This road cutting has revealed gently inclined layers of sedimentary rock from the Triassic Period. The sediments making up these rocks were deposited about 220 million years ago. Thus it is also possible to say that fossils in these rocks must be the remains of things that lived (and died, and were covered) at the time the sediments were deposited. Note that most fossilisation takes place under watery conditions. 

While considerable weathering of these relatively soft sedimentary beds has taken place, it is possible to identify strata best suitable to fossil collecting. Suitable layers meet the conditions of fine-grained, layered, sedimentary rock. Note though, that all rocks meeting these conditions do not necessarily contain fossils. It is also required that past environmental conditions were able to support life that suited fossilisation.

Please note that safety procedures must be followed when collecting on slopes. 

The shale beds are lightly jointed to give a 'blocky' appearance (above) when loose materials are scraped away. These blocks can be split to produce smaller blocks, which then are carefully split parallel to layers. Plant impressions are common here. Whole leaves and fronds, and fragments of twigs and branches are reasonably easy to find. However, patience is needed to find complete specimens. Because the shale is soft, it is necessary to transport fragments carefully. 

The rock hammer shown has a chisel end for splitting fossil-bearing rock layers (rather than a point, which causes such specimens to fracture). Necessary equipment can be obtained from educational suppliers and rock/gemstone shops.  

Please note that students and teachers using rock hammers to collect fossils must wear eye protection (safety goggles are recommended).

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Some of the results of careful searching in the fine-grained sedimentary layers are shown above. A reading of the literature indicates that the rocks (and hence the fossils) of this area formed about 220 million years ago. 

Sediments from nearby mountains were deposited upon the older meta-sedimentary basement. Rivers wound their ways across flood plains and deposited fine sediments - plant remains were trapped (and fossilised) in these materials. In places there was lush vegetation in swamps and bogs. Shale, mudstone, siltstone and coal formed across wide bands of what is now the Brisbane - Ipswich area. Today, these Triassic (and later) sedimentary beds are generally found in areas of lower elevation between igneous and metamorphic hills of greater age. 

Thus, within the environs of Brisbane it is possible to study a wide variety of rocks and landscapes developed upon them. The three major types (igneous, sedimentary, and metamorphic) are represented. It is possible to find fossils, and to view features that originated from a wide variety of landform-building environments, including a deep sea trench, in river flood plains and swamps, from violent volcanic eruptions, and igneous intrusions and associated re-metamorphosed rock .     

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