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16 Cards in this Set
- Front
- Back
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Late Proterozoic |
650 milion years ago First time Large Animals skeltonized appear |
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Late Cambrian |
Flooding by shallow waters |
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Middle Ordovician |
Ice Age, |
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Middle Silurien |
Large plants and coral reefs expand |
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LAte Cretaceous |
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Pre- Cambrian Early forms of life |
1. Preserved microorganisms 2. stromatolites 3. geochemicals signals carbonaceous matter kerogin stable forms of carbon, nitrogen |
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Preserved Microorganisms |
cyanobacteria |
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stromatolites |
domed shape structure first discovered in Sharks Bay it is a very shallow hypersaline lagoon layers formed by microbial mats, disturbance buries them with sediment on top then colonized by another microbial mats |
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fractionation |
carbon isotopes biological processes co2 fixing step carbon based organisms tend to take up certain carbon isotopes 12:13 ratio |
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Proterozoic |
diversity of microfossil increases lots of different stromatolites no definitive animals yet but cyanobacteria eukaryotes are present in late proterozoic |
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Phanerozic |
Animals appear indefinitely (Metazoan) Ediacaran biota appears |
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Cambrian Explosion 540 MYA |
Rapid increase in skeletonized animal diversity Predator and Prey system Stomatolites decline Rise of PLANTS |
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Cambrian Fauna |
trilobites , inarticulate brachiopods, hyoliths |
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paleozoic fauna |
articulate brachiopods, crinoids, corals, cephalopods, bryozoans |
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modern fauna |
bivalves, gastropods, mairne vertebrates, bryozoans, crsutaceans, echinoids |
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bioturbating |
animals that live in the sediment, also churn up the sediment |
