Model data and procedure for a numerical investigation of the effects of model parameterization on the delineation of source protection zones under uncertainty

This dataset contains the model procedure used in the case study of "A numerical investigation of the effects of model parameterization on the delineation of source protection zones under uncertainty".

Source protection zone delineation has evolved over the past decades from fixed radius or analytical and numerical methods which do not consider uncertainty, to more complex stochastic numerical approaches where uncertainties are often considered within a Monte Carlo framework. Representation of aquifer heterogeneity in such approaches is based on geostatistical representation of hydraulic properties. In this paper we explored options for delineating a source protection zone, while considering the inherent uncertainty involved in characterizing hydraulic conductivity. We considered a representative pumping well in an unconfined alluvial aquifer under steady-state flow conditions, with the hydraulic conductivity distribution inferred from borehole lithology data in the West Melton area near Christchurch, New Zealand. Borehole data was obtained from the ECan Wells database, freely available online. Lithologies are categorized according to their inferred hydraulic flow and transport properties, using two to four hydrofacies groupings. Probabilistic source protection zones are determined for alternative lithology categorization scheme and hydrofacies conductivity parameterization methods.

The dataset contains the required files to reproduce the results using hydrofacies hydraulic conductivity calibration method 1 (from Table 1 in the paper) and for either lithology schemes 3a and 3b (shown in Figures 2 and 4). The dataset includes model files for modflow and modpath, and post-processing methods to generate probabilistic source protection zones. Further information can be found in the README.txt file in the dataset.

本数据集收录了在案例研究“在不确定性下对模型参数化对源保护区划定影响的数值研究”中使用的模型流程。源保护区划定方法在过去几十年中经历了演变，从固定半径或分析及数值方法，这些方法未考虑不确定性，发展到更为复杂的随机数值方法，其中不确定性通常在蒙特卡洛框架内予以考虑。此类方法中，含水层异质性的表示基于水力性质的地理统计学表示。在本研究中，我们探讨了在表征水力传导率所固有的不确定性下划定源保护区的选项，考虑了一个在非约束性冲积含水层中，在稳态流动条件下的代表性抽水井，其水力传导率分布由新西兰基督城附近韦斯特梅尔顿地区的钻孔岩性数据推断得出。钻孔数据来源于ECan Wells数据库，该数据库可免费在线获取。岩性根据其推断的水力流动和输运特性进行分类，采用两种至四种水文相分组。对于替代的岩性分类方案和水文相传导率参数化方法，确定了概率源保护区。数据集包含使用水文相水力传导率校准方法1（见论文中的表1）和岩性方案3a和3b（如图2和4所示）重现结果的必要文件。数据集包括MODFLOW和MODPATH的模型文件，以及生成概率源保护区的后处理方法。更多详细信息可在数据集中的README.txt文件中找到。