Seismic observations of transient subglacial water‐flow beneath MacAyeal Ice Stream, West Antarctica
Seismic observations of transient subglacial water‐flow beneath MacAyeal Ice Stream, West Antarctica
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DOI：
10.1029/2009gl037730
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发表时间：
2009-06
影响因子：
5.2
通讯作者：
J. P. Winberry;S. Anandakrishnan;R. Alley
中科院分区：
文献类型：
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作者：
J. P. Winberry;S. Anandakrishnan;R. Alley
报道了西南极MacAyeal冰流下谐波地震的新观测结果。我们在六周内记录的两次震颤事件中的每一次都持续了大约10分钟的3 Hz能量到达。在此期间，震源位置迁移了几公里。地震的谐波性质被解释为冰下充水裂缝和管道共振的结果。持续时间，单色的性质，和运动的震颤表明，源机制可能是流动的冰下水系统从一个小的冰下湖的排放。我们的研究结果表明，冰下水系统产生重复的，小的突发洪水，可能对冰流动力学的影响。
New seismic observations of harmonic tremors beneath MacAyeal Ice Stream, West Antarctica are reported. Each of the two tremor events that we recorded during a six week period had sustained arrival of 3 Hz energy for approximately 10 minutes. During that time the source location migrated a few kilometers. The harmonic nature of the tremors is interpreted as the result of resonance in subglacial water‐filled cracks and conduits. The duration, monochromatic nature, and movement of the tremor indicate that the source mechanism is likely flow in the subglacial water system resulting from the discharge from a small subglacial lake. Our results suggest that the subglacial water system produces repeated, small outburst floods, with possible implications for ice‐stream dynamics.