Minnesota PaleoWeb: Collecting in Minnesota
Minnesota PaleoWeb > Collecting in Minnesota
The following equipment is helpful for a productive fossil collecting trip:
- Backpack
- Hiking boots
- A good hat
- Sunscreen & insect repellent
- First aid kit
- Geologist's or bricklayer's hammer (available at most hardware stores, don't spend
money on over-priced mail order offers or specialty shops)
- Chisel
- Protective goggles (even if you never use them, you really ought to)
- Magnifying lens
- Labels and pencils for identifying fossils
- Plastic bags (zip-loc work well) for storage
- Containers with cotton to store delicate finds
- Detailed roadmaps. Consider the Minnesota Atlas & Gazetteer by Delorme, ISBN: 0899333338
- Snacks and beverages
I've also found it useful to bring a handheld GPS unit for marking
general location. The dedicated hobbyist can then go to
TerraServer
with the coordinates and view an aerial photograph or topographical map of
the region. Accuracy of GPS is good for general location, but not
accurate to the precise geological layer or formation you remove the fossil
from. So take note of this also -- don't just rely on your GPS. Also, I've found
that the higher-end GPS units with roadmaps simply don't offer the topographical and
geographic details useful for a fossil hunting trip. So a lower-end model gets the
same job done.
A digital camera and a 35mm camera with good tripod is a nice addition.
I didn't want to skimp on the tripod, so I bought a fancy and stable
Bogen from a camera shop. You might find that a $500 digital camera,
$300 35mm camera, $150 tripod, and $300 GPS unit adds up. They're not
necessary, but if you already have them just pack them along for your
expedition. These sometimes become daylong adventures (or longer) -- and
you may find that your digital camera and GPS batteries give out before you do.
Therefore, a good 35mm and compass remain useful additions to (or substitutes on)
your equipment list.
The following rules should be observed while collecting:
- Obtain permission before entering private property. Call a city or county
office to determine the current owner. Though my personal take on it is that everything
is quickly becoming a minimall, so it's best to excavate fossils quickly before they're all buried under asphalt. The far past belongs to everyone, not a handful of land developers.
- Be careful! Quarries and roadcuts are not safe. Loose rock, animals, barb
wire fences, bad weather, wood ticks, poison ivy, and other hazards can be expected.
Also, I get nervous hunting for fossils during hunting season. Use your best judgement.
- Fossils from a specific time period are a non-renewable resource. Collect only
what you need. Don't try to get everything or sell them for cash. You can make more
money elsewhere. Make it a point to leave some for the next generation.
- Document your finds -- you may one day donate them to a museum or pass them on to your
children. Each fossil should include the collector's name, date found, location where it
was found, geological layer (Decorah Shale, etc.), identification, and notes. It's easy
for fossils to become separated from their labels. So consider photographing them,
sketching them, or describing them -- so you can maintain proper reference between label
and fossil should they become separated. Another possibility is to use white ink to
mark the fossil with an accession number. This isn't practical on smaller fossils, or
over highly corrugated rock surfaces.
- Bring unusual or rare finds to the attention of an expert. Don't try to remove them
yourself. There aren't many experts in this field, and probably none with the
time to travel, but at the very least make a good faith effort. A clear photograph might
be useful as well.
For a color map of Minnesota bedrock exposures:
Minnesota Geological Survey.
To see where North America was situated on the globe in the far past:
Dr. Ron Blakey's site at Northern Arizona University.
Identifying fossils commonly found in Minnesota:
Check out my list of regional organizations
and print guides here:
http://www.tc.umn.edu/~brams006/mnpaleo/resources.html.
Below is a list of noted localities in Minnesota to search for fossils. I've included comments on the accessibility and content of each site:
Shadow Falls:
On the Mississippi River bluffs at the end of Summit Ave. in St. Paul
Formations to check:
Platteville Limestone and Decorah Shale
Comments:
Look especially in the Decorah Shale, a greenish to biege flaking clay-like layer. You'll find bryozoans, crinoid columnals, brachipods, and occasional gastropods. For the more adventurous, there are trails leading up and down the river bluffs. An exposure of white St. Peter sandstone is found closer down to the river and slightly to the south.
Hidden Falls Park:
Off Ford Motor Parkway, near the Ford Motor Plant in St. Paul
Formations to check: Platteville Limestone
Comments: I haven't scouted this site very well, and was unable to find a Decorah Shale layer here. This may be a place to check for imprints of brachipods and corals in the Platteville Limestone formation.
Sogn Roadcut:
Locate the intersection of Goodhue County 9 and Highway 56. Go north on Highway 56 and
look to your right (east side) for the next quarter mile.
Formations to check: Decorah Shale
Comments: This is one of the most accessible places to search in Minnesota. Many bryozoans, brachipods, and gastropods. Some cephalopods and
occasional trilobite parts. Search the limestone rocks found within the Decorah
Shale layer for larger fossils. Less known by collectors, and further out of the Twin Cities, there are good finds to be had here.
Lilydale Regional Park:
The "Brickyards Area". Exit on Lilydale Road west of Highway 35E in St. Paul, immediately south of the Mississippi.
Formations to check: Platteville Limestone and Decorah Shale
Comments: This area is dangerous -- don't go here alone and watch children carefully. Falling rock, cliffs, and slippery slopes can be hazardous. The caves are man-made, contain no fossils, and are off-limits. Hike to the clay pits and you'll find a wealth of bryozoans. Occasional good finds are to be had here, especially in the spring when a new layer of material is exposed by melting snow. Wear good hiking boots and prepare to get muddy.
Cherokee Heights Regional Park:
South of St. Paul.
Formations to check: Decorah Shale
Comments: This area is really a continuation of the "Brickyards Area" of Lilydale Regional Park. Start at a parking lot and take one of the steep trails down the bluffs. As you go down the trails, limestone with imbedded fossils begin to appear. There's also a stream gulch that cuts through both Platteville and Decorah layers worth exploring. Be prepared for strenuous climbing over logs, through mud, and up ravines if you attempt it.