Transcript Mazon Creek Fossils

Mazon Creek Fossils
Siderite time capsules
John Schneider
What are they?
• Fossils from Illinois
• Francis Creek Shale
• Pennsylvanian period
• Siderite nodules
Nodule Formation
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Something Dies
Remains are buried
Bacteria consume the remains
CO2 combines with Fe from the water
Siderite forms around the remains
Nodule Formation
Depositional Environment
• Marine Bay
• Muddy Swamp
• Rivers
Getting at the fossil
• The organism creates a plane of weakness
• The nodule splits in two halves
Splitting Nodules
• Basic technique
Splitting Nodules
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Another Technique, Weathering
– How to weather a siderite nodule
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Submerge in water
Freeze
Thaw
Repeat until broken
Types of Fossils
• 400 species from 130 genera
– Uncertainty due to plant taxonomy
• Plant types
– Shoreline and riverbank growth
– Horsetails
– Trees
– Ferns
Types of Fossils
• Animals
– Over 320 species
– 2 specific faunas, Braidwood and Essex
• Essex fauna
– Shallow marine
• Braidwood fauna
– Freshwater and land animals
Essex Fauna
• Primarily invertibrates
– Jellyfish
– Worms
– Bivalves
– Snails
• Also, multiple fish species
Braidwood fauna
• Freshwater fish
• Various terrestrial arthropods
• Freshwater crustaceans
Discovery
• Late 1800’s
• Joseph Even
• Sent to Berlin
• Swift notoriety
Discovery
• World War I
• Strip mining
• George Langford
• Field Museum Mazon Creek project