Deep time happening under our feet
When we go walking at Munibung Hill, we are in the presence of a geological history dating back 251 million years. The conglomerate we are walking over, as shown in the above picture, is made up of several pebbly conglomerate beds interspersed by sandstones.
One of the five rock types that make up Munibung Hill, it is a sandstone associated with the Teralba Conglomerate:
It shows its fluvial (riverine) origin in several spots where flow point deposits (wedge shapes, from sand deposits under flowing water) can be seen. On the northern shoulder of the upper steep section, there is a nice little conglomerate bed exposed. Immediately above this sandstone is a coal outcrop – not easily visible except for a dark grey fan where the coal has washed out.