{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T06:06:10Z","timestamp":1777442770974,"version":"3.51.4"},"reference-count":38,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2020,1,2]],"date-time":"2020-01-02T00:00:00Z","timestamp":1577923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Portuguese Polar Program (PROPOLAR)","award":["PROPOLAR 2017-2018"],"award-info":[{"award-number":["PROPOLAR 2017-2018"]}]},{"name":"CERENA pluriannual funding","award":["UID\/ECI\/04028\/2019"],"award-info":[{"award-number":["UID\/ECI\/04028\/2019"]}]},{"name":"ISR pluriannual funding","award":["UID\/EEA\/50009\/2019"],"award-info":[{"award-number":["UID\/EEA\/50009\/2019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Sorted stone circles are natural surface patterns formed in periglacial environments. Their relation to permafrost conditions make them very helpful for better understanding the past climates where they were formed and have evolved and also for monitoring current underlying processes in case circles are active. These metric scale patterns that occur in clusters of tens to thousands of circular elements, can be more comprehensively characterized if automated methods are used. This paper addresses their identification and delineation through the development and testing of a set of automated approaches, namely, template matching, sliding band filter, and dynamic programming. All of these methods take advantage of the 3D shape of the structures conveyed by digital elevation models (DEM), built from ultra-high resolution imagery captured by unmanned aerial vehicles (UAV) surveys developed in Barton Peninsula, King George Island, Antarctica (62\u00b0S). The best detection results achieve scores above 85%, while the delineations are performed with errors as low as 7%.<\/jats:p>","DOI":"10.3390\/rs12010160","type":"journal-article","created":{"date-parts":[[2020,1,3]],"date-time":"2020-01-03T04:43:03Z","timestamp":1578026583000},"page":"160","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Detection and Delineation of Sorted Stone Circles in Antarctica"],"prefix":"10.3390","volume":"12","author":[{"given":"Francisco","family":"Pereira","sequence":"first","affiliation":[{"name":"ISR, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1000-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3800-7756","authenticated-orcid":false,"given":"Jorge S.","family":"Marques","sequence":"additional","affiliation":[{"name":"ISR, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1000-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1633-0218","authenticated-orcid":false,"given":"Sandra","family":"Heleno","sequence":"additional","affiliation":[{"name":"CERENA, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1000-001 Lisbon, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3199-7961","authenticated-orcid":false,"given":"Pedro","family":"Pina","sequence":"additional","affiliation":[{"name":"CERENA, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1000-001 Lisbon, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,1,2]]},"reference":[{"key":"ref_1","unstructured":"Washburn, A.L. (1980). Geocryology: A Survey of Periglacial Processes and Environments, Wiley."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/0033-5894(86)90085-2","article-title":"Dynamics of periglacial circles in Western Spitsbergen","volume":"26","author":"Hallet","year":"1986","journal-title":"Quat. Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1016\/j.icarus.2008.11.010","article-title":"Sorted stone circles in Elysium Planitia, Mars: Implications for recent martian climate","volume":"200","author":"Balme","year":"2009","journal-title":"Icarus"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"458","DOI":"10.1016\/j.icarus.2010.09.010","article-title":"Sorted clastic stripes, lobes and associated gullies in high-latitude craters on Mars: Landforms indicative of very recent, polycyclic ground-ice thaw and liquid flows","volume":"211","author":"Gallagher","year":"2011","journal-title":"Icarus"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"20120357","DOI":"10.1098\/rsta.2012.0357","article-title":"Stone circles: Form and soil kinematics","volume":"371","author":"Hallet","year":"2013","journal-title":"Philos. Trans. R. Soc. A"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1041","DOI":"10.5194\/tc-8-1041-2014","article-title":"Surface kinematics of periglacial sorted circles using structure-from-motion technology","volume":"8","author":"Kaab","year":"2014","journal-title":"Cryosphere"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"25678","DOI":"10.3402\/polar.v34.25678","article-title":"High-resolution electrical resistivity tomography applied to patterned ground, Wedel Jarlsberg Land, south-west Spitsbergen","volume":"34","author":"Kasprzak","year":"2015","journal-title":"Polar Res."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1111\/1745-5871.12110","article-title":"Contemporary sorted patterned ground in low altitude areas of Tasmania","volume":"53","author":"Slee","year":"2015","journal-title":"Geogr. Res."},{"key":"ref_9","first-page":"179","article-title":"Sorted stone nets and circles of the Columbia Plateau: A hypothesis","volume":"16","author":"Cox","year":"1987","journal-title":"Northwest Sci."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"181","DOI":"10.3402\/polar.v9i2.6790","article-title":"The role of weathering and pedological processes for the development of sorted circles on Kvadehuksletta, Svalbard\u2014A short report","volume":"9","author":"Sollid","year":"1991","journal-title":"Polar Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1017\/S0954102006000307","article-title":"Radiocarbon ages of sorted circles on King George Island, South Shetland Islands, West Antarctica","volume":"18","author":"Jeong","year":"2006","journal-title":"Antarct. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1002\/ppp.1789","article-title":"Morphology, sorting and microclimates of relict sorted polygons, Krkono\u0161e Mountains, Czech Republic","volume":"24","author":"Uxa","year":"2013","journal-title":"Permafr. Periglac. Process."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"663","DOI":"10.1002\/ppp.1949","article-title":"Effect of climate on morphology and development of sorted circles and polygons","volume":"28","author":"Uxa","year":"2017","journal-title":"Permafr. Periglac. Process."