Geologic Map of the Scotts Mills, Silverton, and Stayton Northeast 7.5 Minute Quadrangles, Northwest Oregon: A Digital Database: Silverton Quadrangle

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits of the Silverton 7.5 minute quadrangle along the eastern margin of the Willamette Valley and adjacent lower foothills (Waldo and Silverton Hills) of the Cascade Range. The major emphasis of this investigation was to identify and map Columbia River Basalt Group (CRBG) units and to utilize this detailed CRBG stratigraphy to identify and characterize structural features. Together with the accompanying text file (geol.txt or geol.ps), it provides current information on the geologic structure and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The scale of the source maps limits the spatial resolution (scale) of the database to 1:24.000 or smaller.

本数字地图数据库整合了既往已发表与未发表的数据，以及作者团队完成的最新测绘成果，完整呈现了威拉米特谷（Willamette Valley）东缘及喀斯喀特山脉（Cascade Range）毗邻低山麓（沃尔多丘陵与锡尔弗顿丘陵）范围内，锡尔弗顿7.5分钟地形图分幅区域的基岩与表层沉积物总体分布情况。本研究的核心重点为识别并测绘哥伦比亚河玄武岩群（Columbia River Basalt Group, CRBG）地层单元，并借助该精细的CRBG地层学信息，识别并解析区域构造特征。本数据库与配套文本文件（geol.txt 或 geol.ps）共同提供了研究覆盖区域内当前的地质构造与地层学相关资料。本数据库依据美国地质调查局（U.S. Geological Survey, USGS）的地层命名规范，按照大致年代与岩性对地图单元进行划定与标注。源地图的比例尺将本数据库的空间分辨率（比例尺）限定为1:24000或更小。