Presentation 1: The court case on Australia’s largest prospective coal mine: Reflecting on the failure to comply with hydrogeological principles
Summary: One of the world’s largest coal mines is proposed for construction in close proximity to a set of springs that supports endemic ecosystems and that holds great importance to Indigenous Australians. The decision to approve the mine is underpinned by misconceptions and considerable uncertainty on the back of a deplorable lack of field measurements. Adrian Werner was an expert witness to the case, and reveals the process that ultimately led to approval on the mine despite critical and fundamental problems with the investigation into potential impacts caused by the mine void. Details of the hydrogeological misconceptions that accompanied the final decision are detailed in a Journal of Hydrology article recently published by Adrian and his colleagues: Currell MJ, Werner AD, McGrath C, Webb JA, Berkman M (2017) Problems with the application of hydrogeological science to regulation of Australian mining projects: Carmichael Mine and Doongmabulla Springs, Journal of Hydrology 548: 674-682, doi: 10.1016/j.jhydrol.2017.03.031.
时间：2017年5月10日上午10：00-11：00
地点：水电馆401
Presentation 2: A numerical modelling analysis to characterize active and passive forms of seawater intrusion
Summary: Active and passive seawater intrusion (SWI) arise when the freshwater head gradient slopes downwards towards land and the sea, respectively. However, a third category exists (i.e., passive-active SWI), whereby active SWI occurs inland of a mound in piezometric surface, whereas passive SWI occurs on the seaward side of the mound. In this study, numerical modelling is used to characterize the three forms of SWI, including an overview of the transient features of active SWI. The analysis provides guidance on some of the key attributes of each SWI class, as an extension to previous SWI research that offers limited differentiation between the various SWI types. Threshold parameter combinations for the onset of each form of SWI are provided, as derived from sharp-interface, steady-state analytical solutions. Dispersive aspects of SWI are then explored using numerical simulation. Important differences between the various forms of SWI include the salinization of the watertable that occurs under active SWI and in the absence of recharge, and the formation of persistent freshwater lenses in aquifers experiencing active SWI but also subject to surface recharge. Attempts to characterize transient active SWI processes, in terms of buoyancy, advective and dispersive processes, using dimensionless ratios that are drawn from previous studies of steady-state SWI, highlight the complex, nonlinear relationships that govern active SWI, even for idealized circumstances.
时间：2017年5月10日下午3：30-4：30
地点：水电馆420
Adrian Werner is Professor of Hydrogeology at Flinders University, and a member of the National Centre for Groundwater Research and Training. Adrian currently holds an Australian Research Council Future Fellowship, through which he is leading a four-year investigation of Australia’s coastal groundwater resources. Adrian spent his formative professional years working with the Queensland Government as a Water Resource Engineer, before completing his Ph.D. at the University of Queensland and then embarking on an academic career from 2006. He is an Associate Editor for Advances in Water Resources and Journal of Hydrology, and has published over 90 international journal articles. Since 2008, Adrian has been visiting the Nanjing Institute of Geography and Limnology, including through a President’s International Fellowship from the Chinese Academy of Sciences.
Presentation 3：Terrestrial freshwater lenses: Unexplored subterranean oases
Freshwater lenses are lenticular bodies of fresh groundwater that develop above more saline groundwater due to buoyancy forces. In contrast to the widely studied situation of freshwater lenses in coastal aquifers, the formation, location and persistence of freshwater lenses in terrestrial settings is poorly understood. This is despite saltwater being a common feature of inland aquifers, particularly in arid and semi-arid climates, where freshwater is critical for ecosystems and human endeavour. We identify and classify known terrestrial freshwater lenses (TFLs) using four formation categories, namely topography, geology, groundwater-surface water interaction and recharge mechanisms. The resulting typology highlights the importance of buoyancy forces in the formation of TFLs in otherwise unlikely situations, implying that TFLs may be more prevalent than previously thought. We conclude that TFLs represent some of the most vulnerable and precious freshwater resources on Earth, and require considerably more research to characterize formation dependencies and primary threats.
时间：2017年5月10日下午2：30-3：30
地点：水电馆420
Dr Tariq Laattoe is a post-doctoral research associate at Flinders University, and a member of the National Centre for Groundwater Research and Training. Following his Ph.D. on the investigation of flow solute and chemical reactions in the hyporheic zone, he was appointed to a project investigating the occurrence of freshwater lenses on the floodplains of the River Murray in Australia funded by the Australian Research Council and Professor Adrian Werner’s Future Fellowship project investigating Australia’s coastal groundwater resources. In these roles, Tariq used both physical and numerical experiments to investigate the variable-density effects of freshwater lenses. His most recent work reviews the global occurrence of freshwater lenses in terrestrial settings.
