The Magic School Bus In the Time of the Dinosaurs to after he fought the T-Rex; which made Arnold leave the sneaker footprint from his shoe due to his giant size). When Ms. Frizzle says she wonders what giant creature left that footprint, this is what Carlos says in response. Carlos says "I'd say it was a 'Sneakersaurus'!". Ms. Frizzle is missing some photographs from her photo album of her last trip to the age of dinosaurs. As usual, the user has to find replacements. There are seven different places, including "Triassic Arizona", "Triassic Argentina", "Jurassic Colorado", "Jurassic Tethys Sea", "Jurassic Tanzania", "Cretaceous Alberta", and "Cretaceous Mongolia". Here in the
Geological period example the 'Jurassic System' of rocks was formed during the 'Jurassic Period' (between 201 and 145 million years ago). The following table includes all currently recognized periods. The table omits the time before 2500 million years ago, which is not divided into periods. See Geologic time scale#Proposed Precambrian timeline for another set of periods 4600–541 MYA. In a steady effort ongoing since 1974, the International Commission on Stratigraphy has been working to correlate the world's local stratigraphic record into one uniform planet-wide benchmarked system. American geologists have long considered the Mississippian and Pennsylvanian to be periods in their own right