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约有0.4%的爆发性火山喷发是发生在大的远震后几天之内。偶尔这些“触发的”喷发会比预期的要大很多。人们已经从岩浆超压发生变化当中提出几个机制来解释这种触发,包括气泡增多、气泡上升引起的压力转移,以及岩浆房的翻转。另外,触发喷发也可能是由于岩浆周围的岩石发生破裂而引起的。所有这些机制都需要能够增强由地震引起的小静态应力变化,或者能够将(较大的)瞬变、动态应变转化为永久性压力变化的过程。除了应力的粘弹性松弛外,所有这些过程都可以导致触发喷发的延迟,不过要把地震和延迟触发喷发之间的关系进行量化却不是一件容易的事。泥火山和间歇泉同样会对远震产生反应。能够从超过几百米深处释放出泥浆的泥火山可以被震动所导致的液化作用而触发,因此近似于从地表几米范围内产生的小泥火山。主间歇泉通道周围的岩石骨架由于出现新的破裂而导致其渗透性发生变化。因此这一点可以解释为什么会观测到它们喷发的频度会发生变化。
About 0.4% of explosive volcanic eruptions occurred within a few days of a large teleseismic event. Occasionally these “triggered ” eruptions will be much larger than expected. Several mechanisms have been proposed to explain this triggering from changes in magma overpressure, including increased air bubbles, pressure transfer due to bubble rise, and inversion of magma chambers. In addition, triggered eruptions may also be caused by rupture of rocks surrounding the magma. All of these mechanisms require processes that can enhance small static stress changes caused by earthquakes or convert (larger) transient and dynamic strains into permanent pressure changes. All of these processes, except for the viscoelastic relaxation of stress, can cause delays that trigger eruptions, but quantifying the relationship between earthquakes and delayed trigger eruptions is not easy. Mud volcanoes and geysers also respond to teleseismic events. Mud volcanoes that release mud from depths of more than a few hundred meters can be triggered by the liquefaction caused by vibrations, thus approximating the small mud volcano that occurs within a few meters of the Earth’s surface. The permeability of the rock skeleton around the main geyser channel changes due to new rupture. This therefore explains why the frequency of their eruptions has been observed to change.