{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T22:39:25Z","timestamp":1780439965271,"version":"3.54.1"},"reference-count":29,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,26]],"date-time":"2021-04-26T00:00:00Z","timestamp":1619395200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"the National Key Research and Development Program of China","award":["2019YFC1509201"],"award-info":[{"award-number":["2019YFC1509201"]}]},{"name":"the National Natural Science Foundation of China","award":["41904001"],"award-info":[{"award-number":["41904001"]}]},{"name":"he National Postdoctoral Program for Innovative Talents","award":["BX20180220"],"award-info":[{"award-number":["BX20180220"]}]},{"name":"the China Postdoctoral Science Foundation","award":["2018M640733"],"award-info":[{"award-number":["2018M640733"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>With the development of interferometric synthetic aperture radar (InSAR), the seismic deformation observation density increases sharply. Data down-sampling can effectively reduce the observation density and the computational cost for subsequent researches. Considering the saliency of the deformation field, we introduce a saliency-based quadtree algorithm for down-sampling (SQS). Three simulation experiments show that SQS can effectively distinguish the near-field and far-field deformation, as well as reduce the amount of observation, while keeping the detailed information of the main deformation near the fault. SQS can avoid the interference of far-field local deformation better than the traditional quadtree sampling algorithm (QS), thus obtaining better inversion results. We took the Dingri earthquake on 20 March 2020 as a case study to verify the advantages of SQS in dealing with real earthquake deformation. We obtained the co-seismic deformation from the ascending and descending Sentinel-1 for the Dingri earthquake, using QS and SQS for sampling and inversion separately. The results show the advantages of SQS in data volume reduction, observation distribution, anti-interference of local deformation, and inversion accuracy. Our preferred solution based on SQS shows that the Dingri earthquake was caused by a normal fault slip. The main slip area is 2\u20135.5 km deep with a maximum slip of 0.68 m. The estimated geodetic moment is 3.14 \u00d7 1017 Nm, corresponding to a magnitude of Mw5.63.<\/jats:p>","DOI":"10.3390\/rs13091678","type":"journal-article","created":{"date-parts":[[2021,4,27]],"date-time":"2021-04-27T06:19:11Z","timestamp":1619504351000},"page":"1678","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["An Improved Quadtree Sampling Method for InSAR Seismic Deformation Inversion"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7310-050X","authenticated-orcid":false,"given":"Hua","family":"Gao","sequence":"first","affiliation":[{"name":"State Key Laboratory of Information Engineering in Surveying, Mapping, and Remote Sensing, Wuhan University, Wuhan 430079, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mingsheng","family":"Liao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Information Engineering in Surveying, Mapping, and Remote Sensing, Wuhan University, Wuhan 430079, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guangcai","family":"Feng","sequence":"additional","affiliation":[{"name":"School of Geosciences and Info-Physics, Central South University, Changsha 410083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1038\/364138a0","article-title":"The displacement field of the Landers earthquake mapped by radar interferometry","volume":"364","author":"Massonnet","year":"1993","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41467-020-17587-6","article-title":"How satellite InSAR has grown from opportunistic science to routine monitoring over the last decade","volume":"11","author":"Biggs","year":"2020","journal-title":"Nat. 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