近日，天津大学邵延秀团队报道了利用土壤液化的光激发发光测年进行古地震调查：2021年玛多7.4级地震的启示。相关论文发表在2026年2月10日出版的《中国科学：地球科学》杂志上。

土壤液化是同震震动引发的常见现象，因此对古地震诱发液化的分析可揭示古地震活动的时间与频率。然而，这一方法在限定古地震事件方面的潜力仍未得到充分挖掘。其中一个关键问题在于精确测定古液化事件的发生时间，并将同期液化特征与古地震事件相关联。

研究组展示了应用光释光测年技术来限定2021年玛多地震及江错断裂带先前古地震产生的同震液化特征年龄的可行性。假设沙沸沉积物顶部的光释光信号在喷出地表时完全重置，则表明古液化事件曾破裂至古地表。此外，被液化物质覆盖的古地表的OSL年龄可为古地震的真实发生时间提供估算值。

在二浪哇遗址，研究组识别出三次独立的液化事件。OSL测年直接限定了最新的2021年玛多地震及两次古地震的发生时间，分别约为5 ka和12–13 ka。该研究结果凸显了利用古液化特征OSL测年来揭示特定地质环境（如埋藏于冲积层和浅湖相沉积物中的隐伏断层）中古地震记录的巨大潜力，在这些环境中，液化证据可能是主要的、甚至是唯一的记录。

附：英文原文

Title: Paleoseismic investigation using optically stimulated luminescence dating of soil liquefication: Insights from the 2021 Maduo Mw7.4 earthquake

Author: Guiming HU, Jing LIU-ZENG, Yanxiu SHAO, Chengguo YAN, Longfei HAN, Wenqian YAO, Yunpeng GAO, Wenxin WANG, Yueren XU, Shilong WANG

Issue&Volume: 2026/02/10

Abstract: Soil liquefaction is a common feature triggered by coseismic shaking. Thus, analysis of ancient earthquake-induced liquefaction can uncover the timing and frequency of paleoseismicity. However, its potential remains an under-explored component in constraining paleoseismic events. One key issue is to accurately date the timing of paleoliquefied events and to correlate coeval liquefaction features with paleoseismic events. This study demonstrates the application of optically stimulated luminescence (OSL) dating to constrain the ages of coseismic liquefaction features generated by the 2021 Maduo earthquake and previous paleoearthquakes along the Jiangcuo fault. Assuming that the OSL signals in the sand blow sediments are fully reset at the top indicates that the paleoliquefaction events ruptured the paleosurface. Furthermore, the OSL age of the paleosurface, which is covered by the liquefied materials, provides an estimate for the real age of the paleoearthquake. At the Erlongwa site, we identified three distinct liquefied events. OSL dating directly constrains the most recent 2021 Maduo earthquake and two paleoearthquakes, which occurred at around 5ka, and around 12–13ka, respectively. Our results highlight the great potential of OSL dating of paleoliquefaction features to elucidate paleoseismic records in settings, i.e., blind faults buried within alluvium and shallow lacustrine sediments, where liquefaction evidence may be primary, or even exclusive.

DOI: 10.1007/s11430-025-1779-x

Source: https://www.sciengine.com/SCES/doi/10.1007/s11430-025-1779-x