Tag archives: geology

Now that it’s spring and we’re starting to travel again, our local deserts have become popular nearby attractions. Joshua Tree, Death Valley, and the Mojave Desert are at their best this time of year and you might even catch some wildflowers if they got enough rain. At NASA, in addition to enjoying seasonal wildflowers, we […]

Most people know that Earth’s climate has changed periodically over the last couple of million years. Ice ages have come and gone along with wetter and drier periods in the more temperate zones. Picture two miles of ice on top of Canada and the northern United States, glaciers snaking down from the Sierra Nevada, lakes […]

On my first geological field trip as a new geology major at Caltech, I was amazed as we drove out into the Mojave Desert on Interstate 15 when my professor, who was driving, would point through the window at a distant rock outcropping and say: “There’s a Miocene (five to 20 million years of age) […]

Almost everybody who’s looked at a map of the Atlantic Ocean has noticed that South America and Africa fit together. Alfred Wegener noticed too and proposed in 1915 that they indeed were together long ago. He was laughed out of the room. The reason was that he couldn’t say how and why they had split […]