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Petrified Remains: process by which organic matter is replaced by minerals turning it into stone.
Mold: the hollow shape in a rock left behind after an organism decays (think of the empty space in a baking pan).
Cast: sediments fill in the mold or space left behind in a rock by an organism, showing the same shape as the organism (3-D)
Mold and Cast
The fossil on the left is the MOLD and the fossil on the right is the CAST.
Carbonaceous Film: heat/pressure force gases and liquids from an organism, leaving a thin film of carbon behind.
Trace Fossil: mark or evidence of the activities of an organism. Such as teeth marks, foot prints, burrows, and fossilized animal droppings.
Freezing: freezing prevents substances from decaying.
Amber: sticky resin from trees that traps an organism and hardens.
Tar Pits: large pools of tar that trapped animals when they went to drink the water that usually covered the pools.
Fossils require 3 conditions to occur in order for the remains of an organism to become fossilized.
1. Protection from decomposers (microorganisms, scavengers, and fungi)
Explanation: Protection from decomposers will ensure that some of the organism remains to become fossilized.
2. Quick burial under sediments.
Explanation: A quick burial provides protection from decomposers.
3. Presence of hard body or plant parts.
Explanation: Hard parts are more likely to fossilize because they decay slowly. Soft parts, such as skin and organs, decay very quickly and are rarely preserved (except in the case of original remains).
Fossil: preserved remains or evidence of a once-living thing.