Ventifacts are sand-blasted rocks. They are typically faceted and often display parallel grooves carved by wind-blown sand. Ventifacts are common in desert environments where there is enough rocks and sand and little vegetation to keep the sand in place. Strong winds are also needed to lift and carry sand grains.
Dreikanter is a rock polished by wind-blown sand that has three faces. Width of the rock is 7 cm.
During my recent visit to California I visited a small hill or ridge in Death Valley which is covered with thousands of nice examples of ventifacts. Not surprisingly, this ridge is known as Ventifact Ridge. It was indeed very windy that day and there were lots of rocks and enough sand to blast them.
Well faceted ventifacts are called dreikanters (if there are three wind-blown faces) or sometimes zweikanters or einkanters (two and one faces, respectively). This is obviously German language which provides the prefixes ein, zwei, and drei. Ventifacts can be sometimes used to determine the dominant direction of wind. The direction of parallel grooves needs to be measured for that.
Ventifact Ridge does not seem to be among the important natural tourist attractions of Death Valley. It is just an ordinary hill and there are no signs pointing to it. Perhaps because the terms “ventifact” and “dreikanter” are virtually unheard of to the general public. However, geologically this is really interesting place which I recommend to visit if you have a plan to go to Death Valley.
This striated rock is much larger (width approximately 70 cm) example of ventifact.
Ventifacts often have more than one sand-blasted faces and sharp edges separating them. Width of the rock is about 60 cm.
These ventifacts are carved out of mafic vesicular volcanic rock. Width of the rock is 60 cm.
The whole ridge is covered with variously sized ventifacts. Amargosa Range with colorful rocks of the Artists Palette is in the background.