GroMoPo Metadata for Erzin groundwater basin model

The spatial and transient behavior of the coupled mechanism of saltwater and freshwater how throughout the Erzin, Turkey, groundwater basin was analyzed to forecast the position of the interface under a particular set of recharge and discharge conditions. The density-driven saltwater intrusion process was simulated with the use of a finite-element model. Physical parameters, initial heads, and boundary conditions of the basin were defined on the basis of available field data, and an areal, steady-state groundwater model was constructed to calibrate the observed head values corresponding to the initial development phase of the aquifer. Initial and boundary conditions determined from the areal calibration were used to evaluate the aquifer's dispersivities and the porosity in a steady-state, cross-sectional analysis. Consequently, the initial position of the salt concentration distribution was calibrated under steady-state conditions. The initial concentration distribution was then marched through time under discharge and recharge conditions, and the present-day position of the interface was predicted. In the cross-sectional simulation, the saltwater front was predicted to move inland during the discharge period, whereas in the recharge period the heads were pre dieted to recover to their initial positions with no significant movement of saltwater. The present-day distribution of salt concentrations was estimated via a 25-year simulation. Results indicate that the width of the dispersion zone has increased during this period and the saltwater encroachment has gradually been slowed down, tending toward a new steady-state position.本研究针对土耳其埃尔津（Erzin）地下水盆地内咸水与淡水耦合运移的空间及瞬态行为展开分析，旨在预测特定补给与排泄条件下咸淡水界面的位置。本研究采用有限元模型（finite-element model）模拟了密度驱动的咸水入侵过程。以研究区可获取的野外实测数据为基础，确定了该地下水盆地的物理参数、初始水头（initial heads）及边界条件，并构建了面状稳态地下水模型，用于率定对应含水层（aquifer）初始发育阶段的实测水头值。通过面状率定得到的初始条件与边界条件，被用于稳态剖面分析中，以评估含水层的弥散系数（dispersivities）与孔隙度（porosity）。据此，在稳态条件下完成了盐浓度分布初始位置的率定。随后，在补给与排泄条件下，对初始浓度分布进行时间步进模拟，进而预测当前咸淡水界面的位置。在剖面模拟中，预测得到排泄期内咸水锋面向内陆迁移；而在补给期内，水头将恢复至初始位置，咸水无明显运移。通过25年时长的模拟，估算得到了当前的盐浓度分布情况。结果显示，该时段内弥散带宽度有所增加，咸水入侵进程逐渐放缓，最终将趋于新的稳态位置。