Estimated Altitude of the Consolidated Rock Surface Underlying Quaternary Sediments of the Wood River Valley aquifer system, South-Central Idaho

This dataset is the estimated altitude of the consolidated rock surface underlying Quaternary sediment of the Wood River Valley aquifer system. This surface is composed of the top of pre-Quaternary bedrock and Quaternary basalt, Wood River Valley, south-central Idaho. This surface was constructed using the depth of bedrock from about 1,000 well-driller reports for boreholes and about 70 Horizontal-to-Vertical Spectral Ratio (HVSR) ambient-noise measurements of the Wood River Valley aquifer system, south-central Idaho. Bedrock depths were subtracted from the altitude of land surface obtained from the 2009 1-Arc Second National Elevation Dataset and the resulting points were used to construct an estimated bedrock surface altitude with hand-drawn 100-ft contour interval. These contours were then used to create a raster surface of the estimate altitude of the bedrock surface as described in the procstep section below. This dataset was created in support of the third phase of a continuing U.S. Geological Survey (USGS) study to assess the groundwater resources of the Wood River Valley, south-central Idaho. The first phase was documented in "Water-resource trends and comparisons between partial development and October 2006 hydrologic conditions, Wood River Valley, south-central Idaho" (Skinner and others, 2007), and the second phase was documented in "Ground-water budgets for the Wood River Valley aquifer system, south-central Idaho"(Bartolino, 2009). The third phase is a description of the hydrogeologic framework of the Wood River Valley aquifer system. The Wood River Valley contains most of the population of Blaine County and the cities of Sun Valley, Ketchum, Hailey, and Bellevue. This mountain valley is underlain by the alluvial Wood River Valley aquifer system. The entire population of the area depends on groundwater for domestic supply and rapid population growth since the 1970s has caused concern about the long-term sustainability of the groundwater resource.

本数据集为伍德河谷含水层系统（Wood River Valley aquifer system）第四纪沉积物下伏固结岩面的估算高程。该岩面由爱达荷州中南部伍德河谷的前第四纪基岩顶面与第四纪玄武岩组成。该岩面的构建依托约1000份钻井钻探报告提供的基岩埋深数据，以及约70次针对爱达荷州中南部伍德河谷含水层系统的水平-垂直谱比（Horizontal-to-Vertical Spectral Ratio, HVSR）环境噪声测量结果。以2009年1弧秒国家高程数据集（1-Arc Second National Elevation Dataset）获取的地表高程减去基岩埋深，得到的采样点被用于以100英尺手绘等高距构建基岩面估算高程模型。随后按照下文procstep章节所述，利用这些等高线生成基岩面估算高程的栅格表面。本数据集的编制服务于美国地质调查局（U.S. Geological Survey, USGS）正在推进的第三阶段研究，该研究旨在评估爱达荷州中南部伍德河谷的地下水资源。第一阶段研究成果已刊载于《爱达荷州中南部伍德河谷部分开发阶段与2006年10月水文条件间的水资源趋势与对比》（Skinner等，2007），第二阶段研究成果则发表于《爱达荷州中南部伍德河谷含水层系统地下水均衡》（Bartolino，2009）。第三阶段研究聚焦于伍德河谷含水层系统的水文地质框架描述。伍德河谷涵盖了布莱恩县的绝大多数人口，以及太阳谷、凯彻姆、海利和贝尔维尤等城镇。该山间河谷的地下为冲积形成的伍德河谷含水层系统所覆盖。该区域所有人口的生活用水均依赖地下水，而自20世纪70年代以来的快速人口增长，已引发了人们对地下水资源长期可持续性的担忧。