Evolution of natural rock arches: A realistic small-scale experiment

Abstract

Research Article| December 12, 2018 Evolution of natural rock arches: A realistic small-scale experiment Jaroslav Řihošek; Jaroslav Řihošek * 1Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic *E-mail: rihosekjaroslav@gmail.com Search for other works by this author on: GSW Google Scholar Martin Slavík; Martin Slavík 1Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic Search for other works by this author on: GSW Google Scholar Jiří Bruthans; Jiří Bruthans 1Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic Search for other works by this author on: GSW Google Scholar Michal Filippi Michal Filippi 2Institute of Geology of the Czech Academy of Sciences, Rozvojová 269, 165 00 Prague 6, Czech Republic Search for other works by this author on: GSW Google Scholar Author and Article Information Jaroslav Řihošek * 1Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic Martin Slavík 1Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic Jiří Bruthans 1Faculty of Science, Charles University, Albertov 6, 128 43 Prague 2, Czech Republic Michal Filippi 2Institute of Geology of the Czech Academy of Sciences, Rozvojová 269, 165 00 Prague 6, Czech Republic *E-mail: rihosekjaroslav@gmail.com Publisher: Geological Society of America Received: 26 Jul 2018 Revision Received: 23 Oct 2018 Accepted: 12 Nov 2018 First Online: 12 Dec 2018 Online Issn: 1943-2682 Print Issn: 0091-7613 © 2018 Geological Society of America Geology (2019) 47 (1): 71–74. https://doi.org/10.1130/G45421.1 Article history Received: 26 Jul 2018 Revision Received: 23 Oct 2018 Accepted: 12 Nov 2018 First Online: 12 Dec 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Jaroslav Řihošek, Martin Slavík, Jiří Bruthans, Michal Filippi; Evolution of natural rock arches: A realistic small-scale experiment. Geology 2018;; 47 (1): 71–74. doi: https://doi.org/10.1130/G45421.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract People tend to admire well-developed rock arches and bridges as a symbol of perfection in nature. However, the origin of such arches still remains unclear, with different authors emphasizing different factors as essential. An authentic small-scale physical model of a perfect arch was created in situ from friable sandstone through a simulation of natural erosion. Based on three-dimensional photogrammetric and numerical modeling, we established three evolutionary stages of the modeled arch: the initial, mature, and senile stages. Erosion removed the material from stress shadows, thus exposing the compressed zone of the material, which spans over the discontinuity. From its original lintel thickness with a length ratio of 0.3, the modeled arch thinned out to a ratio of 0.03, which is close to the best-developed natural arches. The erosion rate of the arch surface was relatively low for 90% of its lifespan, but the last 10% was characterized by an abrupt increase in the erosion rate. Our results show that the only conditions essential to producing a delicate arch through erosion are a thin, vertically elongated rock body with an appropriate discontinuity, and a material prone to stress-controlled erosion. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.