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"13287","DOI":"10.1029\/2001JB000279","article-title":"A model for sorted circles as self-organized patterns","volume":"106","author":"Kessler","year":"2001","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"380","DOI":"10.1126\/science.1077309","article-title":"Self-organization of sorted patterned ground","volume":"299","author":"Kessler","year":"2003","journal-title":"Science"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"337","DOI":"10.1002\/esp.430","article-title":"Sorted circles in the Maritime Sub-Antarctic, Marion Island","volume":"28","author":"Holness","year":"2003","journal-title":"Earth Surf. Process. Landforms"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/j.geomorph.2004.01.004","article-title":"Formation of patterned ground and fine-scale soil development within two late Holocene glacial chronosequences: Jotunheimen, Norway","volume":"61","author":"Haugland","year":"2004","journal-title":"Geomorphology"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1002\/esp.3653","article-title":"Laboratory frost sorting by needle ice: A pilot experiment on the effects of stone size and extent of surface stone cover","volume":"40","author":"Yamagishi","year":"2015","journal-title":"Earth Surf. Process. Landforms"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1016\/j.scitotenv.2016.08.104","article-title":"Accurate determination of surface reference data in digital photographs in ice-free surfaces of Maritime Antarctica","volume":"573","author":"Pina","year":"2016","journal-title":"Sci. Total Environ."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"892","DOI":"10.3390\/rs10060892","article-title":"Fluctuation of glacial retreat rates in the eastern part of Warszawa Icefield, King George Island, Antarctica, 1979\u20132018","volume":"10","author":"Angiel","year":"2018","journal-title":"Remote. Sens."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1016\/j.geomorph.2017.03.033","article-title":"UAV-based detection and spatial analyses of periglacial landforms on Demay Point (King George Island, South Shetland Islands, Antarctica)","volume":"290","author":"Dabski","year":"2018","journal-title":"Geomorphology"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"135295","DOI":"10.1016\/j.scitotenv.2019.135295","article-title":"Monitoring recent changes of vegetation in Fildes Peninsula (King George Island, Antarctica) through satellite imagery guided by UAV surveys","volume":"704","author":"Miranda","year":"2020","journal-title":"Sci. Total Environ."},{"key":"ref_23","first-page":"168","article-title":"Assessment of Antarctic moss health from multi-sensor UAS imagery with random forest modelling","volume":"68","author":"Turner","year":"2018","journal-title":"Int. J. Appl. Earth Obs. Geoinf."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1007\/s00300-018-2379-1","article-title":"Study of fauna population changes on Penguin Island and Turret Point Oasis (King George Island, Antarctica) using an unmanned aerial vehicle","volume":"42","author":"Zmarz","year":"2019","journal-title":"Polar Biol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1007\/978-3-030-31332-6_25","article-title":"Detection of stone circles in periglacial regions of Antarctica in UAV datasets","volume":"Volume 11867","author":"Morales","year":"2019","journal-title":"Pattern Recognition and Image Analysis"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1016\/0262-8856(90)90059-E","article-title":"Comparative study of Hough Transform methods for circle finding","volume":"8","author":"Yuen","year":"1990","journal-title":"Image Vis. Comput."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"993","DOI":"10.1016\/j.patcog.2014.08.027","article-title":"A survey of Hough Transform","volume":"48","author":"Mukhopadhyay","year":"2015","journal-title":"Pattern Recognit."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1463","DOI":"10.1109\/TMI.2010.2048253","article-title":"Cell nuclei and cytoplasm joint segmentation using the sliding band filter","volume":"29","author":"Quelhas","year":"2010","journal-title":"IEEE Trans. Med Imaging"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1109\/42.481438","article-title":"Wall position and thickness estimation from sequences of echocardiographic images","volume":"15","author":"Dias","year":"1996","journal-title":"IEEE Trans. Med Imaging"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1581","DOI":"10.1109\/LGRS.2015.2413753","article-title":"Crater delineation by dynamic programming","volume":"12","author":"Marques","year":"2015","journal-title":"IEEE Geosci. Remote. Sens. Lett."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.cmpb.2017.10.028","article-title":"Fast segmentation of the left ventricle in cardiac MRI using dynamic programming","volume":"154","author":"Santiago","year":"2018","journal-title":"Comput. Methods Programs Biomed."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1017\/S0032247419000469","article-title":"The deglaciation of Barton Peninsula (King George Island, South Shetland Islands, Antarctica) based on geomorphological evidence and lacustrine records","volume":"55","author":"Oliva","year":"2019","journal-title":"Polar Rec."},{"key":"ref_33","first-page":"62","article-title":"Periglacial processes and landforms in the South Shetland Islands (northern Antarctic Peninsula region)","volume":"155\u2013156","author":"Serrano","year":"2012","journal-title":"Geomorphology"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1177\/0309133315615805","article-title":"Structure from motion photogrammetry in physical geography","volume":"40","author":"Smith","year":"2016","journal-title":"Prog. Phys. Geogr."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Calvi\u00f1o-Cancela, M., and Mart\u00edn-Herrero, J. (2016). Spectral discrimination of vegetation classes in ice-free areas of Antarctica. Remote. Sens., 8.","DOI":"10.3390\/rs8100856"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1109\/34.368194","article-title":"Dynamic Programming for detecting, tracking, and matching deformable contours","volume":"17","author":"Geiger","year":"1995","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1109\/34.57681","article-title":"Using Dynamic Programming for solving variational problems in vision","volume":"12","author":"Amini","year":"1990","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"213","DOI":"10.1007\/978-3-642-38628-2_25","article-title":"An algorithm for the delineation of craters in very high resolution images of Mars surface","volume":"Volume 7887","author":"Sanches","year":"2013","journal-title":"Pattern Recognition and Image Analysis"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/1\/160\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T14:03:33Z","timestamp":1760364213000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/1\/160"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,1,2]]},"references-count":38,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2020,1]]}},"alternative-id":["rs12010160"],"URL":"https:\/\/doi.org\/10.3390\/rs12010160","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,1,2]]}}}