Types of Fossils Trace Fossils markings left by
Types of Fossils Trace Fossils – markings left by animals (footprints, trail, burrow). Casts – Minerals fill a space left by a decaying organism. Petrified Fossils – Minerals penetrate, replace hard parts of organism, producing a copy.
Types of Fossils Imprints – Thin object that leaves an imprint when sediment hardens. Molds – Organism is buried then decays, leaving a gap. Amber-Preserved / Frozen – An organism is trapped in ice or sap that hardens.
Rock Types Describe Environments • Slow-moving floodplain – Lake or Lagoon • Shale rock is present.
Rock Types Describe Environments üShallow, warm marine environments üLots of Calcium Carbonate (like seashells) Limestone is formed.
Rock Types Describe Environments Sandstone – Can Describe ALL possible Environments. Terrestrial: • Rivers (sandbars, mouth) • Glacial outwash • Deserts • Lakes Marine (Oceanbased): • Beach • Tidal flats • River/ocean deltas
Minerals Also Describe Environments • Large amounts of Calcium & Magnesium present create Dolomite Rocks • Typical in salty lagoons.
Things Rocks Can Tell Us: 1. What lived in that environment. 2. What the environment looked like. 3. How the environment has changed over time. 4. What things are more recent/ancient.
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