Siberian Permafrost Thawing Accelerated at the B?lling/Aller?d and Preboreal Warm Periods During the Last Deglaciation
Siberian Permafrost Thawing Accelerated at the B?lling/Aller?d and Preboreal Warm Periods During the Last Deglaciation
复制标题
末次冰消期的B?lling/Aller?d 和前寒带温暖期西伯利亚永久冻土融化加速
DOI：
10.1029/2019gl084726
复制
发表时间：
2019
影响因子：
5.2
通讯作者：
Kawakami Shin‐ichi
中科院分区：
文献类型：
--
作者：
Katsuta Nagayoshi;Matsumoto Genki I.;Hase Yoshitaka;Tayasu Ichiro;Haraguchi Takashi F.;Tani Eriko;Shichi Koji;Murakami Takuma;Naito Sayuri;Nakagawa Mayuko;Hasegawa Hitoshi;Kawakami Shin‐ichi
本研究调查了一个连续的沉积物芯，从最深的部分，在呼苏湖，蒙古西北部检索。它的周围是一个连续的西伯利亚永久冻土带。不同的地球化学和岩性特征表明，流域土壤在末次冰消期被湿润，与气候改善。特别是，钙质冰川粘土层（约13.7和约11.0 cal. ka BP），具有高硫含量峰值和δ 34 S值的正位移，与融水脉冲1A和1B的时间相关，分别导致Bølling/Allerød和前北方全新世的快速变暖。这一发现使我们能够解释由滑坡引起的泥石流产生的钙质冰川粘土层，这是由于在突然变暖期间，冻土快速融化导致的强烈排水造成的。我们与贝加尔湖记录的相关性表明，这些永久冻土融化加速了塞伦加流域（欧亚大陆内部）的面积。
This study investigated a continuous sediment core, retrieved from the deepest part in Lake Hovsgol, northwestern Mongolia. Its surrounds are occupied by a continuous Siberian permafrost zone. Distinct geochemical and lithological features suggest that the watershed soil was moistened during the last deglaciation, associated with climate amelioration. Especially, the calcareous glacial clay layers (ca 13.7 and ca 11.0 cal. ka BP), with high sulfur content peaks and positive shifts of δ34S values, well correlate with the timing of meltwater pulses 1A and 1B, leading to rapid warming such as Bølling/Allerød and Preboreal Holocene, respectively. This finding allows our interpretation for the calcareous glacial clay layers produced by landslide‐induced debris flow, which resulted from intensive water discharge from rapid thawing of permafrost during the abrupt warming periods. Our correlation with Lake Baikal records suggests that these permafrost thawings have accelerated over the area of the Selenga drainage basin (continental interior Eurasia).