Topic
Stratigraphy
4 questions tagged Stratigraphy — spanning every one of the seven Ws.
what
What is an unconformity in geology?
An unconformity is a gap in the rock record, where younger rocks sit on top of older rocks after erosion or non-deposition. It shows that a long span of time is missing from the geologic sequence.
GeologyStratigraphy
whose
Whose observations first explained the origin of fossils in rock layers?
Nicolaus Steno laid the foundations of stratigraphy in the 17th century. He showed that fossils are remains of once-living organisms and that rock layers form in sequence.
Earth ScienceStratigraphy
when
When was the Great Unconformity first recognized by geologists?
It was recognized in the 18th century, notably by James Hutton in the 1780s.
Earth ScienceStratigraphy
how
How do geologists identify an unconformity in the rock record?
They look for a gap in time where layers are missing, eroded, or tilted before newer layers were deposited. Unconformities mark periods when deposition stopped or rocks were removed.
Earth ScienceStratigraphy