地球的地质活动在过去的2.5亿年里平静下来了吗?-地江南体育网页版球科学资料交换江南电子竞技平台 最近的30张来自earthscie.stackexchange.com 2023 - 04 - 02 - t17:50:15z //www.hoelymoley.com/feeds/question/20521 https://creativecommons.org/licenses/by-sa/4.0/rdf //www.hoelymoley.com/q/20521 4 地球的地质活动在过去的2.5亿年里平静下来了吗? 彼得-让莫妮卡复职 //www.hoelymoley.com/users/5396 2020 - 11 - 29 - t12:34:14z 2020 - 11 - 30 - t11:29:11z 在过去，由于大规模的火山爆发，地球的生态系统经历了灾难性的大规模灭绝。一个例子是2.52亿年前的“大灭绝”事件。根据a 2 Jean-Marie Prival的回答是:地球的地质活动在过去的2.5亿年里平静下来了吗? 让-玛丽•Prival //www.hoelymoley.com/users/18081 2020 - 11 - 30 - t11:29:11z 2020 - 11 - 30 - t11:29:11z 你提到的大规模火山喷发被称为大火成岩省(lip)，可能与地幔柱有关。他们已经被调查了一段时间了。Ernst &Buchan(2001)建立了一个包含300多个lip的数据库，并用它来分析它们的时间分布等。以下是他们获得的年龄谱:

在这里输入图像描述

…“确定的”和“可能的”羽头事件发生在整个地质记录中，至少从3500 Ma开始，可能从3800 Ma开始，自3500 Ma以来没有超过200 Myr的无羽间隔。羽头到达没有明显的周期性。< / p >

If you look at the cumulative frequency diagram, there seems to be a increase in event frequency over the last 150 Ma:

enter image description here

There are periods when plume activity appears to be more intense than at other times. These intervals are identified by steeper slopes on a cumulative plot of LIP frequency. The most prominent are at 2800–2700, 2200–1800, 150–0 Ma and more speculatively at 1300–1100 Ma.

But as the authors explain, this is a bias due to the fact that the recent record preserves both oceanic and continental LIPs. However, the oceanic crust is consistently recycled (it's nowhere older than ~200 Ma), thus older events are continental LIPs only. If corrected to include only continental LIPs in the recent (< 150 Ma) record, the trend seems "normal" (dotted line).
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