Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23266
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23267
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23285
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23281
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23282
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23283
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23284
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23286
Devil's Postpile, a spectacular example of columnar basalt. Once molten and under great pressure underground, the lava that makes up Devil's Postpile cooled evenly and slowly, contracting and fracturing into polygonal-sided columns. The age of the formation is estimated between 100 and 700 thousand years old. Sometime after the basalt columns formed, a glacier passed over the formation, cutting and polishing the tops of the columns. The columns have from three to seven sides, varying because of differences in how quickly portions of the lava cooled.
Location: Devils Postpile National Monument, California
Image ID: 23287
Sheepeater Cliffs, an example of columnar jointing in basalt due to shrinkage during cooling.
Location: Yellowstone National Park, Wyoming
Image ID: 19794