{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T20:14:56Z","timestamp":1771272896897,"version":"3.50.1"},"reference-count":58,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,11,5]],"date-time":"2019-11-05T00:00:00Z","timestamp":1572912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The Key Research Program of the Chinese Academy of Sciences","award":["NO. XDPB11-3"],"award-info":[{"award-number":["NO. XDPB11-3"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["No.41571388"],"award-info":[{"award-number":["No.41571388"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Craters contain important information on geological history and have been widely used for dating absolute age and reconstructing impact history. The impact process results in a lot of ejected fragments and these fragments may form secondary craters. Studies on distinguishing primary craters from secondary craters are helpful in improving the accuracy of crater dating. However, previous studies about distinguishing primary craters from secondary craters were either conducted by manual identification or used approaches mainly concerning crater spatial distribution, which are time-consuming or have low accuracy. This paper presents a machine learning approach to distinguish primary craters from secondary craters. First, samples used for training and testing were identified and unified. The whole dataset contained 1032 primary craters and 4041 secondary craters. Then, considering the differences between primary and secondary craters, features mainly related to crater shape, depth, and density were calculated. Finally, a random forest classifier was trained and tested. This approach showed a favorable performance. The accuracy and F1-score for fivefold cross-validation were 0.939 and 0.839, respectively. The proposed machine learning approach enables an automated method of distinguishing primary craters from secondary craters, which results in better performance.<\/jats:p>","DOI":"10.3390\/rs11212594","type":"journal-article","created":{"date-parts":[[2019,11,7]],"date-time":"2019-11-07T02:48:31Z","timestamp":1573094911000},"page":"2594","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["A Machine Learning Approach to Crater Classification from Topographic Data"],"prefix":"10.3390","volume":"11","author":[{"given":"Qiangyi","family":"Liu","sequence":"first","affiliation":[{"name":"State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1580-4979","authenticated-orcid":false,"given":"Weiming","family":"Cheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China"},{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing 210023, China"},{"name":"CAS Center for Excellence in Comparative Planetology, Hefei 230052, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5030-748X","authenticated-orcid":false,"given":"Guangjian","family":"Yan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote Sensing and Digital Earth of Chinese Academy of Sciences, Beijing 100088, China"},{"name":"Beijing Engineering Research Center for Global Land Remote Sensing Products, Institute of Remote Sensing Science and Engineering, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunliang","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Civil Engineering and Architecture, Southwest Petroleum University, Chengdu 610500, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianzhong","family":"Liu","sequence":"additional","affiliation":[{"name":"University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Lunar and Planetary Science Research Center, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1344","DOI":"10.1029\/2017JE005446","article-title":"Lunar Orientale Impact Basin Secondary Craters: Spatial Distribution, Size-Frequency Distribution, and Estimation of Fragment Size","volume":"123","author":"Guo","year":"2018","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1016\/j.icarus.2018.02.031","article-title":"Investigation of the depth and diameter relationship of subkilometer-diameter lunar craters","volume":"309","author":"Sun","year":"2018","journal-title":"Icarus"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1504","DOI":"10.1126\/science.1195050","article-title":"Global Distribution of Large Lunar Craters: Implications for Resurfacing and Impactor Populations","volume":"329","author":"Head","year":"2010","journal-title":"Science"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1134\/S0038094618010021","article-title":"Size-Frequency Distribution of Small Lunar Craters: Widening with Degradation and Crater Lifetime","volume":"52","author":"Ivanov","year":"2018","journal-title":"Sol. Syst. Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1125","DOI":"10.1038\/nature04069","article-title":"Secondary craters on Europa and implications for cratered surfaces","volume":"437","author":"Bierhaus","year":"2005","journal-title":"Nature"},{"key":"ref_6","unstructured":"Melosh, H.J. (1989). Impact Cratering: A Geologic Process, Oxford Universitr Press."},{"key":"ref_7","unstructured":"Bierhaus, E.B., Merline, W.J., and Chapman, C.R. (2005). Variation in Size-Distributions between Adjacent and Distant Secondary Craters. Lunar Planet. Sci. Conf., Abstract#238."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1186\/s40562-018-0116-9","article-title":"On the importance of self-secondaries","volume":"5","author":"Xiao","year":"2018","journal-title":"Geosci. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2277","DOI":"10.1002\/2015JE004860","article-title":"Size-frequency distribution of crater populations in equilibrium on the Moon","volume":"120","author":"Xiao","year":"2015","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1016\/j.icarus.2011.11.033","article-title":"Planetary surface dating from crater size\u2013frequency distribution measurements: Spatial randomness and clustering","volume":"218","author":"Michael","year":"2012","journal-title":"Icarus"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"223","DOI":"10.1016\/j.epsl.2009.12.041","article-title":"Planetary surface dating from crater size\u2013frequency distribution measurements: Partial resurfacing events and statistical age uncertainty","volume":"294","author":"Michael","year":"2010","journal-title":"Earth Planet. Sci. Lett."