Permeable lenses of sand and gravel within till
![Photograph showing unconsolidated deposits in North Dakota.](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/thumbnails/image/i029nocap.gif?itok=0IPRuALm)
Detailed Description
Permeable lenses of sand and gravel within till show a wide variation in bed thickness, grain size, and sorting of grains. Photograph showing unconsolidated deposits in North Dakota.
Sources/Usage
Public Domain.