The beautifully patterned sandstone rocks exposed along the shore were caused by groundwater percolating down through the porous sandstone rocks and leaving traces of iron oxides. The formation is carved out by sea wave action. The regular patterns of red, orange, and yellow bands and rings are due to fractures, joints, and layers present within the sandstone.
The entire island and the ocean around the painted rock is a national park full of birds, animals, and marine life. Apart from the painted patterns, rocks here are weathered by salt crystals from sea spray, which has created a beautiful honeycomb pattern. Fragments of salt crystals worn by the water gradually make small potholes and notches into the surrounding cliff.
Tasmania’s coastline has rugged and spectacular topography, With unique and fascinating geology, Maria Island is a top destination for the geologist. The cliffs are accessed when a low tide and the sea is showing calmness, the tidal pools surrounding them make for an excellent snorkeling place. The cliffs are beautiful and intriguing, during midday, but come fully attractive on a sunny afternoon when the evening light strikes the pale sandstone, warming it in golden colors and creating a photographer’s paradise.
The sediments deposited here came from two prominent hills known as Bishop and Clerk and Mt. Maria, located at the upper point of Maria Island. The iron oxide patterning was deposited much more recently, within the last 10 million years, when Tasmania was experiencing a monsoonal climate. Rainfall events leached out iron from the dolerite rocks above the sandstone, seeping into the softer rock. The monsoonal phase was then followed by periods of extreme dryness, which drew the water back to the surface, leaving the iron oxide stained behind to be eroded and exposed by rising sea levels to reveal the patterns.
According to the Internet