Microstructural analysis of sandstone from Pravčická brána, the largest rock arch in Europe

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F25%3A10500450" target="_blank" >RIV/00216208:11310/25:10500450 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=R5aDJnzOVh" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=R5aDJnzOVh</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.geomorph.2025.109617" target="_blank" >10.1016/j.geomorph.2025.109617</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Microstructural analysis of sandstone from Pravčická brána, the largest rock arch in Europe

Popis výsledku v původním jazyce

This study uses a multi-method approach to perform a comprehensive microstructural analysis and to discuss the resistance to various weathering processes of sandstone from Pravčická brána, the largest sandstone arch in Europe. In addition to conventionally used methods of sample testing such as mercury intrusion porosimetry, we focused on experimental and non-destructive sample testing such as pore network modelling and permeability simulation based on post-processed μCT images or saturation flow experiments using non-Newtonian fluids - ANA method. These methods showed consistent pore size distribution (PSD) peaks at 18 μm (ANA), 22 μm (PNM) and 48 μm (MIP). The sandstone exhibited high total porosity (34-45 %) and effective porosity (30-42 %), with a network predominantly composed of macropores (&gt;50 nm) that are readily accessible to water. Laboratory tests yielded a permeability of 3.1 x 10(-5) m.s(-1), which is close to the simulated value of 2.21 x 10(-5) m.s(-1). Scanning electron microscopy (SEM) analysis identified features such as quartz grain fractures that were attributed to past frost weathering processes. Analysis of the PSD indicated high resistance of the sandstone studied to freeze-thaw and salt weathering. However, when considering other factors, such as mechanical and hydraulic properties and tectonic predisposition in the arch body, the vulnerability of Pravčická brána becomes more evident. The susceptibility of Pravčická brána sandstone to weathering is increased by its low strength (as evident from previous studies), which is further reduced by ongoing weathering, while the presence of the observed macropores increases the likelihood of fracturing under deformation. This study highlights the need to integrate advanced techniques with traditional methods to provide a comprehensive assessment of sandstone durability.

Název v anglickém jazyce

Microstructural analysis of sandstone from Pravčická brána, the largest rock arch in Europe

Popis výsledku anglicky

This study uses a multi-method approach to perform a comprehensive microstructural analysis and to discuss the resistance to various weathering processes of sandstone from Pravčická brána, the largest sandstone arch in Europe. In addition to conventionally used methods of sample testing such as mercury intrusion porosimetry, we focused on experimental and non-destructive sample testing such as pore network modelling and permeability simulation based on post-processed μCT images or saturation flow experiments using non-Newtonian fluids - ANA method. These methods showed consistent pore size distribution (PSD) peaks at 18 μm (ANA), 22 μm (PNM) and 48 μm (MIP). The sandstone exhibited high total porosity (34-45 %) and effective porosity (30-42 %), with a network predominantly composed of macropores (&gt;50 nm) that are readily accessible to water. Laboratory tests yielded a permeability of 3.1 x 10(-5) m.s(-1), which is close to the simulated value of 2.21 x 10(-5) m.s(-1). Scanning electron microscopy (SEM) analysis identified features such as quartz grain fractures that were attributed to past frost weathering processes. Analysis of the PSD indicated high resistance of the sandstone studied to freeze-thaw and salt weathering. However, when considering other factors, such as mechanical and hydraulic properties and tectonic predisposition in the arch body, the vulnerability of Pravčická brána becomes more evident. The susceptibility of Pravčická brána sandstone to weathering is increased by its low strength (as evident from previous studies), which is further reduced by ongoing weathering, while the presence of the observed macropores increases the likelihood of fracturing under deformation. This study highlights the need to integrate advanced techniques with traditional methods to provide a comprehensive assessment of sandstone durability.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GA21-27291S" target="_blank" >GA21-27291S: Mechanika nenewtonovských tekutin v porézním prostředí: charakterizace hydraulických a transportních vlastností ve vztahu k rozložení velikosti pórů.</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Geomorphology

ISSN

0169-555X

e-ISSN

1872-695X

Svazek periodika

473

Číslo periodika v rámci svazku

March

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

15

Strana od-do

109617

Kód UT WoS článku

001410386400001

EID výsledku v databázi Scopus

2-s2.0-85215627180