Outcrop Characterization of Heterogeneity: Explicit Linkage of Hydrological and Sedimentological Properties

小行星9706116 对非均质含水层露头类似物的实地沉积学和水文学研究提供了地下信息未实现的非均质性的概念化，并提供了一种基于井数据插值的流行随机模型的有效性和性能评估方法。 这种方法在碳氢化合物工业中广泛使用了几十年，但很少应用于水文问题。 充分暴露的裂谷盆地冲积层的沉积学研究将通过渗透率的现场测量来补充，从而允许指定具有确定的水力传导率、形状和边界的水文相，这些水文相与其分布与形成含水层材料的沉积过程有关的岩相相联系。 露头数据将被用来制定一个三维模型的异质性在典型的地下污染物迁移的情况下的规模。 研究现场的地层也将通过地质统计学技术进行模拟，使用测量剖面作为调节数据，其方式与使用井数据调节地下模型的方式大致相同。 模拟的预测能力将通过与露头数据的比较来衡量。 将对露头模型进行不同尺度（从几米到几十米）的露头定义异质性的流动模拟，以评估高分辨率预测流动路径和流速所需的数据数量和类型。 为露头表征选择的沉积环境对于理解美国西南部伸展盆地的含水层异质性特别重要，迄今为止的研究还没有充分描述具有水文地质重要性的沉积学特征。 在不对称伸展盆地中沉积的碎屑碎屑岩的最大体积是从上盘输送到主断层。 这些冲积斜坡相是裂谷盆地中最不为人所知的沉积。 该项目将通过提供新墨西哥州北方格兰德河裂谷中非常暴露的盆地充填序列内的水文相渗透性、形状和边界的详细三维文档，为冲积斜坡沉积物的含水层特征提供第一个露头模拟。

9706116 Smith Field sedimentological and hydrological studies of outcrop analogs for heterogeneous aquifers provide conceptualizations of heterogeneity unrealized by subsurface information and provide a means for assessing the validity and performance of popular stochastic models based on interpolation of well data. The approach, widely used for decades in the hydrocarbon industry, has seen little application to hydrological problems. Sedimentological studies of well-exposed rift-basin alluvium will be complemented by in-situ measurements of permeability, thus permitting designation of hydrofacies with defined hydraulic conductivity, shape, and boundaries that are linked with lithofacies whose distribution is related to depositional processes that formed the aquifer material. Outcrop data will be used to formulate a three-dimensional model of heterogeneity at the scale of typical subsurface-contaminant-migration scenarios. The study-site stratigraphy will also be simulated by geostatistical techniques using measured sections as conditioning data in much the same way as well data are used to condition subsurface models. The predictive ability of the simulation will be gauged by comparison to the outcrop data. The outcrop model will be subjected to flow simulations for varying scales (meters to tens of meters) of outcrop-defined heterogeneity to evaluate the quantity and type of data required for high-resolution prediction of flow paths and rates. The depositional environment selected for outcrop characterization is especially important for understanding aquifer heterogeneity in extensional basins of the southwestern United States, where studies to date have not adequately described the sedimentological characteristics that are of hydrogeological importance. The largest volume of clastic detritus deposited in asymmetric extensional basins is delivered from the hanging wall to the master fault. These alluvial-slope facies are the least well known deposits in rift basins. This projec t will produce the first outcrop analog for aquifer characteristics of alluvial-slope deposits by providing detailed three dimensional documentation of hydrofacies permeability, shape, and boundaries within an extraordinarily well exposed basin-fill sequence in the northern Rio Grande rift of New Mexico.