Question

which feature causes a gap in the geologic record?
○ extrusion
○ fault
○ intrusion
○ erosion

Explanation:

To determine which feature causes a gap in the geologic record (an unconformity), we analyze each option:

• Extrusion: Involves lava cooling at the surface, adding rock layers, not creating a gap.
• Fault: A fracture in rock layers with movement, but doesn't remove layers to create a gap.
• Intrusion: Magma cooling underground, adding rock, not creating a gap.
• Erosion: Removes existing rock layers, which can create a gap (unconformity) in the geologic record as those eroded layers are no longer present to be part of the record.

Answer:

D. erosion