GroMoPo Metadata for Death Valley regional model

A regional-scale, steady-state, saturated-zone ground-water flow model was constructed to evaluate potential regional ground-water flow in the vicinity of Yucca Mountain, Nevada. The model was limited to three layers in an effort to evaluate the characteristics governing large-scale subsurface flow. Geoscientific information systems (GSIS) were used to characterize the complex surface and subsurface hydrogeologic conditions of the area, and this characterization was used to construct likely conceptual models of the flow system. Subsurface properties in this system vary dramatically, producing high contrasts and abrupt contacts. This characteristic, combined with the large scale of the model, make zonation the logical choice for representing the hydraulic-conductivity distribution. Different conceptual models were evaluated using sensitivity analysis and were tested by using nonlinear regression to determine parameter values that are optimal, in that they provide the best match between the measured and simulated heads and flows. The different conceptual models were judged based both on the fit achieved to measured heads and spring flows, and the plausibility of the optimal parameter values. One of the conceptual models considered appears to represent the system most realistically. Any apparent model error is probably caused by the coarse vertical and horizontal discretization. (C) 1999 Elsevier Science Ltd. All rights reserved.

为评估内华达州尤卡山周边区域的潜在地下水流场，本研究构建了区域尺度稳态饱和区地下水流模型。为解析控制大型尺度地下水流的主控特征，该模型仅设置三层结构。研究借助地球科学信息系统（Geoscientific Information Systems，GSIS）刻画研究区复杂的地表与地下水文地质条件，并以此构建该水流系统的合理概念模型。本系统内地下属性差异显著，形成了高对比度的突变接触界面；结合模型的大尺度特性，分区成为表征水力传导度分布的合理选择。针对不同概念模型，研究通过敏感性分析开展评估，并借助非线性回归求解最优参数值，以使模拟水头、流量与实测值达到最佳匹配。最终依据模型对实测水头与泉水流量的拟合效果，以及最优参数值的合理性，对各概念模型进行评判。其中一款概念模型最贴近实际系统的特征。本模型尚存的表观误差，大概率源于较粗的垂直与水平离散化。本研究内容版权归1999年爱思唯尔科学有限公司所有，保留所有权利。