Silver Paul G, Behn Mark D
Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015, USA.
Science. 2008 Jan 4;319(5859):85-8. doi: 10.1126/science.1148397.
Although it is commonly assumed that subduction has operated continuously on Earth without interruption, subduction zones are routinely terminated by ocean closure and supercontinent assembly. Under certain circumstances, this could lead to a dramatic loss of subduction, globally. Closure of a Pacific-type basin, for example, would eliminate most subduction, unless this loss were compensated for by comparable subduction initiation elsewhere. Given the evidence for Pacific-type closure in Earth's past, the absence of a direct mechanism for termination/initiation compensation, and recent data supporting a minimum in subduction flux in the Mesoproterozoic, we hypothesize that dramatic reductions or temporary cessations of subduction have occurred in Earth's history. Such deviations in the continuity of plate tectonics have important consequences for Earth's thermal and continental evolution.
尽管人们通常认为俯冲作用在地球上持续不断地进行且从未间断，但俯冲带常常会因海洋闭合和超级大陆聚合而终止。在某些情况下，这可能导致全球范围内俯冲作用的急剧减少。例如，一个太平洋型盆地的闭合将消除大部分俯冲作用，除非这种损失能在其他地方通过相当的俯冲作用起始得到补偿。鉴于地球过去存在太平洋型闭合的证据、缺乏终止/起始补偿的直接机制，以及近期数据支持中元古代俯冲通量的最小值，我们推测在地球历史上曾发生过俯冲作用的急剧减少或暂时停止。板块构造连续性的这种偏差对地球的热演化和大陆演化具有重要影响。
