[Abstract Hyaloclastites develop where lava interacts with water resulting in deposits that have a unique and often complex range of petrophysical properties. A combination of eruptive style and emplacement environment dictates the size, geometry and distribution of different hyaloclastite facies and their associated primary physical properties such as porosity, permeability and velocity. To date, links between the 3D facies variability within these systems and their petrophysical properties remain poorly understood. Hjorleifshofði in southern Iceland presents an exceptional outcrop exposure of an emergent hyaloclastite sequence >1 km wide by >200 m high and enables an investigation of the distribution of the hyaloclastite deposits at seismic scale. Within this study we present a photogrammetry‐based 3D model from part of this recent hyaloclastite delta and incorporate previous work by Watton et al. (Journal of Volcanology and Geothermal Research, 2013, 250, 19) to undertake detailed facies interpretation and quantification. Laboratory petrophysical analyses were performed on 34 core plugs cut from key field facies samples, including P‐ and S‐wave velocity, density, porosity and permeability at both ambient and confining pressure. Integration of the 3D model with the petrophysical data has enabled the production of pseudo‐wireline logs and property distribution maps which demonstrate the variability of physical properties within hyaloclastite sequences at outcrop to seismic scale. Through comparison of our data with examples of older buried hyaloclastite sequences we demonstrate that the wide‐ranging properties of young hyaloclastites become highly uniform in older sequences making their identification by remote geophysical methods for similar facies variations more challenging. Our study provides an improved understanding of the petrophysical property distribution within hyaloclastite sequences and forms a valuable step towards improving the understanding of similar subsurface sequences and their implications for imaging and fluid flow., We present a photogrammetry‐based 3D reconstruction of Hjorleifshofði in southern Iceland which provides an exceptional outcrop exposure of an emergent hyaloclastite sequence. By incorporating detailed facies interpretations and laboratory petrophysical analyses into the model, we have produced pseudo‐wireline logs and property distribution maps to demonstrate the variability of physical properties at seismic scale. Our study provides an improved understanding of the petrophysical property distribution within hyaloclastite sequences and forms a valuable step towards improving the understanding of similar subsurface sequences and their implications for imaging and fluid flow. ]

中文翻译：

---

Hyaloclastite Delta 矿床的 3D 相结构和岩石物理特性：来自冰岛南部的综合摄影测量和岩石物理研究

[摘要透明碎屑岩在熔岩与水相互作用的地方形成，从而形成具有独特且通常复杂的岩石物理特性范围的沉积物。喷发方式和侵位环境的结合决定了不同透明碎屑岩相的大小、几何形状和分布及其相关的主要物理特性，如孔隙度、渗透率和速度。迄今为止，对这些系统内 3D 相变异性与其岩石物理特性之间的联系仍知之甚少。冰岛南部的 Hjorleifshofði 提供了一个特殊的露头暴露的新兴透明碎屑岩序列，宽度大于 1 公里，高度大于 200 米，并且能够在地震尺度上对透明碎屑岩沉积物的分布进行调查。在这项研究中，我们提出了一个基于摄影测量的 3D 模型，该模型来自最近的透明碎屑岩三角洲的一部分，并结合了 Watton 等人以前的工作。(Journal of Volcanology and Geothermal Research, 2013, 250, 19) 进行详细的相解释和量化。对取自关键油田相样品的 34 个岩心塞进行了实验室岩石物理分析，包括在环境压力和围压下的 P 波和 S 波速度、密度、孔隙度和渗透率。将 3D 模型与岩石物理数据相结合，可以生成伪电缆测井和特性分布图，这些图展示了露头到地震尺度的透明碎屑岩序列内物理特性的可变性。通过将我们的数据与较旧的埋藏透明碎屑岩序列的例子进行比较，我们证明年轻透明碎屑岩的广泛特性在较旧的序列中变得高度一致，这使得通过远程地球物理方法对相似相变化的识别更具挑战性。我们的研究提供了对透明碎屑岩序列中岩石物理特性分布的更好理解，并为提高对类似地下序列的理解及其对成像和流体流动的影响的理解迈出了宝贵的一步。我们展示了冰岛南部 Hjorleifshofði 的基于摄影测量的 3D 重建这提供了一个新兴的透明碎屑岩序列的特殊露头暴露。通过将详细的相解释和实验室岩石物理分析纳入模型，我们制作了伪电缆测井和特性分布图，以证明地震尺度上物理特性的可变性。我们的研究提供了对透明碎屑岩序列内岩石物理特性分布的更好理解，并为提高对类似地下序列的理解及其对成像和流体流动的影响的理解迈出了宝贵的一步。]