{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T16:41:53Z","timestamp":1776444113905,"version":"3.51.2"},"reference-count":28,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2020,11,28]],"date-time":"2020-11-28T00:00:00Z","timestamp":1606521600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003700","name":"Korea Institute of Geoscience and Mineral Resources","doi-asserted-by":"publisher","award":["GP2020-010"],"award-info":[{"award-number":["GP2020-010"]}],"id":[{"id":"10.13039\/501100003700","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In-situ stress estimation plays an important role on the success of an underground project. However, no method is error-free, and therefore a combination of methods is desirable. In this study, the in-situ stresses for a geothermal project have been assessed through the analysis of a deep rock core taken at 4.2 km, using the diametrical core deformation analysis (DCDA) method that relates the diametrical core expansion after stress relief with the stresses assuming elastic deformation. The extracted granodiorite core sample of 100 mm of diameter was intersected with a closed joint at a dip angle of 80.8\u00b0 with respect to the vertical coring direction. The core sample was scanned using an industrial X-ray computed tomography (CT), and the diametrical deformation measurements were computed with CT slices. Results from using the DCDA method indicated an average horizontal stress difference of 13.3 MPa, similar to that reported for a nearby exploration well. Furthermore, the stress orientations were compared with the orientation of maximum roughness values. The results indicated a correlation between the orientation of the maximum horizontal stress and the orientation of the minimum joint roughness coefficient, implying a possible tracking of stress orientation using joint roughness anisotropy.<\/jats:p>","DOI":"10.3390\/s20236802","type":"journal-article","created":{"date-parts":[[2020,11,29]],"date-time":"2020-11-29T21:00:57Z","timestamp":1606683657000},"page":"6802","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Stress Estimation through Deep Rock Core Diametrical Deformation and Joint Roughness Assessment Using X-ray CT Imaging"],"prefix":"10.3390","volume":"20","author":[{"given":"Hanna","family":"Kim","sequence":"first","affiliation":[{"name":"Korea Institute of Geoscience and Mineral Resources, 124, Gwahak-ro Yuseong-gu, Daejeon 34132, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Melvin B.","family":"Diaz","sequence":"additional","affiliation":[{"name":"Department of Energy &amp; Resources Engineering, Korea Maritime and Ocean University, 727, Taejongro, Yeongdo-gu, Busan 49112, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joo Yeon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Energy &amp; Resources Engineering, Korea Maritime and Ocean University, 727, Taejongro, Yeongdo-gu, Busan 49112, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong-Bok","family":"Jung","sequence":"additional","affiliation":[{"name":"Korea Institute of Geoscience and Mineral Resources, 124, Gwahak-ro Yuseong-gu, Daejeon 34132, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kwang Yeom","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Energy &amp; Resources Engineering, Korea Maritime and Ocean University, 727, Taejongro, Yeongdo-gu, Busan 49112, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"63","DOI":"10.2208\/jscej1969.1977.258_63","article-title":"estimation of spatial geo-stress components in rock samples using the kaiser effect of acoustic emission","volume":"1977","author":"Kanagawa","year":"1977","journal-title":"Proc. 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