Geological Principles Quiz

According to the principles of geologic formations, which layer formed after the fault break in the given context?

Which principle states that smaller rocks or fossils within larger formations must be older than the larger formation?

In the given context, what does intrusion mean in terms of geologic formations?

How can we determine the age of a plant fossil found within a rock formation?

Which principle states that intrusions are younger than the rocks they intrude upon?

If intrusion A is younger than layers B, C, and D, what can we say about layer E?

How do cross-cutting relationships help determine the age of rock formations?

Which principle is demonstrated by the formation of igneous rock within sedimentary rock?

How can we determine the age of a chocolate chip cookie compared to the cookie dough?

Which statement best describes the process by which older rocks can become part of another rock formation?

Uniformitarianism

The Earth's processes have been acting in the same way for billions of years, and the way it acts today is the way it acted in the past.
This principle allows us to assume that the Earth's processes have been consistent over time.

Original Horizontality

Rocks are formed in horizontal layers.
Rocks that are not in horizontal bands have been moved or disturbed since they were formed.
Sediment is moved and compacted over time to form rocks.

Law of Superposition

Older rocks are laid down first and are therefore underneath newer rocks.
This principle applies to geologic formations, with the oldest rocks at the bottom and the newest at the top.

Cross-Cutting Relationships

If a rock formation is cut by a fault, the rocks must have been laid down first.
Something cannot be cut if it was not there to begin with.
This principle helps determine the relative age of rock formations.

Relative Dating

Relative dating is a technique used to compare rocks and fossils to other rocks and fossils in the area.
It creates a relative timeline, showing which objects are older or younger than others, but not their absolute age.
Geologists use relative dating to understand the order of events in the Earth's past.
Paleontologists also use relative dating to understand the formation of fossils.

Intrusive Relationships

Magma often intrudes upon other formations, leaving behind igneous rock formations inside of sedimentary rock.
Intrusions are younger than the rocks they intrude upon.
This principle helps determine the relative age of rock formations.

Inclusions

Smaller rocks or fossils within larger formations must be older than the larger formation.
This principle applies to fossils, which must have died prior to the rock being formed.
Older rocks can get broken up and incorporated into newer rock formations, making them inclusions.

Test your knowledge of fundamental geological principles such as Uniformitarianism and Original Horizontality. Learn about how these concepts help us understand the history of the Earth's surface and the formation of rocks.