Question
A geologist finds some tilted sedimentary rock layers.
Which conclusion can the geologist draw by looking at the rock layers?
Their absolute age is 600 million years.
They were tilted before they were deposited.
They were originally deposited horizontally.
The youngest layer was originally deposited as the bottom layer.
Which conclusion can the geologist draw by looking at the rock layers?
Their absolute age is 600 million years.
They were tilted before they were deposited.
They were originally deposited horizontally.
The youngest layer was originally deposited as the bottom layer.
Answers
GPT-4o mini
The geologist can conclude that **they were originally deposited horizontally**.
Sedimentary rock layers typically form in horizontal layers due to the settling of sediments under the influence of gravity. If the layers are found to be tilted, it indicates that they were deposited in a horizontal position first and then subsequently altered by geological forces (such as tectonic activity) that caused the tilting. This means that the original deposition was horizontal, and the tilting occurred after the rocks were formed.
The other conclusions can be dismissed for the following reasons:
- The absolute age of the rocks cannot be determined solely by their tilt or layering.
- They were tilted after deposition, not before.
- The youngest layer was not originally deposited as the bottom layer; the layers are stacked with the oldest on the bottom and the youngest on the top, unless they have been disturbed.
Sedimentary rock layers typically form in horizontal layers due to the settling of sediments under the influence of gravity. If the layers are found to be tilted, it indicates that they were deposited in a horizontal position first and then subsequently altered by geological forces (such as tectonic activity) that caused the tilting. This means that the original deposition was horizontal, and the tilting occurred after the rocks were formed.
The other conclusions can be dismissed for the following reasons:
- The absolute age of the rocks cannot be determined solely by their tilt or layering.
- They were tilted after deposition, not before.
- The youngest layer was not originally deposited as the bottom layer; the layers are stacked with the oldest on the bottom and the youngest on the top, unless they have been disturbed.