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Digging for Dino Bones
North America was home to some pretty amazing animals during the Cretaceous Period,
(144 – 65 mya). The rocks you are standing on are from the Cretaceous Period! 144 mya
this area would have looked differently because the climate was completely different.
Most of what would some day be the United States was covered in a shallow sea. New
Mexico was home to some very interesting animals. Meet the Bisti Beast. Also known
as Tyrannosauroid. Just the head was about 40 inches long.
This station is a field of dinosaur “bones”. Use the Dinosaurs from the United States
charts to identify the “bones” you excavate. Please follow the excavation procedure
below.
Read all directions before beginning the activity. You will need 4 flags, about 2 yards (6
feet) of string and the excavation brushes.
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Spread out and locate the fossilized remains of a dinosaur.
Please select only one site per group to excavate.
When a bone has been located, set the flags in a square around the dig site.
Carefully sweep away the soil using the excavation brushes.
When a “bone” has been completely unearthed, lay it out on a clipboard.
As each new “bone” is unearthed, lay it out on the clipboard.
Arrange the “bones” to identify the shape of the remains of the dinosaur.
Use the Dinosaurs from the United States charts to identify the “bones” you
excavate.
9. Use the tape to assemble the remains and leave them inside the flagged area.
10. Tie the string to the 4 flags to protect the dig site.
Take a few minutes to sit and look around the area. Try to imagine a much wetter
climate. Imagine large dinosaurs and tall trees, giant ferns and scurrying water creatures.
The climate changes and these creatures cannot adapt. One by one they are buried in the
drying mud. Millions of years pass and the once tropical landscape is buried by layers of
sediment, lots and lots of sediment. Shiprock would have been underground as it is a
volcanic plug. Volcanic plugs are formed when magma is forced up through an opening
in the earth. The magma cools before escaping so it takes the shape of the opening in the
earth. The earth erodes away and here we are again. By the looks of it, this Cretaceous
rock won’t last much longer. Look at all that erosion!
Don’t rush off! A good Paleontologist is always patient. Take another quiet minute and
let the earth talk to you. This is a good place to write a little poem about Hogback in
your journal.
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