Slow slip and tremor (SST) downdip of the seismogenic zones may trigger megathrust earthquakes by frequently transferring stress to seismogenic zones. Geodetic observations have suggested that the recurrence intervals of slow slip decrease toward the next megathrust earthquake. However, temporal variations in the recurrence intervals of SST during megathrust earthquake cycles remain poorly understood because of the limited duration of geodetic and seismological monitoring of slow earthquakes. The quartz-filled, crack-seal shear veins in the subduction mélange deformed near the downdip limit of the seismogenic zone in warm-slab environments record cyclic changes in the inclusion band spacing in the range from 4 ± 1 to 65 ± 18 μm. The two-phase primary fluid inclusions in quartz between inclusion bands exhibit varying vapor/liquid ratios regardless of inclusion band spacing, suggesting a common occurrence of fast quartz sealing due to a rapid decrease in quartz solubility associated with a large fluid pressure reduction. A kinetic model of quartz precipitation, considering a large fluid pressure change and inclusion band spacing, indicates that the sealing time during a single crack-seal event cyclically decreased and increased in the range from 0.16 ± 0.04 to 2.7 ± 0.8 years, with one cycle lasting at least 27 ± 2 to 93 ± 5 years. The ranges of sealing time and duration of a cycle may be comparable to the recurrence intervals of SST and megathrust earthquakes, respectively. We suggest that the spatial change in inclusion band spacing is a potential geological indicator of temporal changes in SST recurrence intervals, particularly when large fluid pressure reduction occurs by brittle fracturing.

发震区的缓慢滑动和震颤 (SST) 下倾可能会通过频繁地将应力转移到发震区而引发特大地震。大地观测表明慢滑移的重复间隔在下一次超强地震发生时会减少。然而，由于对慢地震的大地测量和地震学监测的持续时间有限，人们对巨型逆冲地震周期中海温重复间隔的时间变化仍然知之甚少。在温暖的板岩环境中，俯冲混杂岩中石英填充的裂缝密封剪切脉在发震带的下倾极限附近变形，记录了包裹带间距在 4 ± 1 至 65 ± 18 μm 范围内的周期性变化。无论包裹体带间距如何，石英中两相原生流体包裹体在包裹体带之间都表现出不同的气/液比，这表明由于与流体压力大幅降低相关的石英溶解度快速下降，石英快速封闭的现象很常见。石英沉淀动力学模型，考虑流体压力变化和包裹体带间距大，表明单次裂缝-封闭事件的封闭时间在0.16±0.04到2.7±0.8年的范围内周期性地减少和增加，一个周期至少持续 27 ± 2 至 93 ± 5 年。封闭时间的范围和周期的持续时间可能分别与海温和特大地震的复发间隔相媲美。