Winton is the dinosaur capital of Australia and the gateway to Australia’s Dinosaur Trail. It is centred on the Winton formation, a Cretaceous-age landscape that dates back about 100 million years. It was formed from sand and silt deposited by rivers and streams into a retreating inland sea.
Mesas around Winton are approximately the same height. This height represents the old surface some 30-20 million years ago. 50 million years ago this landscape was up to a kilometre higher than the present day. The Australian Age of Dinosaurs Museum is situated on The Jump-Up, a mesa which has been carved by water over millions of years. The landscape building continues today.
The blacksoil downs surrounding Winton are the weathered remnants of the ancient Winton Formation deposit. It is in these blacksoils that many dinosaur bones have been found including Elliot, Australia’s largest dinosaur.
Fossils are a part of our natural and geological heritage. The Australian Age of Dinosaurs Museum actively educates the public on the value, recovery, preservation and interpretation of many local fossils. They provide scientists with evidence about the history of life on earth and come in all forms and sizes. They can range in size from the tiniest pollen grain to the largest dinosaur bone.
How are fossils formed?
For a plant or animal to become a fossil, a series of events must occur. The remains have to be buried before they completely decompose or are eaten. The conditions of burial must then be suitable for the remains to leave an impression or have their organic material replaced by minerals. Finally, the fossils must survive millions of years of pressure, uplift and erosion if they are to come back to the surface. So what are the chances of any dead animal turning into a fossil? Many millions to one – so we must all appreciate the fossils that are found.
Step 1: A dinosaur dies and is buried before the remains are completely destroyed.
Step 2: Over time, layers of sediment build up and press down on the buried remains.
Step 3: Dissolved minerals, transported by ground-waters in the sediment, fill tiny spaces in the bones. The combination of pressure, chemical reactions and time eventually turns the sediments into rock and the bones into mineralised fossils.
Step 4: The fossils remain within the rock until uncovered by erosion or excavation.
Preparing Fossils
A fossil bone may now be mineralised ‘rock’ but it still has some similarities to modern bone. Bone has tiny lines on the surface, a dense outer layer and an inner spongy structure that resembles honeycomb. These can still be seen in fossil bone but not in rock.
The very early stages of piecing together the animals and plants of the past involve removing their fossils from the rock and preserving them for study. Different techniques are used to remove fossils from rocks depending on the properties of the rock and the composition of the fossils themselves.
Some rocks like mudstone or sandstone are soft so it is quite easy to remove the fossils using simple hand tools. Other rocks, such as limestone, are more difficult to excavate. In those cases chemical methods using acids might be used to remove some of the rock.
After the fossil bones are extracted from the rock matrix they are treated with special glues to preserve them and protect them from damage. Once the fossils are prepared and preserved, the laboratory at the Australian Age of Dinosaurs will study them in order to determine what type of dinosaur they belonged to and even what it looked like and how it lived.
Try this fun interactive dinosaur fossil dig...here
If you enjoyed this virtual dig you may like to join in a real dinosaur dig or help prepare fossils at this facility. Open hours at AAOD are 8.30am-5pm every day.
Geologists use fossils to perform environmental interpretation. Since certain ancient organisms either could only live in fresh water or could only live in ocean water, their presence in a rock layer reveals how the rock layer formed. For example, if a geologist wants to know whether a layer of sandstone formed on an ocean bed or ended up there long after it formed in fresh water, the geologist can look at the type of fossils in the sandstone for an answer.
Look around at the wonderful and contrasting landscapes before you and take a moment to appreciate them. You are standing on the very same earth that held up the mighty dinosaurs nearly 100 million years ago. One day, you too, may be a fossil and be marvelled at by someone (or something) else.
You may log this Earthcache straight away but then please email your answers to the questions to the CO. We will contact you ONLY if your answers need extra work. Logs with no answers sent will be deleted.
Use the many information boards and displays (and perhaps some research) to answer the questions. Remember to take only photos and leave no trace of your visit. Enjoy your time with the dinosaurs.
Q1. What is a fossil?
Q2.What is special about the blacksoils the fossils have been found in?
Q3. What type of dinosaur fossil is Banjo?
Q4. How are the fossils protected before moving them from the field to the laboratory?
Q5. The fossils on display in the collection room are kept in a climate-controlled environment. What temperature are they kept at?
Q6. What is an index fossil? Name one.
Q7. Name at least one hand tool used to prepare a fossil for study?
You are welcome to post a photo of yourself enjoying this earthcache. No spoilers please.