This EarthCache aims to teach visitors about the process of erosion, the formation of rills, and the impact of water on cliff faces.
Logging Requirements: To log this EarthCache, please submit:
- What material is the cliff face made of? How do you think the composition of the cliff affects the formation of rills?
- Examine the cliff face and identify the erosion rills. Note their size, depth, and the pattern in which they are formed?
- Provide a photo evidence of your visit.
Geological Information:
Moonta Bay cliff consists of a soft calcareous loess (fine wind blown sand deposits) formed in a sand dune. The base of the dune is a soft pale orange calcareous rock. The exposed section, around 8 metres high, at this earth cache shows dramatic erosion damage.
Erosion rills are small channels cut into the cliff face by the persistent action of water runoff. These features provide a fascinating glimpse into the processes that shape our landscape over time. By studying these rills, we can understand the impact of water erosion and the geological history of the area.
Erosion rills are typically formed in soft rock or sediment that is easily eroded by water. The process begins with rainwater running down the cliff face, carrying small particles away. Over time, these small channels deepen and widen, creating the rills you see today. The pattern and formation of these rills can tell us a lot about past weather conditions and the durability of the rock.
Safety Note: Be cautious when near the base of the cliff as material, i.e. stones and rocks, may fall from the surface.