Dam No. 1, the largest, occupies a gap across the Dakota sandstone hogback, and ifs founded on Morrison shale and limestone and the Sundance sandstone. The abutments are Dakota sandstone and sale, and all the strata have about 15 degree dip downstream. The geology of Dam No. 2 is somewhat more complex. Due to sharp echelon folding, the hogback structure ends abruptly near dam No. 2 against a southward plunging anticline. The result is that the foundation strata dip to the southwest into the right abutment, with dips varying from 5 degrees on the right abutment to 70 degrees on the left abutment. The dam rests on upturned edges of the Morrison shale and limestone, Sundance sandstone and the Lykins formation. Dam No. 3 rests entirely on Lyons sandstone. Other Dams or Dikes which enclose Carter Lake: Carter Lake Dam No. 2, and Carter Lake Dam No. 3. |
