Term | Definition |
Cenozoic | The cenozoic era has two period and it is the Quaternary and the Tertiary and the years is to 38-to present day.and there is some more stuff and there is Epoch is holocence, ect. |
Mesozoic | The mesozoic era has three period and it is Cretaceous,Jurassic,and triassic and it started 208-65yrs and they didnt have no Epoch in thid time. |
Paleozoic | The paleozoic era it had six period and it is Prrmian,caronierous,Devonian,Silurian,Ordavician,Cambrian and it started 505-245yrs.Then it is does not have Epoch in this period and there is a diffrent events in this period. |
Proterazioc | I dont know the period or the Epoch. in this year it started in 544-2500 and the event is multicelled organisms. |
Molds & Casts | Acids eat away the skeleton or shell and leaves an impression (Molds)in the rock.If the molds fills with manerals, it becomes a cast. |
Tracks & Trails | Imprints are left in mud, which later hardens. Dinosaur tracks are fairly common. |
Carbonization | Oils leaes the plant,and the remaing matter becomes a layer of carbon;in other cases, nitrogen,hydrogen ,and oxgen are distllied from the plants. |
Petrifaction | Minerals in the plant cells crystallize;minerals enter opening or cavities in shells or bones. Common with plants. |
Replacement | Object bured in mud has its molecues replaced by minerals. It is Rare in places. |
Recrystallization | mineral aragonites in shells truns into calcite. Preserves the general shapes of the animals. |
Soft Tissue preservation | Mummification,frozen in ice. Fossils are reativel young and do not last long. |
Traps | Whole organismms locked in tar pits,asphalt,amber,ect. |
Archaean | It dont have a period or Epoch in it but it started in the 2500-3800 and the event is single-celled oraganisms. |
Hadean | This is when the earth started and it started at 3800-4500 and the event i dont know what it is. |