Extent of Pliocene hyaloclastic deposits and related lava flows in the Columbia Gorge, Oregon and Washington

This dataset contains polygons representing deposits of hyaloclastic debris that were generated between about 3.5 and 3.0 million years ago when a series of basaltic...本数据集包含若干多边形矢量要素，用以表征约350万至300万年前形成的玻屑碎屑（hyaloclastic debris）沉积物，该类沉积物生成于一系列玄武质（basaltic）...