How were dinosaur tracks formed?130 million years ago, during the Late Cretaceous period, the landscape where dinosaurs travelled was very different from how it is today. The Australian landmass was separating from Gondwana — the massive super-continent that included Antarctica, India, South America and Africa. Summer and winter were more pronounced, although the temperature never dropped below freezing. Towering conifer forests covered much of Australia and smaller plants such as ferns and gingkoes created an understorey. The first flowering plants (angiosperms) were evolving. The combined effect of new plant life in a cool and temperate climate provided an ideal landscape for dinosaurs.
The dinosaur tracks on the Dampier Peninsula were made as animals trudged through what was then a vast ancient river plain that opened into a wide belt of tidal deltas, brackish lagoons and estuaries, crisscrossed by channels and creeks. Cycad fossils found in same platforms as the dinosaur tracks give us clues to the ancient plants that existed then.
Tracks were made when dinosaurs stepped into the soft muddy sediments of the river deltas, leaving indentations in their wake. Left undisturbed, a blanket of dry sediment gradually covered the tracks and helped to protect them. Over time the sediment hardened by a process of lithification — the compaction and bonding of sedimentary grains through chemical/mineral reactions. When the sediment finally turned into rock, the tracks were preserved in the nearly horizontal layers of cross bedded reddish sandstone and siltstones (now called the Broome Sandstone). In some places the receding water movements have also been preserved – there are ‘rippled’ sandstone layers that show the direction water moved.
Even the hardest of rock can be worn down by erosion and weathering over time and eventually, the layers of sediment covering the fossil tracks were worn away to reveal the indentation of the original footprints.
Becoming a Dinosaur Tracker
Dinosaur tracks are a precious resource that can be easily damaged. Viewing them is a privilege that is not granted to everyone. Visitors must take care not only to leave the tracks undamaged, but to ensure they themselves return safely from their adventure.
Most of the tracks occur below the high water mark and shifting sand often covers them up. Remember this is a dynamic landscape where nothing is certain — tracks may get buried or destroyed by pounding surf. Beaches here are subject to some of the most extreme tides in Australia, with water levels rising up to 10m on spring tides, so many sites are only exposed for a few hours each day or a few days a year. Plan your trip accordingly. You need to be aware of the tides, weather conditions and the time the sun goes down. If you can, visit a beach regularly and be alert to the changes in rock exposure. As a rule of thumb sites can only be visited when the tide is 2.5 metres or lower.
Becoming a dinosaur tracker also requires good shoes that protect feet from sharp surfaces and won’t slip on wet rocks, a hat, sunscreen, plenty of water and a mobile phone to use in case of accidents or emergencies.
Enjoy tracking – it is your chance to go back in time to 130 million years ago.
Where to look
Gantheaume Point is the most well known place to view tracks but it is not recommended unless you are fit and fast as the rock ledges that contain the tracks are only accessible at extremely low tides and after climbing on slippery rocks. There are other locations around Broome where you can view dinosaur tracks with less risk – these have been included in a leaflet put out by the Dinosaur Coast Management Group.
For more information on how to find and identify tracks, download the leaflet here. Download
If you have time to spend looking, tracks may be found on the exposed sandstone rocks, shelves and reefs in the intertidal zone of most beaches near to Broome. Some places to try include:
- Entrance Point is easily accessible. There are many sauropod tracks on the rock platforms. Walk west looking at the rock platforms, including round the first corner.
- Maralagun on Cable Beach below the Cable Beach Club has easily accessible rock platforms with theropod and sauropod tracks, although they are often covered with sand. It is also an important cultural site.
- Yinara – Reddell Point and Reddell Beach south has theropod and sauropod tracks. Access is via Kavite road which may be closed in the wet season and sandy in the dry. Alternatively it’s a long but spectacular walk from Entrance Point.
- Gulbanwila near the Broome Bird Observatory and the boat ramp has a well preserved sauropod platform. See the photo below. Check out the new signage at the boat ramp.
As a general rule, if you measure the width of any print then multiply it by 4, this is will give you an idea of the height of that dinosaur to the top of its hip!The type of tracks most likely to be encountered are the large cylindrical depressions stamped into the earth by four-legged, plant-eating, long-necked, long-tailed sauropods. Some tracks have formed deep impressions in the sandstone where the displaced mud at the edge of the print is clearly visible. Sometimes ‘toes’ can be distinguished. Others are weathered and only appear as shallow, circular underprints. Smaller tracks may have been made by the smaller front feet of adults or by sub-adult animals.
The Dinosaur Coast sauropod tracks are the only ones found in Australia. Some of the depressions measure longer than 1.5metres .. huge tracks, probably made by creatures more than 30 metres long .. some of the biggest dinosaurs ever to have walked on the planet.
Terminology – get it right!
In current scientific conversations the prints left by the feet of dinosaurs as they moved across country are called TRACKS, not footprints. Such tracks may be preserved in isolation or in association with others. A sequence of tracks made by a single trackmaker is called a TRACKWAY. A concentration of tracks, either of trackways, multiple isolated tracks, or a combination of both tracks and trackways, is referred to as a TRACKSITE.