近日，新西兰奥克兰大学Joel A. Baker团队报道了无处可藏：火山灰入侵新西兰石灰岩洞穴。相关论文发表在2025年8月19日出版的《地质学》杂志上。

石灰岩洞穴通常位于火山区域附近，可以保存过去火山喷发的信号，为岩溶发育和洞穴演化提供了重要的年代地层限制。

研究组记录了新西兰怀托莫喀斯特地区的五个洞穴，这些洞穴含有来自陶普火山带的火山灰（tephra），陶普火山带是一个高度活跃的硅火山活动区域。岩洞型矿床由于不受风化作用而呈玻璃状，其中一个例子是分选不良，在火山碎屑流充满洞穴的地方局部硬化。其他沉积物是层状的，据推测是水从地表火山灰沉积物中重新注入洞穴。

玻璃成分分析表明，分布于洞穴地面、顶腔及壁面的火山灰源自四次破火山口形成喷发（包括155万年前的恩加罗马喷发、100万年前的基德纳珀斯喷发、34.9万年前的华卡马鲁喷发，以及约5万年前的罗托伊蒂喷发），另有一次源自陶波火山的低强度喷发（约4万年前）。这些发现凸显了爆炸式火山喷发对该地区的持续影响。洞穴中的洞穴研究提供了重要的信息，可以以限制洞穴沉积物和火山历史，脊椎动物化石年代学，洞穴系统和景观演化为主题。

附：英文原文

Title: Nowhere to hide: Volcanic ash invasion of limestone caves in New Zealand

Author: Sneha Suresh, Simon J. Barker, Paul W. Williams, Colin J.N. Wilson, Trevor H. Worthy, Jeffrey Lang, John Hellstrom, Travis Cross, Shane J. Cronin, Joel A. Baker

Issue&Volume: 2025-08-19

Abstract: Limestone caves are commonly located close to volcanic regions and can preserve signals of past eruptions, providing crucial chronostratigraphic constraints within and beyond U-Th dating limits for karst development and cave evolution. Here we document five caves in the Waitomo karst region of New Zealand that contain volcanic ash (tephra) from the Taupō Volcanic Zone, a highly active region of silicic volcanism. The cave-hosted deposits are glassy due to their protection from weathering, with one example being poorly sorted and locally indurated where pyroclastic flows filled the cave. Other deposits are bedded and inferred to have been water remobilized into the caves from surficial ash deposits. Glass compositions indicate that tephras located in cave floors and roof cavities and on cave walls were sourced from four caldera-forming eruptions, the 1.55 Ma Ngaroma, 1 Ma Kidnappers, 349 ka Whakamaru, and ca. 50 ka Rotoiti events, plus a smaller-volume event from Taupō volcano at ca. 40 ka, highlighting the repeated impact of explosive eruptions on this region. Tephra studies in caves thus provide crucial information that can be used to constrain cave sediment and volcanic histories, vertebrate fossil chronologies, and cave system and landscape evolution.

DOI: 10.1130/G53695.1

Source: https://pubs.geoscienceworld.org/gsa/geology/article/doi/10.1130/G53695.1/660663/Nowhere-to-hide-Volcanic-ash-invasion-of-limestone