Relative Dating
Fossils 1
Fossils 2
Features of Relative Dating
Geologic Time
100
any method of determining whether am event or object is older or younger than other events or objects.
Relative Dating
100
The trace or remains of an organism that lived a long time ago, most commonly preserved in Sedimentary rock.
Fossil
100
_____ is a type of fossil that forms when sediments fill in the cavity left by a decomposed organism.
Cast
100
Which formed first: rock layers or faults?
rock layers
100
The graphic organizer that contains divisions of Earth's history is known as
The Geologic Time Scale
200
A principle that states that younger rocks lie about older rocks if the layers have not been disturbed.
Superposition
200
Most often, fossils are formed in this type of rock.
What is sedimentary rock?
200
__________ is a mark or cavity made in a sedimentary surface by a shell or other body.
Mold
200
A gap in the sequence of sedimentary rock layers caused by erosion..
unconformity
200
How is the geologic time scale divided into eras and periods?
According to changes in the fossil record/types or organisms alive/extinctions
300
What is a fault?
A crack in rock layers as a result of movements in Earth's crust.
300
_________ is a process in which the pore space in an organisms hard tissue for example bone or wood is filled with mineral.
Permineralization
300
______ fossil is formed in soft sediments by the movements of animals.
Trace
300
Based on the model, what must have occurred between layers A and B? 
What is erosion?
300
True or False? Explain your answer. Humans were dominant for most of geologic time.
False. If you tried to squeeze Earth's 4.6-billion year history into a 24-hour day, modern humans don't even appear until less than a second before midnight!
400
__________ occurs when internal forces in the Earth slant rock layers.
Tilting
400
What is the relative age of a rock?
age of a rock compared with the age of other rocks in terms of younger or older, but not giving a date or time period
400
______ fossil is found in the rock layers of only one geologic age and that is used to establish the age of the rock layers.
Index
400
This is when magma hardens in rock layers.
What is an intrusion
400
How old is Earth?
4.6 billion years
500
__________ occurs when rock layers bend and buckle from Earth's internal forces.
Folding
500
What kinds of information we get from fossils?
Paleontologists use fossils to help them determine what past life forms were like, how they changed over time, how the Earth's surface has changed and what the past environments were like.
500
The record given by all fossils that have been discovered on Earth.
The Fossil Record
500
How are the three types of unconformities different from one another?
Nonconformities occur between older igneous or metamorphic rock and a younger sedimentary rock layer deposited above it
Disconformities are when the ages of consecutive rock layers don't match up
Angular unconformities are when tilted or folded rock layers are in direct contact with untilted or folded rock layers
500
It states that geologic processes that happened in the past can be explained by current geologic processes.
What is the principle of uniformitarianism?