To determine the Absolute age of rocks scientist use
Most fossils form when organism die and are buried in
Index Fossils are useful because they can tell what type of age of the rock
Plants and animals first reached land during this Era
When a mineral REPLACES all or parts of an organism it is called a
This radioactive material is used to date rocks that lived up to about 50,000 years ago
A great number of different organisms evolved during this event
Magma that forces its way into rocks and hardens is called an
This era is often called the Age of the Reptile
Pangaea formed at the END of what era?
The process by which all the different kinds of living things have changed over long periods of time is called
Fossils are almost always found in what kind of rock?
This law states that in horizontal layers of sedimentary rock the oldest rock is on the bottom
The earliest form of life appeared during
Radioactive dating is used for this type of rock
An animal with a backbone is called a
On the geologice time scale, eras are divided into
Reptiles evolved from
The time for half of the radioactive atoms to decay in a radioactive element
Humans first appeared at the END of what Era?
The law of superposition is use to determine what type of age for rocks
This event occurred at the end of the Cretaceous period
A scientist who studies fossils is called an
Animals without backbones are called
Dinosaurs ruled the Earth during what Era?
What is Radioactive Dating?
What is sediment?
What is Relative age?
What is the Paleozoic Era?
What is a Petrified Fossil?
What is Carbon-14?
What is the Cambrian Explosion?
What is an Intrusion?
What is the Mesozoic Era?
What is the Paleozoic Era?
What is Evolution?
What is Sedimentary Rock?
What is the Law of Superposition?
What is the Precambrian time?
What are Igneous rocks?
What are vertebrates?
What are periods?
What are Amphibians?
What is the Half-Life?
What is the Cenozoic Era?
What is Relative age?
What is a mass extinction?
What is a Paleontologist?
What are Invertebrates?
What is the Mesozoic Era?
