Existing comment:
Greenland Lake -- Karst Topography -- Sinkholes
Geologically, the Kaibab Plateau is known as an area of karst topography. This plateau is capped with a relatively thick layer of water soluble rock, the Kaibab limestone. It allows easy passage of water into underground drainage systems. This results in an almost complete absence of surface streams.
The precipitation on the North Rim seeps through the limestone and eventually dissolves it. The underground solution chambers that result may collapse and form depressions or sinkholes. Soil and mud run off into these depressions, sealing the bottom, allowing the sink to hold water. Greenland Lake is one of many lakes on the Kaibab Plateau which are examples of this process. |