The Landform Diagram Quiz

Uniformitarianism

A drawn cross-section of a landform that shows the layers that form it

Uniformitarianism, the law of original horizontally, the law of superposition, crosscutting relations, and unconformities

The idea that the present is the key to the past, and that natural laws have remained the same throughout the history of the earth

By showing the order of geologic events that created it and how it has changed over time

In a sequence of undisturbed sedimentary rocks, the oldest rocks are at the bottom and the youngest rocks are at the top

The law of original horizontality states that sedimentary rocks are originally formed in horizontal layers.

The law of superposition states that in any undisturbed sequence of layers of rock, the oldest or first-deposited layer would be on the bottom and the youngest would be on the top.

The principle of crosscutting relations states that any rock or fault that cuts across other rocks is younger than those it cuts across.

Unconformities are surfaces of erosion that separate younger rocks from older ones.

Unconformities can occur because of wind, water, or friction when other rocks scrape along them, like when a glacier slides over the landform.

According to the law of original horizontality and the law of superposition, the layers of rock were laid down first, followed by the folding and bending of the layers.

The main idea of geology is uniformitarianism, which states that the present is the key to the past, or that we can deduce what happened in the past by observing how things work today.

The four key ideas are the law of original horizontality, the law of superposition, crosscutting relations, and unconformities.

The law of original horizontality states that rock layers are originally deposited horizontally.

The law of superposition states that in an undisturbed sequence of rock layers, the youngest rocks are on top and the oldest rocks are on the bottom.

Crosscutting relations refer to the principle that a rock or geologic feature that cuts across another rock or feature is younger than the rock or feature it cuts across.

An unconformity is a surface of erosion or non-deposition that represents a gap in the geologic record.

The two reasons are that the tube of magma does not continue past the unconformity and that layers 6 and 7 are on top of the formation.

The four key ideas help geologists determine events that have occurred long ago and develop some ideas about the order of events that helped shape our landscape.