死亡谷国家公园里的优比喜比火山口，加利福尼亚州 Ubehebe Crater in Death Valley National Park, California (© Albert Knapp/Alamy)

死亡谷国家公园里的优比喜比火山口，加利福尼亚州 Ubehebe Crater in Death Valley National Park, California (© Albert Knapp/Alamy)

When Death Valley blew its top

Deep below Death Valley's charred surface, blazing hot magma once gushed up through a geologic fault until it hit groundwater. The magma quickly turned the water to steam, and like a defective subterranean pressure cooker, the Earth's crust blew its top in a ferocious explosion. The hydrovolcanic eruption sent up a mushroom cloud of steam and spewed burnt volcanic cinders for miles. It also left the giant crater seen in this photo and 12 smaller ones spread across the surface.

The Ubehebe Crater (pronounced you-bee-HEE-bee) is a half-mile across and more than 700 feet deep. Geologically speaking, Ubehebe and the other craters here are quite young. A 2016 study concluded that the craters were all formed in a relatively brief series of explosions—a period of days or weeks—about 2,100 years ago. Another eruption could happen, but visitors need not worry about the ground below their feet—seismometers in the region will alert geologists in advance of any future volcanic unrest. A trail around the rim of the crater offers views of the colorful layers of stone along the walls. Adventurous hikers can descend to the bottom, but it's a long slog back out again, especially on a sweltering summer day.

当死亡谷爆发时

在死亡谷烧焦的地表深处，炽热的岩浆曾经通过地质断层喷涌而出，直到触及地下水。岩浆很快将水变成蒸汽，就像一个有缺陷的地下压力锅，地壳在猛烈的爆炸中炸开了顶部。水火山喷发喷出蘑菇状的蒸汽云，喷出燃烧的火山灰数英里。它还留下了这张照片中看到的巨大陨石坑，12个较小的陨石坑散布在地表。

Ubehebe火山口（发音为you bee HEE bee）宽半英里，深700多英尺。从地质学的角度来说，乌贝赫比和这里的其他陨石坑都很年轻。2016年的一项研究得出结论，这些陨石坑都是在相对短暂的一系列爆炸中形成的——大约2100年前的几天或几周时间。另一次火山喷发可能会发生，但游客不必担心脚下的地面。该地区的地震仪将在未来的火山动荡之前提醒地质学家。沿着火山口边缘的小径可以看到沿着墙壁的彩色石层。喜欢冒险的徒步旅行者可以爬到水底，但要想再次爬出来还需要很长时间，尤其是在炎热的夏天。