The fossilization process, index fossils, and how the fossil record provides evidence for Earth history and evolution.
36 cards · basic cards · AI-written, checked twice. Edit anything.
- What is a fossil?
Show answer
The preserved remains or traces of an organism from the geologic past, typically more than 10,000 years old.- What is a body fossil?
Show answer
A fossil consisting of the actual hard parts of an organism, such as bones, shells, or teeth.- What is a trace fossil?
Show answer
A fossil that records the activity or behavior of an organism, such as footprints, burrows, or trackways.- What is an index fossil?
Show answer
A fossil of an organism that was abundant, widespread, and short-lived, useful for dating and correlating rock layers.- How does a mold fossil form?
Show answer
An organism dissolves away, leaving an empty cavity or depression in the surrounding rock that matches the organism's shape.- How does a cast fossil form?
Show answer
Sediment or mineral matter fills a mold cavity, creating a solid replica of the original organism's external shape.- What is permineralization?
Show answer
A fossilization process where mineral-rich water fills the pores and spaces within an organism's hard parts without replacing the original material.- What is replacement in fossilization?
Show answer
The process where original minerals in an organism's hard parts are slowly dissolved and replaced by different minerals, preserving the organism's form.- What is recrystallization in fossilization?
Show answer
A process where the original mineral structure of an organism's hard parts reorganizes into larger crystals without changing the overall composition.- What is carbonization?
Show answer
A fossilization process where an organism is compressed and leaves only a thin film of carbon residue on the rock surface.- What is a compression fossil?
Show answer
A fossil formed when an organism is flattened under pressure, leaving a thin film of the original material with a relief impression in the rock.- How are organisms preserved in amber?
Show answer
Organisms such as insects become trapped in sticky tree resin, which hardens into amber and excludes oxygen, preventing decomposition.- What are the ideal conditions for fossilization?
Show answer
Rapid burial, anoxic (oxygen-poor) environment, minimal disturbance, and conditions favoring mineral accumulation.- Why is rapid burial important for fossilization?
Show answer
It prevents decomposition by scavengers and bacteria, and allows sediment to quickly cover and protect the organism.- Why do anoxic environments promote fossilization?
Show answer
Without oxygen, decomposing bacteria cannot fully break down organic material, allowing better preservation.
FlashKeepers