The time line at the top of the page has the controls Zoom In, Zoom Out, and a drag bar that can move the time line. At first, only the earliest stages will be readable and the ones near the end will just be slivers of color. If you Zoom In several times, you’ll make the time periods at the end larger. The colored boxes with the names of the time periods are clickable and take you to that section. You could navigate that way, but it is far, far easier to use the drop down box at the top of the page.
The Earth’s time periods are (deep breath): Hadean, Archean, Proterozoic, Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene.
Whew! Some of them sound more like something you’d cough up than a time period. I don’t want to take away from your joy of discovery, so I’m only going to really pick apart the first one, the Hadean period.
The overview of the time period has links on a side menu called Contents that you can explore. In the overview area, you find out some specific characteristics of this period and an explanation for its name. If you scroll down the bottom of the overview you’ll find more links: Eon Overview (a link back to this page), Formation of the Earth, The Earth’s Atmosphere, and Earth’s Surface. You’ll also notice that those are the same links as under the Contents menu so it’s up to you which you use to navigate.
The Earth’s Surface section discusses what the Earth was made of at this time period, and let me tell you, it’s interesting to find out all about granite.
The Evidence section was my favorite part. Here you can check out a chunk of Meteorite that hit Arizona more than 50,000 years ago and some moon rocks!
Below all of this you’ll find a section in orange called Foundational Concepts. This is where you can learn about methods of dating the evidence displayed on the site as well as the time periods. You’ll learn all about the Earth’s Processes, from plates shifting to climates changing.
When you’re done with Hadean, you can move onto all the other time periods and watch as the Earth changes. Highlights would obviously be the Triassic, Jurassic, and Cretaceous periods when the dinosaurs roamed the Earth.
Take your time with this one, it’s a real gem!