Eras
the Precambrian era.
what are the different types of fossils?
Cast, Mold, Petrified, preserved, carbonized, trace.
What is the law of superposition?
the law of superposition says that rocks that are lower in the earth's crust are older, while rocks that are higher are younger.
what is relative dating?
relative dating is when you compare fossils by the layer that they're found in.
what is the geologic time scale?
the geologic time scale is a record of major events and diversity of life forms present in earth's history
Why doesn't Pangaea exist today?
Because the tectonic plates moved. to what they are now.
What are index fossils?
Fossils that you use to determine the age of the fossils around it.
What is an intrusion?
an intrusion is when a rock later formed when magma hardens beneath earth's surface.
How is relative dating different from absolute dating?
relative is an estimate, and absolute gives an exact age.
How is sedimentary rock different from igneous?
Sedimentary rock is different from igneous because it was formed by the buildup of mineral deposits, while igneous is formed by the cooling of lava.
What main species of animal lived in the paleozoic era
fish and amphibians.
Why don’t fossils form in igneous rocks?
Because they are formed by the cooling of lava, and any organisms would burn under the heat before fossilizing.
How does a fault impact rock layers?
It shifts them, usually diagonally, and offsets the layers.
What is radioactive decay used for?
To date fossils via radiometric dating.
What information can we get from ice cores?
Climate and atmospheric information over time.
What animal mainly lived in the Mesozoic era
Reptiles and dinosaurs.
name two of the most common thing for a fossil to be preserved in.
rock, ice, tar, amber.
what do intrusions tell about the relative age of the rocks around it?
the rocks around it are older than the intrusion
How is the law of superposition used?
it is used to determine the age of rocks relative to the rocks around it/above and below it.
How are earthquakes used as evidence for the Plate Tectonic Theory?
Because the earthquakes are the movement of plates sifting and hitting each other.
What plants mainly lived in the Paleozoic era?
mosses, ferns, and cones.
Explain how marine fossils could be found on top of mountains.
The sea level in that time could have been higher than the sea level now, leaving marine fossils high up.
How can we use the law of superposition despite faults an nonconformity. (s)
the fault is always younger than the rocks it cuts through.
How does isometric dating work.
By measuring the age of the isotopes on the fossils.
based off the pattern that the time scale eras follow, what major event will cause this era to end?
the extinction of humans.