{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T16:03:44Z","timestamp":1779379424372,"version":"3.53.1"},"reference-count":55,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T00:00:00Z","timestamp":1692921600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["41988101-0106"],"award-info":[{"award-number":["41988101-0106"]}]},{"name":"National Natural Science Foundation of China","award":["2019QZKK0708"],"award-info":[{"award-number":["2019QZKK0708"]}]},{"name":"Pioneer Hundred Talents Program of the Chinese Academy of Sciences","award":["41988101-0106"],"award-info":[{"award-number":["41988101-0106"]}]},{"name":"Pioneer Hundred Talents Program of the Chinese Academy of Sciences","award":["2019QZKK0708"],"award-info":[{"award-number":["2019QZKK0708"]}]},{"name":"Second Tibetan Plateau Scientific Expedition and Research Program","award":["41988101-0106"],"award-info":[{"award-number":["41988101-0106"]}]},{"name":"Second Tibetan Plateau Scientific Expedition and Research Program","award":["2019QZKK0708"],"award-info":[{"award-number":["2019QZKK0708"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Tectonic extrusion bypassing the eastern Himalayan syntaxis results in a significant increase in regional stress instability and the associated frequent occurrence of earthquakes in southern Yunnan, China. However, the stress field, and the relationship between the focal mechanism of earthquakes and stress evolution in southern Yunnan, remain enigmatic. In this paper, using a modified grid point test method, we calculated the focal mechanism of ML \u2265 2.5 earthquakes in southern Yunnan (22\u201325\u00b0 N, 100\u2013104\u00b0 E) from January 2009 to June 2023. Utilizing the solutions of historical earthquake focal mechanisms, we obtained the present-day regional tectonic stress field in southern Yunnan via inversion. The results indicate complex and diverse seismic focal mechanisms, and the main types of earthquakes are strike-slip events, followed by normal fault and reverse fault events. The orientations of the maximum and minimum principal stress axes rotate in a clockwise direction from northeast to southwest. The internal stress orientation distribution of the rhombic Sichuan\u2013Yunnan block in the study area is consistent, and the block boundary zone is the site where stress deflection occurs, and the regional tectonic stress field is influenced by the interaction among different blocks. The distribution of R-value in the Lamping\u2013Simao block gradually increases from north to south, indicating that the compressive stress required for material transport becomes relatively small. Combined with the geological and tectonic background of the study area, our results suggest that the speed of block movement gradually decreases from north to south; the distribution of R-value in the South China block is significantly smaller than that of the interior of the Sichuan\u2013Yunnan rhombus, and the proportion of compressive stresses is larger, indicating a stronger extrusion in this region, which may be related to the fact that the Sichuan\u2013Yunnan rhombus is strongly resisted by the South China block in the east.<\/jats:p>","DOI":"10.3390\/s23177406","type":"journal-article","created":{"date-parts":[[2023,8,25]],"date-time":"2023-08-25T08:42:20Z","timestamp":1692952940000},"page":"7406","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Present-Day Tectonic Stress Evolution in Southern Yunnan Based on Focal Mechanisms"],"prefix":"10.3390","volume":"23","author":[{"given":"Wenjie","family":"Fan","sequence":"first","affiliation":[{"name":"State Key Laboratory of the Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"Yunnan Earthquake Agency, Kunming 650244, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8369-0294","authenticated-orcid":false,"given":"Ye","family":"Zhu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of the Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"University of the Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4506-8183","authenticated-orcid":false,"given":"Yingfeng","family":"Ji","sequence":"additional","affiliation":[{"name":"State Key Laboratory of the Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"University of the Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lili","family":"Feng","sequence":"additional","affiliation":[{"name":"Qinghai Earthquake Agency, Xining 810001, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8019-2633","authenticated-orcid":false,"given":"Weiling","family":"Zhu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of the Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"University of the Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7010-4097","authenticated-orcid":false,"given":"Rui","family":"Qu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of the Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"University of the Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,25]]},"reference":[{"key":"ref_1","first-page":"3144","article-title":"A grid search method for determination of tectonic stress tensor using qualitative and quantitative data of active faults and its application to the Urumqi area","volume":"58","author":"Wan","year":"2015","journal-title":"Chin. 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