近日，瑞典斯德哥尔摩大学Jan Magne Cederstrm团队提出了将瑞典时间尺度锚定在放射性碳时间尺度上——De Geer零变的绝对年龄。这一研究成果发表在2025年4月28日出版的《地质学》杂志上。

瑞典时间尺度（STS）基于年度沉积物序列（varves），是详细描述斯堪的纳维亚冰川消融和气候历史的独特工具。经过一个多世纪的发展，STS包括13300个不同的年份，但它与日历年的联系是不安全的，还不能被视为一个真正的绝对时间尺度。因此，不可能可靠地调查STS中记录的与西北欧和北大西洋地区其他气候档案相关的古气候和环境变化的领先和滞后。

研究组对一系列全新世早期冰坝湖排水事件进行了放射性碳定年，这些事件在下游沉积了可识别的洼地。特别是，他们确定了沉积STS所谓“零变”的湖泊排水系统，并将其定为公元1950年（cal.yr B.P.）前10008±87校准年。利用水文模型，研究组证明了排水持续时间是次季节性的，排水标志层按时间顺序是真实的年变化。通过这样做，他们将STS锚定在绝对时间上，提供了最后一次冰川-间冰期过渡的关键冰川和气候事件的修订年龄，并对斯堪的纳维亚中部全新世早期冰盖退缩进行了严格的时间限制重建。

附：英文原文

Title: Anchoring the Swedish Time Scale to the radiocarbon time scale —An absolute age for De Geer’s zero varve

Author: Carl Regnéll, Sarah L. Greenwood, Richard Gyllencreutz, Gustaf Peterson, Joachim Regnéll, Christian hrling, Johannes Hardeng, Ernst Johnson, Jostein Bakke, Jan Magne Cederstrm

Issue&Volume: 2025-04-28

Abstract: The Swedish Time Scale (STS), based on annual sediment sequences (varves), is a unique tool for detailing Scandinavian deglaciation and climate history. Over a century in development, the STS comprises ～13,300 varve-years, yet its connections to calendar years are insecure, and it cannot yet be considered a true absolute time scale. Consequently, it has not been possible to reliably investigate leads and lags of paleoclimate and environmental changes recorded in the STS in relation to other climate archives in NW Europe and the North Atlantic region. Here, we radiocarbon dated a series of early Holocene ice-dammed lake drainage events that deposited recognizable varves downstream. In particular, we identified the lake drainage responsible for depositing the so-called “zero varve” of the STS and dated it to 10,008 ± 87 calibrated years before present, A.D. 1950 (cal. yr B.P.). Using a hydrological model, we demonstrate that drainage duration was subseasonal and that drainage marker beds are, in chronological terms, true annual varves. By doing so, we anchor the STS in absolute time, provide revised ages of key deglacial and climatic events of the last glacial-interglacial transition, and present a tightly chronologically constrained reconstruction of early Holocene ice-sheet retreat in central Scandinavia.

DOI: 10.1130/G53280.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G53280.1/654001/Anchoring-the-Swedish-Time-Scale-to-the