But a switch has not occurred for 780,000 years—considerably longer than the average time between reversals, about 250,000 years.
But a switch has not occurred for 780,000 years—considerably longer than the average time between reversals, about 250,000 years.
不过，在最近的78万年内都未曾发生过倒转──这比之前发生倒转的平均间隔时间25万年要长了许多。