The rupture mechanisms of deep-focus (> 300 km) earthquakes in subducting slabs of oceanic lithosphere are not well understood and different from brittle failure associated with shallow (< 70 km) earthquakes. Here, we argue that dehydration embrittlement, often invoked as a mechanism for intermediate-depth earthquakes, is a plausible alternative model for this deep earthquake. Our argument is based upon the orientation and size of the plane that ruptured during the deep, 2013 Mw 8.3 Sea of Okhotsk earthquake, its rupture velocity and radiation efficiency, as well as diverse evidence of water subducting as deep as the transition zone and below. The rupture process of this earthquake has been inferred from back-projecting dual-band seismograms recorded at hundreds of seismic stations in North America and Europe, as well as by fitting P-wave trains recorded at dozens of globally distributed stations. If our inferences are correct, the entirety of the subducting Pacific lithosphere cannot be completely dry at deep, transition-zone depths, and other deep-focus earthquakes may also be associated with deep dehydration reactions.

中文翻译：

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深度脱水是 2013 年鄂霍次克海 Mw 8.3 深源地震的合理机制

大洋岩石圈俯冲板块中深源（> 300 km）地震的破裂机制尚不清楚，与浅（< 70 km）地震相关的脆性破坏不同。在这里，我们认为通常被称为中深度地震机制的脱水脆化是这种深度地震的一种可能的替代模型。我们的论点基于在 2013 年 Mw 8.3 鄂霍次克海地震中破裂的平面的方向和大小、破裂速度和辐射效率，以及水俯冲至过渡带及以下深度的各种证据。本次地震的破裂过程是从北美和欧洲数百个地震台站记录的反投影双波段地震图推断出来的，以及通过拟合在全球分布的数十个站点记录的 P 波列车。如果我们的推论是正确的，整个俯冲太平洋岩石圈在深部、过渡带深度不可能完全干燥，其他深源地震也可能与深部脱水反应有关。