圣海伦斯山国家火山纪念区的边界小径，美国华盛顿州 Boundary Trail in Mount St. Helens National Volcanic Monument, Washington (© Don Geyer/Alamy)

圣海伦斯山国家火山纪念区的边界小径，美国华盛顿州 Boundary Trail in Mount St. Helens National Volcanic Monument, Washington (© Don Geyer/Alamy)

40年的休养生息 40 years of recovery

Mount St. Helens National Volcanic Monument, Washington

Today is an important day in American history. We're standing on the Boundary Trail at Johnston Ridge in the Mount St. Helens National Volcanic Monument. Forty years ago today, 110,000 acres within Gifford Pinchot National Forest was set aside to memorialize the deadliest and most destructive volcanic eruption in the United States. For nearly nine hours on May 18th, 1980, the Mount St. Helens erupted, forever changing the Washington landscape. The volcanic event started at roughly 8:30 on a Sunday morning with a 5.1 magnitude earthquake. This triggered what is known as a 'lateral eruption,' which means the lava blast comes out of the side of the volcano, rather than the top. The initial blast shaved more than a thousand feet off the mountain's elevation, resulting in a massive avalanche and the destruction of about 150 square miles of the surrounding forest. When the event ended, 57 people had died, 200 homes and almost 200 miles of nearby highway had been destroyed.

The monument was established by President Ronald Reagan in 1982 to preserve the area for research, recreation, and education. The land inside has been left to mostly recover naturally since the eruption. While it's believed that Mount St. Helens will erupt again sometime within the next few centuries, that has not deterred people from hiking and climbing at the monument, which has been allowed since 1986.

圣海伦山国家火山纪念碑，华盛顿

今天是美国历史上重要的一天。我们站在圣海伦斯山国家火山纪念碑的约翰斯顿山脊的边界小道上。四十年前的今天，吉福-平肖国家森林内的110000英亩土地被用来纪念美国最致命、破坏性最大的火山爆发。1980年5月18日，圣海伦斯山爆发了近9个小时，永远改变了华盛顿的景观。火山爆发于周日早上8点30分左右，发生了5.1级地震。这引发了所谓的“侧向喷发”，这意味着熔岩喷发从火山的侧面而不是顶部。最初的爆炸使山的海拔下降了一千多英尺，导致了一场大规模的雪崩，并摧毁了周围约150平方英里的森林。活动结束时，57人死亡，200所房屋和近200英里的附近公路被毁。

该纪念碑由罗纳德·里根总统于1982年建立，旨在保护该地区的研究、娱乐和教育。火山爆发后，火山内部的土地基本上自然恢复。虽然人们相信圣海伦斯山将在未来几个世纪的某个时候再次喷发，但这并没有阻止人们前往这座自1986年以来就被允许的纪念碑进行徒步旅行和攀登。