Old Rock is a fictional story that could be set anywhere. It doesn’t say where Old Rock lives in the book, but since I live in Michigan,
I imagined Old Rock to have ended up in one of my favorite places: The west side of Michigan’s lower peninsula, overlooking Lake Michigan. I wanted Old Rock’s story to be plausible, so I learned about rocks and earth’s natural history by reading books, visiting a museum, going online, and talking to experts, including a geologist, an evolutionary biologist, and a paleobotanist. Here is some of the information I learned with links to resources about the time periods and characters in the story.

Old Rock        

There are three types of rock: igneous, metamorphic and sedimentary.
Old Rock is a metamorphic rock. Metamorphic rocks are formed under the earth with extreme heat and pressure. It can take a really long time for a metamorphic rock to form — millions of years! At first, I thought Old Rock might start the story as a blob of lava, but then decided against it because the type of rock that forms from hardened lava was not right for Old Rock. 
I chose a kind of rock called gneiss, because it’s metamorphic, has a nice texture, and sounds like the word “nice.”



I really wanted Old Rock to fly, both because we think of rocks as being stationary and immovable AND because it would make a dramatic start to OLD ROCK’s story.  Being ejected during a volcanic eruption seemed to be a perfect way to make Old Rock fly. There was a great amount of volcanic activity at different periods in the earth’s history. Old Rock was blasted into the sky 300 million years ago during a pyroclastic eruption. 

Geological periods
The earth is approximately 4.5 billion years old. Old Rock was formed 1.8 billion years ago during the Proterzoic eon, well before the time period where dinosaurs roamed. Old Rock is ancient! The next time you pick up a rock, try to imagine how it was formed and where it came from.

To learn more about the geological time scale:

Old Rock was around during the “age of dinosaurs,” and met a Tyrannosaurus rex and a Brachiosaurus, and probably many others. What is your favorite kind of dinosaur

(Michigan note: Dinosaurs most likely lived in Michigan, however, dinosaur fossils have not been discovered because the sediments eroded before any remains could fossilize. https://www.thoughtco.com/dinosaurs-and-prehistoric-animals-of-michigan-1092080 )


Mastodons roamed North America for almost 24 million years until their extinction 10,000 years ago. Mastodon remains have been found in several locations in Michigan, including someone’s backyard. Do you think there are any fossils in your neighborhood?

(Michigan note: Mastodon is the state fossil of Michigan)


Have you ever seen a big rock sitting alone in a field or forest and wonder how it got there? Chances are it was deposited by a glacier. There were several ice ages during the history of our planet. The last one ended 11,500 years ago. Check out this video simulation of glacial action for the Laurentide ice sheet — the glacier that left Old Rock perched on a ledge and formed The Great Lakes.

Old Rock traveled for a long time in that glacier. On and off for over 2.5 million years. Glaciers move very slowly. How many miles do you think Old Rock traveled?

Spotted Beetle 

Spotted Beetle is what we commonly call a ladybug, a small brightly colored beetle found widely in Michigan and throughout the world.

Tall Pine
Michigan is home to many pine trees and evergreens. I wanted Tall Pine to be a White Pine because there is a large White Pine tree outside my office window where I wrote and illustrated Old Rock.  

(Michigan note: White Pine is the state tree of Michigan.)

Hummingbird is a Ruby Throated Hummingbird. Most Ruby-throated Hummingbirds spend the winter in Central America and then fly north in the spring. Some travel all the way to the northern edge of the United States and Canada. A hummingbird’s wings flap so quickly they are hard to see.— Up to 53 times a second! How many times can you flap your arms in a second? How about a minute?

To learn more

Visit your local library and check the non-fiction aisles for more about
rocks, volcanoes, dinosaurs and glaciers.

Visit a museum! I learned about Mastodons and prehistoric periods at
the University of Michigan Museum of Natural History.