Directions to the site:
Take Road 274. Turn onto unmarked road at N 37° 20.065 W 119° 34.310. There is parking along the roadside or down in the day use area. Follow trail to the posted coordinates.
At the posted coordinates is an excellent example of a rock-cut basin.
Rock-cut basins are cylindrical depressions cut into stream or river beds, often filled with water. These basins are formed when fast running water currents cause small stones to move in a circular motion, similar to a vortex. As the stone spins and makes contact with the riverbed/streambed, it causes a physical abrasion. This effect erodes the natural rock substrate to create concavities. This phenomenon is called a "kolk". As the motion continues, these holes increase in depth and circumference. One or more these small stones may be found within them. Also, depending on the flow of the water and size of the small stone, the depressions formed can vary in size.
To log this as found, please e-mail me the answers to the following questions. Do not post the answers in your log. A picture of you with your GPS would be much appreciated but not required.
Questions:
Approximate depth and width of largest hole?
Average size of the small stones inside the holes.
How do you think these holes were formed?