The Formation Made of Solid Pyrite

[mikeymig]

Leicester Pyrite Member.

 

This layer between the Windom and the Geneseo black shale represents a sea of death. I find very few types of fossils in this hard to process layer of solid pyrite. Well preserved cephalopods and Placoderm armor (Placodermi is a class of armored prehistoric fish) are the most common fossils found. This very thin horizon can be easily found in the outcrop if you just look for rust dripping down and staining the grey shales below this pyrite layer. Every year or two, a piece of Leicester Pyrite will fall from its position high up in the outcrop and slide down to the creeks edge. It takes a lot of work to process the pyrite for fossils. Every blow with your hammer delivers the strong smell of sulfur and a ton of sparks. The reward for all this patience and hard work are fossils preserved in brilliant fools gold. This unit is also the only rocks in my area that routinely contain the armor of Placoderm fish. Click this link for a detailed description of this unusual formation -  http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.835.6976&rep=rep1&type=pdf&fbclid=IwAR0qdFymJq-Hd1_SqU3j3yDw5Trl0ih_KohTv-26Du3b1m9g9s2IYKlW0Xc

[Spoons]

Very Interesting!

[dinosaur man]

On 3/2/2020 at 10:01 PM, Spoons said:

Very Interesting!

Agreed very interesting!! 

On 3/2/2020 at 9:59 PM, mikeymig said:

Leicester Pyrite Member.

 

This layer between the Windom and the Geneseo black shale represents a sea of death. I find very few types of fossils in this hard to process layer of solid pyrite. Well preserved cephalopods and Placoderm armor (Placodermi is a class of armored prehistoric fish) are the most common fossils found. This very thin horizon can be easily found in the outcrop if you just look for rust dripping down and staining the grey shales below this pyrite layer. Every year or two, a piece of Leicester Pyrite will fall from its position high up in the outcrop and slid down to the creeks edge. It takes a lot of work to process the pyrite for fossils. Every blow with your hammer delivers the strong smell of sulfur and a ton of sparks. The reward for all this patience and hard work are fossils preserved in brilliant fools gold. This unit is also the only rocks in my area that routinely contain the armor of Placoderm fish. Click this link for a detailed description of this unusual formation -  http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.835.6976&rep=rep1&type=pdf&fbclid=IwAR0qdFymJq-Hd1_SqU3j3yDw5Trl0ih_KohTv-26Du3b1m9g9s2IYKlW0Xc

I would love to see some of the Placoderm armour!!

[Ludwigia]

I think there's also a similar, if not stratigraphically parallel horizon at Hungry Hollow.

[Shamalama]

3 hours ago, Ludwigia said:

I think there's also a similar, if not stratigraphically parallel horizon at Hungry Hollow.

I think you are referring to the phenomenon in the Hungry Hollow Mbr. of the Widder where pyrite is common in fossils. This does not form a specific "layer" like what Mikey is talking about. Also stratigraphically the Widder is still well down in the Hamilton group and Mikey is up at the top near the boundary of the Givetian period and Fransian period.  The image below is from 

 

Lithofacies and Geochemistry of the Lucas Formation in the subsurface of southwestern Ontario: A High-Purity limestone and potential High-Purity Dolostone resource
September 2004
DOI: 10.13140/RG.2.1.3871.3843
Report number: Open File Report 6137  Affiliation: Ontario Geological Survey

 

 

[Ludwigia]

48 minutes ago, Shamalama said:

I think you are referring to the phenomenon in the Hungry Hollow Mbr. of the Widder where pyrite is common in fossils. This does not form a specific "layer" like what Mikey is talking about. Also stratigraphically the Widder is still well down in the Hamilton group and Mikey is up at the top near the boundary of the Givetian period and Fransian period.  The image below is from 

 

Lithofacies and Geochemistry of the Lucas Formation in the subsurface of southwestern Ontario: A High-Purity limestone and potential High-Purity Dolostone resource
September 2004
DOI: 10.13140/RG.2.1.3871.3843
Report number: Open File Report 6137  Affiliation: Ontario Geological Survey

 

 

 

Thanks for clearing that up for me, Dave.