Abstract Clastic deposits in Kalacka Cave in the Tatra Mts. Show soft-sediment deformation structures (SSDS) rare for a cave environments. The poorly sorted allochthonous sediments were deposited within a cave sump under a fluvial regime, likely due to glacially initiated back-flooding during the Last Glacial. The structures include small-scale faults (normal and reverse), folds (upright symmetric anticlines, low-amplitude open folds, W-vergent folds and fault-propagation folds), and water-escape structures. A laboratory experiment is used to assess the possibile liquefaction of a thin soft-sediment filling in a limestone tube, including calculation of the site effects of resonance frequency and amplification coefficient and the site vulnerability index Kg. The calculations indicate that seismic waves can be amplified up to 10 times and the expected resonance frequency is ~17.05 Hz. We argue that the observed SSDS formed in two stages. First, brittle and ductile deformation structures developed due to gravity-induced slumping. Next, liquefaction produced water-escape structures. The studied SSDS were likely seismically triggered. Favorable conditions occurred during the withdrawal of the last glacier (MIS 2) when the sediments were oversaturated and the Tatra Mts. experienced a strong earthquake (M7.0). Alternatively, high-frequency microearthquakes could have been triggered by slope failure cutting into Kalacka Cave.

中文翻译：

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洞穴沉积物中的软沉积物变形结构及其可能的原因（Kalacka Cave，Tatra Mts.，波兰）

塔特拉山Kalacka洞穴中的碎屑沉积物摘要。显示洞穴环境中罕见的软沉积物变形结构 (SSDS)。分类不良的外来沉积物沉积在河流制度下的洞穴水坑内，可能是由于末次冰期期间冰川引发的回灌。构造包括小规模断层（正反）、褶皱（直立对称背斜、低幅张开褶皱、W 辐合褶皱和断层传播褶皱）和逃水构造。实验室实验用于评估石灰石管中薄软沉积物填充的可能性，包括计算共振频率和放大系数的场地效应以及场地脆弱性指数 Kg。计算表明，地震波可以放大 10 倍，预期共振频率约为 17.05 Hz。我们认为观察到的 SSDS 分两个阶段形成。首先，由于重力引起的坍塌形成了脆性和韧性变形结构。接下来，液化产生了逃水结构。研究的 SSDS 很可能是地震触发的。当沉积物过饱和和塔特拉山（Tatra Mts）撤出最后一个冰川（MIS 2）时，出现了有利条件。经历了强烈地震（M7.0）。或者，高频微地震可能是由切入 Kalacka 洞穴的斜坡破坏引发的。接下来，液化产生了逃水结构。研究的 SSDS 很可能是地震触发的。当沉积物过饱和和塔特拉山（Tatra Mts）撤出最后一个冰川（MIS 2）时，出现了有利条件。经历了强烈地震（M7.0）。或者，高频微地震可能是由切入 Kalacka 洞穴的斜坡破坏引发的。接下来，液化产生了逃水结构。研究的 SSDS 很可能是地震触发的。当沉积物过饱和和塔特拉山（Tatra Mts）撤出最后一个冰川（MIS 2）时，出现了有利条件。经历了强烈地震（M7.0）。或者，高频微地震可能是由切入 Kalacka 洞穴的斜坡破坏引发的。