A sandstone is found to overlie a shale. The shale contains a volcanic ash layer that has been radiometrically dated to 84 million years ago. Both the shale and the sandstone are cut by a pluton of gabbro that has been dated to 60 million years old

How old is the sandstone layer?
A) between 84 and 60 million years old
B) older than 84 millions years old
C) younger than 60 million years old
D) more information is needed to constrain the age


Answer: A

Environmental & Atmospheric Sciences

You might also like to view...

As far back as 1620, Sir Francis Bacon commented on the similarity of the shorelines of western ____________________ and eastern ____________________

Fill in the blank(s) with correct word

Environmental & Atmospheric Sciences

Many shoreline shapes represent a dynamic balance between sediment delivered to the shore by streams and erosion from wave action. Explain how a beach or spit might change over time because of variations in these two processes

What will be an ideal response?

Environmental & Atmospheric Sciences

For which of the following pairs are the atoms most likely to form an ionic bond with each other?

A) carbon and oxygen B) calcium and chlorine C) chlorine and oxygen D) sodium and magnesium

Environmental & Atmospheric Sciences

What geological processes are associated with the upward and downward circulation in the mantle?

What will be an ideal response?

Environmental & Atmospheric Sciences