Collection 3: "Big Rocks' Balancing Acts" by Douglas Fox

The 80 mile-per-hour headwind pummeled his face.

James is a geologist, someone who studies the history and movement of the Earth as recorded in rocks, at the University of Nevada in Reno.

Was the boulder there when the first pioneers rolled their wagons by 200 years ago?

He now walks on the sandy bottom of a winding gully with Dylan Rood, a geologist from Lawrence Livermore National Laboratory in California.

If the house is continuously exposed to running water, the cement will gradually wear away.

They can tell, in fact, that it’s sitting within a few centimeters of where it was eroded out of the surrounding bedrock.

They can tell, in fact, that it’s sitting within a few centimeters of where it was eroded out of the surrounding bedrock.

Rood points out a vein of brownish quartz crystals, several fingers thick, that runs through the bedrock a few meters behind the rock.

It would be a pretty unlikely coincidence if the boulder just rolled down the
mountain and landed that way.

This rare form, called beryllium-10, is created when cosmic rays from space hit the rock and split apart larger atoms of oxygen and nitrogen.

And during the winter, ice doesn’t form inside cracks in the rock and slowly
pry it apart.

Here in California, Rood and Richard need to know not only how long their precariously balanced rocks have been standing but also how hard they are to knock over.