Q 01/05

Pinnacles National Park is in which U.S. state?

A) Nevada

B) Arizona

C) California

D) Oregon

Answer · why

C) California

It sits about 80 miles southeast of San Jose and 40 miles inland from the Pacific.

Q 02/05

The park's rock spires are the eroded remains of what?

A) An ancient coral reef

B) A meteor impact crater

C) An extinct volcano

D) A glacial moraine

Answer · why

C) An extinct volcano

Only the western half is here; the eastern half sits near Lancaster, roughly 200 miles to the southeast.

Q 03/05

Which famous fault carried the park's rocks some 195 miles northwest from where they erupted?

A) San Andreas

B) Hayward

C) Garlock

D) Calaveras

Answer · why

A) San Andreas

The fault itself has since shifted about four miles east of the park; its old line is visible as the Chalone Creek fault.

Q 04/05

What is the name of the long-dead volcano, near present-day Lancaster, that the park's rocks came from?

A) Neenach

B) Sutter Buttes

C) Coso

D) Mammoth

Answer · why

A) Neenach

Ten rock types match in the same order at both sites, which made the pair a textbook example of plate tectonics.

Q 05/05

Roughly how long ago did that volcano erupt?

A) About 2 million years ago

B) About 23 million years ago

C) About 65 million years ago

D) About 230 million years ago

Answer · why

B) About 23 million years ago

The fault has moved the two halves apart at about 1.5 centimetres a year, roughly six inches a decade.