Relative Dating and Ordering of Rock Layers

Front

What is the Law of Superposition?

Back

The Law of Superposition states that in undisturbed rock layers, the oldest layers are at the bottom and the youngest layers are at the top.

Front

What does it mean when a rock layer is described as 'intrusive'?

Back

An intrusive rock layer is formed when magma pushes into existing rock layers and solidifies beneath the Earth's surface.

Front

What is an 'extrusion' in geology?

Back

An extrusion is when lava flows out of a volcano and solidifies on the Earth's surface, forming a new rock layer.

Front

How can fossils help determine the age of rock layers?

Back

Fossils can indicate the relative age of rock layers; if a fossil is found in a layer, it suggests that the layer is from the time period when that organism lived.

Front

What is relative dating in geology?

Back

Relative dating is a method used to determine the age of rocks and fossils in relation to one another, without determining their exact age.

Front

What is the significance of the principle of original horizontality?

Back

The principle of original horizontality states that layers of sediment are originally deposited horizontally. If they are found tilted or folded, it indicates geological events occurred after their formation.

Front

What does 'younger' mean in the context of rock layers?

Back

'Younger' refers to rock layers that were formed more recently compared to other layers, typically found above older layers.

Front

What is an example of a geological feature that can disrupt the Law of Superposition?

Back

An intrusion, such as a volcanic plug, can disrupt the Law of Superposition by cutting through existing layers.

Front

What is the difference between relative dating and absolute dating?

Back

Relative dating determines the order of events without exact dates, while absolute dating provides a specific age or date for rock layers or fossils.

Front

What is a fossil?

Back

A fossil is the preserved remains or traces of a once-living organism, often found in sedimentary rock.