics of groundwater in drainage basins, especially around stagnation points. (2) The influencing factors of distribution of groundwater flow systems in drainage basins. (3) Numerical analysis of groundwater age distribution in drainage basins, especially around stagnation points. (4) Field studies on accumulation of transported matters around stagnation points in the Ordos Basin, Northwestern China. CONTINUED BIOGRAPHY Xiao-Wei Jiang obtained his bachelor’s degree (2003), Master’s degree (2006) and PhD (2011) in China University of Geosciences (Beijing). Currently he is a lecturer at the School of Water Resources and Environment, China University of Geosciences (Beijing). His research focuses on characterization of large scale heterogeneity of aquifer systems and basin-scale groundwater flow. He is the author or co-author of more than 10 papers in international journals, including Water Resources Research, Geophysical Research Letters, Hydrogeology Journal and International Journal of Rock Mechanics and Mining Sciences.