Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Earth-Moon Ages
Name: Brenda
Status: Student
Age: 18
Location: N/A
Country: N/A
Date: N/A 


Question:
If the ages of Earth and Moon are nearly identical...why are most rocks found on the Moon so much older than Earth rocks?



Replies:
The reason is that the moon stopped being geologically active soon after it formed, but the earth is still active. By "active," I mean that the earth is constantly recycling its minerals: rocks that have been formed erode, wash out to sea, and are carried into the earth's mantle with subducting tectonic plates, to melt and perhaps come to the surface again as lava. The age of a rock is the time since the rock solidified.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois



Click here to return to the Environmental and Earth Science Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory