Combining constraints from tsunami modeling and sedimentology to untangle the 1969 Ozernoi and 1971 Kamchatskii tsunamis
Combining constraints from tsunami modeling and sedimentology to untangle the 1969 Ozernoi and 1971 Kamchatskii tsunamis
复制标题
结合海啸模型和沉积学的限制来解开 1969 年奥泽尔诺伊海啸和 1971 年堪察加半岛海啸的谜团
DOI：
10.1029/2007gl032349
复制
发表时间：
2008
影响因子：
5.2
通讯作者：
V. Titov
中科院分区：
文献类型：
--
作者：
M. Martin;R. Weiss;J. Bourgeois;T. Pinegina;H. Houston;V. Titov
1969年(7.7兆瓦)和1971年(7.8兆瓦)沿白令海和堪察加最北太平洋海岸发生了大海啸。两次由此引发的海啸都被记录在潮汐测量仪上，但只有1969年的海啸才对冲刺进行了编目观测，这些观测是有限的，也是值得怀疑的。我们使用了海啸沉积的现场测绘和海啸模拟相结合的方法来补充这一历史记录。我们绘制了公元1956年和1964年沿200多公里海岸线的火山灰层上方的海啸沉积物图。然而，1969年和1971年的海啸沉积在现场是无法区分的。海啸堆积高程分布有两个纬度峰值。在58°~57°范围内，沉积物抬升一般在2~4m之间，向南递减。在57°~56°范围内，泥沙抬升一般在3~6m之间(最大超过10m)，向南增加。1969年和1971年海啸的局部抬升模型解释了大部分沉积物分布，区分了某些地区的两次海啸，并阐明了地震的震源机制和破裂区域。
Large tsunamigenic earthquakes occurred in 1969 (Mw 7.7) and 1971 (Mw 7.8) along the Bering Sea and northernmost Pacific coast of Kamchatka. Both resultant tsunamis were recorded on tide gauges, but only the 1969 tsunami has cataloged observations of runup, and these observations are limited and questionable. We used a combination of field mapping of tsunami deposits and tsunami modeling to augment this historical record. We mapped tsunami deposits above A.D. 1956 and 1964 volcanic ash layers, along more than 200 km of shoreline. However, the 1969 and 1971 tsunami deposits are not distinguishable in the field. The distribution of tsunami‐deposit elevation has two latitudinal peaks. From 58° to 57° sediment runup typically ranges from 2 to 4 m, decreasing to the south. From 57° to 56° sediment runup typically ranges from 3 to 6 m (maximum more than 10 m), increasing to the south. Models of local runup for the 1969 and 1971 tsunamis explain most of the sediment distribution, differentiate the two tsunamis in some localities, and elucidate the earthquakes' focal mechanisms and rupture areas.