The Dolomites of northern Italy feature some of the most intensively studied carbonate rocks worldwide. Yet, little is known about the long karst history of this mountain range dating back to the Miocene. This study scrutinizes three caves (F10, Milchloch and Cioccherloch) in the Fanes-Sennes-Prags Nature Park (Province of South Tyrol) and the adjacent Fosses area in the Natural Park of Ampezzo Dolomites (Province of Belluno, Veneto). Paleo-phreatic passages of these limestone caves mostly follow a NW-SE orientation, similar to the nearby Val Salata fault. A multi-method approach including cave morphological and isotopic analyses of wall-rock cores was applied to reconstruct the multi-stage speleogenetic history of these cavities. Clastic sediments partly cemented to the cave walls and paragenetic features such as ceiling channels and solutional ramps are present in all studied caves. F10 cave shows widespread laughöhle geometries, including inverted cone chambers and horizontal passages with trapezoid cross sections, characteristic of slow water convection in a hypogene regime. Drill cores in F10 cave exhibit a systematic depletion in both oxygen and carbon isotopes close to the cave wall. The thickness of this isotopically altered zone ranges from a few mm to 4 cm and alteration can sometimes also be macroscopically identified. The amplitude of the isotopic shift ranges from 2.0 to 5.0‰ for δ¹³C and from 1.9 to 4.9‰ for δ¹⁸O. One of the wall rock cores from Cioccherloch also shows a thin isotopic halo, while no evidence of isotopic alteration was found in Milchloch. Our results provide strong geochemical evidence of wall rock alteration driven by hypogene water-rock interaction in at least two of the caves. We propose an early hypogene speleogenetic phase, followed by uplift and denudation resulting in the opening of these cavities to the surface that allowed clastic sediment influx. The sediment infill in combination with the abundant paragenetic features records a second phase in the karst evolution. This paragenetic phase did not involve hypogene waters, as indicated by the lack of isotopic alteration in the wall rock of paragenetic features. The latest phase of speleogenesis is represented by vadose morphologies and vadose speleothems locally dating back to at least 650 ka. This study demonstrates that the combination of morphological analyses and geochemical fingerprinting represents a powerful approach to decipher the commonly complex speleogenetic history of limestone caves.

意大利北部的白云岩具有全球范围内研究最深入的碳酸盐岩。然而，人们对这个山脉的中岩层起源于中新世的悠久岩溶历史知之甚少。这项研究仔细检查了Fanes-Sennes-Prags自然公园（南蒂罗尔省）中的三个洞穴（F10，Milchloch和Cioccherloch）以及Ampezzo Dolomites自然公园（贝伦诺省，威尼托省）的相邻Fosses地区。这些石灰岩洞穴的古今通道大多遵循NW-SE方向，类似于附近的Val Salata断层。应用一种包括壁岩心的洞穴形态学和同位素分析在内的多方法方法，来重建这些空洞的多阶段成岩历史。碎屑沉积物部分地胶结在洞穴壁上，所有研究的洞穴中都存在共生特征，例如天花板通道和固溶斜坡。F10洞穴显示出广泛的哈夫勒几何形状，包括倒圆锥形腔室和具有梯形横截面的水平通道，这是在次生状态下缓慢对流的特征。F10洞穴中的钻芯在靠近洞穴壁处的氧气和碳同位素中都表现出系统性的消耗。同位素改变区域的厚度范围从几毫米到4厘米，有时也可以从宏观上识别出这种改变。δ的同位素位移幅度在2.0到5.0‰之间 子流域中慢水对流的特性。F10洞穴中的钻芯在靠近洞穴壁处的氧气和碳同位素中都表现出系统性的消耗。同位素改变区域的厚度范围从几毫米到4厘米，有时也可以从宏观上识别出这种改变。δ的同位素位移幅度在2.0到5.0‰之间 子流域中慢水对流的特性。F10洞穴中的钻芯在靠近洞穴壁处的氧气和碳同位素中都表现出系统性的消耗。同位素改变区域的厚度范围从几毫米到4厘米，有时也可以从宏观上识别出这种改变。δ的同位素位移幅度在2.0到5.0‰之间¹³ C和1.9〜4.9‰，δ ¹⁸O. Cioccherloch的围岩岩心之一也显示出稀薄的同位素晕，而在Milchloch中未发现同位素改变的证据。我们的结果提供了强有力的地球化学证据，表明至少两个洞穴中的次生水-岩石相互作用驱动了围岩蚀变。我们提出了一个早期的次生造山作用阶段，随后发生隆起和剥蚀作用，导致这些空洞向表面开放，使得碎屑沉积物大量涌入。沉积物填充物与丰富的共生特征相结合，记录了岩溶演化的第二阶段。该同生相不涉及次生水，如同生特征的围岩中缺乏同位素变化所表明的那样。脾生成的最新阶段由渗流形态和渗流鞘脂局部代表，至少可以追溯到650 ka。这项研究表明，形态学分析和地球化学指纹图谱的结合代表了一种解读石灰岩洞穴通常复杂的成岩历史的有力方法。