This photograph shows light-colored granite and darker diorite (both igneous rocks).Which of the following statements is true?
A)The light-colored unit is younger because granite is more continental than diorite.
B)The diorite is older because its weathered surfaces are darker.
C)The granite is younger because it crosscuts the diorite.
D)All of these are correct.

Question

This photograph shows light-colored granite and darker diorite (both igneous rocks).Which of the following statements is true? 
A)The light-colored unit is younger because granite is more continental than diorite. 
B)The diorite is older because its weathered surfaces are darker. 
C)The granite is younger because it crosscuts the diorite. 
D)All of these are correct.

Quizplus · Accepted Answer

The granite crosscuts the diorite, indicating that it is younger. The color of the rocks has no direct relation to their relative age. Continental crust is not necessarily younger than oceanic crust, so the fact that granite is more continental does not determine its age compared to diorite.

This Photograph Shows Light-Colored Granite and Darker Diorite (Both Igneous