{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T18:09:51Z","timestamp":1790014191176,"version":"4.0.1"},"reference-count":66,"publisher":"Public Library of Science (PLoS)","issue":"9","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004359","name":"Vetenskapsr\u00e5det","doi-asserted-by":"publisher","award":["2020-03817"],"award-info":[{"award-number":["2020-03817"]}],"id":[{"id":"10.13039\/501100004359","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Rock art serves as a remarkable window into Bronze Age societies and is usually interpreted through motif and setting. The exceptionally well-preserved art in Bohusl\u00e4n is recognized as world heritage with a wide range of imagery engraved into the local Bohus granite. Here we connect the depth of these carvings with near surface structure of this granite by combining ultrasonic pulse-echo B-scans with Structure-from-Motion photogrammetry and DEM based depth modelling for five major panels. The B-scans reveal surface parallel reflective horizons at ~8\u20139 mm and ~18\u201320 mm depth (11 and 25 mm at one site) consistent with para-glacial stress-relief microfracture zones. Our investigation shows an average depth for most figures of ~0.96\u20131.52 mm, and even the deepest carvings lay entirely within the first weak layer. While they exceed the post-glacial depth of weathering (\u22641 mm), which was previously thought to be the limiting factor for carving depth. A nearby, polished but uncarved outcrop lacks reflective layers. We conclude that carvers preferentially selected panels with paraglacial weakening and even show preferential placement on an individual panel. Thus, placement and choice of locations were based on geological necessity and its understanding by the carvers.<\/jats:p>","DOI":"10.1371\/journal.pone.0358075","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T17:23:35Z","timestamp":1790011415000},"page":"e0358075","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Rock carving depth reflects carvers\u2019 geological insight"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-3779-2156","authenticated-orcid":true,"given":"Carina","family":"Liebl","sequence":"first","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Earth Science"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark","family":"Peternell","sequence":"additional","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Earth Science"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Horn","sequence":"additional","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Historical Studies"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Johan","family":"Ling","sequence":"additional","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Historical Studies"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1524-9514","authenticated-orcid":true,"given":"Julian","family":"Moyano Di Carlo","sequence":"additional","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Historical Studies"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashely","family":"Green","sequence":"additional","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Historical Studies"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rich","family":"Potter","sequence":"additional","affiliation":[{"name":"University of Gothenburg","place":["G\u00f6teborg, Sweden"],"department":["Department of Historical Studies"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"issue":"297","key":"pone.0358075.ref001","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1017\/S0003598X00092620","article-title":"A measure of conviction: recording emphasis in Scandinavian rock carvings","volume":"77","author":"J Coles","year":"2003","journal-title":"Antiquity"},{"key":"pone.0358075.ref002","volume-title":"Bilder vid vatten","author":"L Bengtsson","year":"2004","edition":"1"},{"key":"pone.0358075.ref003","doi-asserted-by":"crossref","DOI":"10.2307\/j.ctvh1dpxr","volume-title":"Elevated rock art: towards a maritime understanding of Bronze Age rock art in northern Bohusl\u00e4n","author":"J Ling","year":"2014","edition":"1"},{"key":"pone.0358075.ref004","doi-asserted-by":"crossref","DOI":"10.2307\/j.ctvh1dsjs","volume-title":"Prehistoric rock art in Scandinavia: agency and environmental change","author":"C Nimura","year":"2015","edition":"1"},{"key":"pone.0358075.ref005","volume-title":"Shadows of a northern past: rock carvings in Bohusl\u00e4n and \u00d8stfold","author":"J Coles","year":"2005","edition":"1"},{"key":"pone.0358075.ref006","article-title":"The location of rock pictures is an interpretive element.","volume-title":"Samfunn, symboler og identitet. 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