Baculite Mesa

Recently I was invited out to Baculite Mesa, CO, to go play around in the clays and sandstones with my alma mater and the new class of budding geoscientist. The location was on private property but thanks to the college professor arrangements to dig on the property were easily arranged. 

As a side note:  A lot of the fossils we found can be located 2miles or so East of  I-25 in Pueblo but there is a lot of farm and private property so pay attention to no trespassing signs.

For the dig site we were at you can use your hands to dig in the regolith and soils.  Gloves are needed, but a spade(shovel) or a small rock pick are a nice advantage.  Having been to the location before I knew I wanted a pic to break up some of the larger conglomerates.

My new rock pick is actually a 22 inch concrete buster found at my local hardware store for a little under $30.

 What we were looking for is what the mesa is famous for, Baculites.  Known as walking stick rocks, or those funny little elongated ovals found in dirt to amazed kids playing in mud.  Bacluites are actually ammonites with nearly straight shells.  They are similar to oval cones if your ever lucky to find one whole.  They are in the Molusk

The two I was happy to keep.

Baculites are found in the Mesozoic Era, specifically  the Late Cretaceous period.  The earth was warm and tropical.

This Baculite is just over 3 inches in length. The pattern on the right of the Baculite is called sutures.

 In the above picture you can see sutures on the rock.  Sutures are the walls of the different chambers of the baculite.  Different sections of its segmented body. In the picture below you can see the telltale signs of the baculite, the oval shape of its bodies width.

Width just over 1 1/8 inch.

 Sometimes when finding baculites you will be lucky to find one with the nacre still attached.  The nacre is the baculites shell.  In the pictures below there is a yellowish/white surface chipped and broken along the fossil.  This is the nacre.  As you can see this fossil is very simular to the one above.  They are both baculites the following just has portions of its shell.  It is also a little smaller in measurements.  But a great find none-the-less because it has a portion of its nacre.

That is not all you can find in the Mesozoic.  I was lucky enough to find numerous bivalves and brachipods.  So yeah there are seashells in geology in the plains of Colorado. The difference between a bivalve and a brachiopod is very slight.  Brachiopods have had valves (shells) on the uper and lower surfaces, unlike the left and right arrangements in bivalves.  This is often differentiated
only by a toothed hinge.

This is a petri dish I use them to collect samples of similar fossils/rocks.  Any hard clear plastic case could work, like bottles or jars.  But avoid using glass.  As it will break. 

I liked this one the most.

Can you figure out if I am holding a bivalve or a brachiopod?


In the above picture is a Bivalve stuck in stone.  This thumbnail sized snack thrived in the marines of the ancient world (similar to species that thrive today in modern oceans and seas).  This one avoided being eaten only to be fossilized.

So why are fossils like this important to the world of science?
Well there are plenty of reasons, one you can produce a number of various chemicals out of their remains.  Calcium, Hydrogen, Carbons. You can date the strata (the layer of rock) you are digging in.
You can tell what the climate and environment was like in the region at the comparative date.

Why would any of that be important?
Well knowing what layer of rock your digging in will increase chances of knowing what can be discovered.  If I was looking for Dinosaurs this location would be the right peroid of geological time, BUT, Its aquatic, marine.   So its not likely to find land dwelling dinosaurs in a watery grave. 

Yet this does not mean I am not close. Often from sampling many areas that are marine you will often find shale or conglomerates.  These can indicate in which direction I would need to move to find solid dry land.  In this case, If I wanted a dino from this period of time, the evidence points that the land mass I want is in Utah.

Industrially however, there are other key implications the strata of this region can give away.  One is there is shale in the region.  Shale is a common component of paint, plastic, roofing materials, clays and bricks.  So manufactures of those supplies will be interested in the region.

Shale also helps make natural aquifers.  Aquifers are underground sources of water.  Often used in agriculture and housing developments.

One final note to touch on is, ancient marine regions are a great source of oils and natural gas. 

So to sum it up.  Knowing the strata of a region, by the fossil record and rock type can tell scientist what can be found in the region.  Shales to build from, oils and gas to power machines, water to drink, chemicals to use in modern industry, and the reason I like geo science, and probably the best reason, is I get to play in the dirt all day looking at fossils.

What little boy doesn't grow up wanting to do that.