This Story Rocks
By Laura Deering
Rockport-Quarry, Lake Huron Shoreline (Laura Deering).
We’re off to the sea! Yes, the briny salty sea. Pack your sunscreen and a bucket for all our beachcombing finds. Oh, don’t forget your hammer, safety glasses, and sturdy footwear. Flip flops just won’t do, as we will be hunting wild, weird, and wonderful things at a fossilized sea.
Thankfully, my friend Kelly took on the above “pitch” to go fossil searching with me at Rockport Quarry Recreational Park, near Alpena, Michigan. This former limestone quarry turned recreation area is chock-full of sights and activities: the stunning Lake Huron shoreline, sinkholes, shipwrecks, and 300 acres for fossil hounding to your heart’s content.
OJUP/Shutterstock.com.
Rockport Quarry
A critical point of interest is being able to look and take home the fossils you find. That’s right, Rockport Quarry Recreational Park has rolled out the yellow brick road. It is “finders keepers,” meaning you get to keep the fossils—within the state limit of 25 pounds of rock per person, per year. The number of places in the United States that allow this is quite a short list. Many other countries completely prohibit this activity, even if you own the land.
Another plus for Rockport Quarry is that it’s off the radar. In fact, we had the entire quarry to ourselves. About the only thing we were tripping over were fossils, fossils, and more fossils. The further we progressed, the more exotic the finds became. We barely scraped the surface, with over 200 species of fossils to discover in the quarry. Before getting too far ahead of ourselves, let’s learn more about this sea, as we skip, stroll, and meander to find hexagenerians (Petoskey stones), stromatoporiods (sponges), and gastropods (snails)—oh my!
Illustration of Dunkleosteus terrelli, an extinct apex predator from the Late Devonian period (Prehistorica). Trilobite fossil (Mark Higgins/Shutterstock.com). Petoskey stone (Alyson Williams/Shutterstock.com).
Michigan’s coral reef
While Michigan conjures up winter scenes of snow and ice, the Alpena area was once a tropical inland sea. A coral barrier reef teemed with marine life of sponges, sea lilies, and snails, with the occasional 30-foot fish cruising the scene. Welcome to the Devonian period some 360 to 410 million years ago. Here lie hex-shaped corals ranging from fist to basketball size, which fossilized into Michigan’s state stone, the Petoskey. The Devonian period is considered the “age of the fishes,” and the quarry has unusual specimens of armored fish fossils, as well as rare trilobites, one of my favorite fossils.
Treasure map
While we thought it would be obvious how to find the quarry, once inside the park, it was not intuitive. We parked at the edge of the Lake Huron shoreline, where the old freighter pier remains, and admired the view. However, the quarry was not visible nor was there any signage directing us to it. Near the shore was a small mountain pile of rocks. As tempting as it was to climb the pile, the heat of summer made us pause and consider our next steps.
Both of us plotted our strategy. Being small-town residents, we decided to head back to the main highway and chat with the locals. Luckily, our first encounter hit pay dirt, providing us with a treasure map written on the back of a cigarette carton. Woohoo, off we bounded, not wanting to lose one second of 410 million years in the making.
Scenes from Rockport Quarry Park and Petoskey stone embedded in rock (Laura Deering).
Fossil quarry
Returning to the same parking lot, this time we walked in the opposite direction from Lake Huron and passed by an unlocked swing-gate that led to a single-lane, narrow, yellow sandy road. Just as the treasure map noted, within 10 minutes, we started recognizing a difference in terrain. Here, the ground went from sand to hard brittle slate-colored rock. Another thing was the heat—there was no cool lake breeze to offset the sun blazing off the rock.
The road once was the old, narrow-gauge railroad, which hauled crushed limestone to the Lake Huron pier to be loaded on freighter ships. Visible alongside the road are piles of crushed limestone about six feet high and eight feet wide, referred to as “bell” piles. Resembling huge loaves of bread, they provided excellent rummaging for small fossils, such as tiny coral branches, itsy bitsy crinoids, and wee brachiopods. Thanks to the crushing of the limestone from the mining years ago, it was easy pickings. Fingers and a sharp eye were all we needed to explore this darling miniature world of fossils, making it a great introductory place to start and perfect for all ages.
Petoskey stone and horn coral fossils. Shell fossil embedded in rock. Stromatoporoid fossil. (Laura Deering).
Fossils on top of Fossils
After perusing the bells, we started spotting larger fossils in the bedrock beneath our feet. Excited, we chiseled a few and tossed them in the bucket. The further we ventured, the more abundant and bigger the fossils. It occurred to me: we were walking on top of the ancient sea—how marvelous it felt. Compared to other fossil forays often on the edge of an active ocean or lake shore, there were no worries of tide tables, unstable cliffs, or the next wave stealing back our epic fossil find. One could wander in any direction with endless choices of relics to choose from.
After a while, I learned to look for large boulders loaded with colonies of various coral species. Instead of the hammer, I would use my fingers to gently jiggle out layers of fossils and examine each frame. Doing this technique was like reading a page-turning mystery novel; what was going to turn up next? Sometimes a remnant, like a horn fossil compressed from all the years of layers and pressure, made positive identification a challenge. However, soon another intact specimen was usually found.
Petoskey stones
Within another hour, other wonders unfolded. Admiring the landscape of lake-hardened birch with comrades of wildflowers, it was astounding to see nature make a rebound after sixty years of mining. The flowers seemed to shout, “Forget that ancient sea lily, admire me.” Soon we paused to take a photo of a sentinel birch tree with an oddly shaped branch. The branch had been pointing the whole time as if to say, “Here! Look here!” Well, maybe I was getting dehydrated and hearing voices, except there was an amazing find at the foot of the tree.
There laid a delightful Petoskey stone, uniform in shape and condition. All it took was coaxing the hammer with gentle taps. Even the stone seemed ready for its next adventure, and prying it with our hands set it free. The fossil turned out to be a great learning aid for Kelly’s science class—she’s a teacher in Michigan.
Possible trilobite fossil (Laura Deering).
Encouraged by the spectacular find, we shifted our sights towards the north to see if we could find more Petoskeys. And we were curious to see the enormous pit shown in photos of the quarry. After about 15 minutes of walking, the pit started to appear. And our hopes replenished.
Except, after another 15 minutes, now panting, the pit remained off in the distance. This is when the magnitude struck us. Its size and depth of possibilities were humbling and daunting. Recognizing this, we agreed another adventure lay in store.
Tips
On our way back to the car, we discussed plans for our future foray:
- Bring gloves.
- Carefully decide which fossils are of most interest (as you have to carry them out and, in my situation, fit them in a suitcase).
- Since the features of the quarry are similar, having objects to mark your way back to the main path is important.
- The bottom line: You will find fossils. And you get to keep them.
Learn more about beach fossil finds from around the world. Articles ›
This article appeared in Beachcombing Magazine Volume 41 March/April 2024.
