Geological evidence shows Yellowstone has blown its stack every 700,000 years or so. If nature were truly that regular and reliable, we would be due for another eruption soon, said Valley. However, these processes are subject to variability, so we dont really know when the next eruption will happen.
_____5_____It is the volcanic energy that powers the geysers and hot springs, creates the mountains and canyons, and generates the unique ecosystems that support Yellowstones diverse wildlife.
A Three calderas make up more than a third of Yellowstone National Park.
B The first Yellowstone eruption, 2 million years ago, released more than double that amount of ash and debris.
C The volcano is so inconspicuous that few people know it exists.
D Then, an enormous fountain will shoot high into the air.
E While the active geologist processes at Yellowstone do pose some risk to the public, they also make it a unique treasure.
F Yellowstone National Park attracts the interest of geologists the world over.
【2014年的职称英语考试补全短文练习题(十四)】相关文章:
★ 2015职称英语考试常用语法详解第五讲(动词非谓语形式)
最新
2016-03-01
2016-03-01
2016-03-01
2016-03-01
2016-03-01
2016-03-01