北大西洋中脊发生5.5级地震 震源深度10公里 无伤亡报告
美国地质调查局（USGS）测定，北大西洋中脊11月14日发生5.5级地震，震源深度10公里。地震发生于协调世界时14日16时26分，震中位于北纬30.122度、西经42.635度的海底，USGS 事件编号为 us7000ty84，测定结果已经地震学家复核。
USGS 的 PAGER 灾害评估系统对这次地震给出绿色等级，即预计不会造成显著人员伤亡与经济损失。由于震中远离陆地、位于无人居住的开阔海底，USGS 未收到有感报告，也没有人员伤亡或财产损失的报告，海啸方面没有相关通报。
大西洋中脊是纵贯大西洋南北的海底山脉系统，是美洲板块与欧亚、非洲板块之间缓慢张裂的扩张边界，海底在这里不断生成新的洋壳。这条山脊绝大部分位于深海之下，只在冰岛等地露出海面。
正因为板块在这里持续分离，中脊沿线地震频繁，但大多发生在远离人群的海底。这次地震震级适中，未对航运和沿岸地区构成已知影响。
（来源：美国地质调查局）
Magnitude 5.5 Earthquake Strikes Northern Mid-Atlantic Ridge; No Casualties Reported
A magnitude 5.5 earthquake struck the northern Mid-Atlantic Ridge on Nov. 14, the U.S. Geological Survey said. The quake occurred at 16:26 UTC at a depth of 10.0 km, with its epicenter at 30.122 degrees north, 42.635 degrees west beneath the Atlantic Ocean. The USGS event, catalogued as us7000ty84, has been reviewed by a seismologist.
The USGS PAGER system assigned the event a green alert level, meaning significant casualties and damage are not expected. Because the epicenter lies in a remote, uninhabited stretch of ocean floor, the USGS received no felt reports, and there were no reports of casualties or damage and no tsunami bulletin associated with the event.
The Mid-Atlantic Ridge is the submarine mountain system running the length of the Atlantic Ocean, a divergent boundary where the American plates are slowly pulling away from the Eurasian and African plates and new oceanic crust is formed. Most of the ridge lies deep underwater, surfacing above sea level in places such as Iceland.
Earthquakes are frequent along the ridge as the plates separate, but most occur far from populated areas. The magnitude 5.5 event had no known impact on shipping or coastal regions.
(Source: U.S. Geological Survey)
来源：美国地质调查局
发布：GSM·美国（发布链接）
图片来源：图片来源：Wikimedia Commons，大西洋中脊在冰岛露出海面的段落（Bar Harel 摄，CC BY-SA 4.0）
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