},{"key":"ref_12","unstructured":"Wilhelms, D.E. (1976, January 15\u201319). Secondary impact craters of lunar basins. Proceedings of the 7th Lunar Science Conference, Houston, TX, USA."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"2380","DOI":"10.1029\/2018JE005652","article-title":"Lunar Cold Spots and Crater Production on the Moon","volume":"123","author":"Williams","year":"2018","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"535","DOI":"10.1146\/annurev.earth.34.031405.125018","article-title":"The importance of secondary cratering to age constraints on planetary surfaces","volume":"34","author":"McEwen","year":"2006","journal-title":"Annu. Rev. Earth Planet. Sci."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"351","DOI":"10.1016\/j.icarus.2005.02.009","article-title":"The rayed crater Zunil and interpretations of small impact craters on Mars","volume":"176","author":"Mcewen","year":"2005","journal-title":"Icarus"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"406","DOI":"10.1016\/j.icarus.2008.10.011","article-title":"Theoretical analysis of secondary cratering on Mars and an image-based study on the Cerberus Plains","volume":"200","author":"Werner","year":"2009","journal-title":"Icarus"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"415","DOI":"10.1007\/BF00562581","article-title":"Laboratory simulation of the herringbone pattern associated with lunar secondary crater chains","volume":"9","author":"Oberbeck","year":"1974","journal-title":"Moon"},{"key":"ref_18","first-page":"907","article-title":"Secondary-Impact Craters on the Moon: Topographic Form and Geologic Process","volume":"9","author":"Pike","year":"1978","journal-title":"Lunar Planet. Sci. Conf."},{"key":"ref_19","first-page":"E12004","article-title":"Constraints on Europa\u2019s surface properties from primary and secondary crater morphology","volume":"115","author":"Bierhaus","year":"2010","journal-title":"J. Geophys. Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"870","DOI":"10.1016\/j.pss.2011.04.004","article-title":"Chandrayaan-1 observation of distant secondary craters of Copernicus exhibiting central mound morphology: Evidence for low velocity clustered impacts on the Moon","volume":"59","author":"Keerthi","year":"2011","journal-title":"Planet. Space Sci."},{"key":"ref_21","first-page":"E06008","article-title":"Detection of small lunar secondary craters in circular polarization ratio radar images","volume":"115","author":"Wells","year":"2010","journal-title":"J. Geophys. Res."},{"key":"ref_22","first-page":"L07203","article-title":"Using lunar boulders to distinguish primary from distant secondary impact craters","volume":"34","author":"Bart","year":"2007","journal-title":"Geophys. Res. Lett."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"31","DOI":"10.1016\/j.pss.2017.06.001","article-title":"Morphometric studies of the Copernicus and Tycho secondary craters on the moon: Dependence of crater degradation rate on crater size","volume":"162","author":"Basilevsky","year":"2018","journal-title":"Planet. Space Sci."},{"key":"ref_24","first-page":"E10007","article-title":"Geomorphic analysis of small rayed craters on Mars: Examining primary versus secondary impacts: Analysis of small rayed craters on mars","volume":"114","author":"Calef","year":"2009","journal-title":"J. Geophys. Res."},{"key":"ref_25","first-page":"E02S08","article-title":"Crater gradation in Gusev crater and Meridiani Planum, Mars","volume":"111","author":"Grant","year":"2006","journal-title":"J. Geophys. Res."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1181","DOI":"10.1016\/S0273-1177(01)00488-4","article-title":"Reconsideration of crater size-frequency distribution on the moon: Effect of projectile population and secondary craters","volume":"28","author":"Nagumo","year":"2001","journal-title":"Adv. Space Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"125","DOI":"10.5194\/isprs-archives-XLII-3-W1-125-2017","article-title":"Automatic detection of secondary craters and mapping of planetary surface age based on lunar orbital images","volume":"XLII-3\/W1","author":"Salih","year":"2017","journal-title":"ISPRS-Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"343","DOI":"10.1016\/j.icarus.2019.06.018","article-title":"Impact cratering in and around the Orientale Basin: Results from recent high-resolution remote sensing datasets","volume":"333","author":"Wu","year":"2019","journal-title":"Icarus"},{"key":"ref_29","unstructured":"Honda, C., Kinoshita, T., Hirata, N., and Morota, T. (2014, January 7\u201312). Detection abilities of secondary craters based on the clustering analysis and Voronoi diagram. Proceedings of the European Planetary Science Congress, Cascais, Portugal."},{"key":"ref_30","first-page":"3325","article-title":"Statistical Characterization of Spatial Distribution of Impact Craters: Implications to Present-Day Cratering Rate on Mars","volume":"1353","author":"Kreslavsky","year":"2007","journal-title":"LPI Contrib."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"5777","DOI":"10.1109\/TGRS.2019.2902198","article-title":"Active Machine Learning Approach for Crater Detection from Planetary Imagery and Digital Elevation Models","volume":"57","author":"Wang","year":"2019","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"3681","DOI":"10.1109\/TGRS.2018.2806371","article-title":"Lunar Crater Detection Based on Terrain Analysis and Mathematical Morphology Methods Using Digital Elevation Models","volume":"56","author":"Chen","year":"2018","journal-title":"IEEE Trans. Geosci. Remote Sens."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.pss.2018.03.003","article-title":"Automatic detection of lunar craters based on DEM data with the terrain analysis method","volume":"160","author":"Zhou","year":"2018","journal-title":"Planet. Space Sci."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.cageo.2016.07.013","article-title":"Contour-based automatic crater recognition using digital elevation models from Chang\u2019E missions","volume":"97","author":"Zuo","year":"2016","journal-title":"Comput. Geosci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"2419","DOI":"10.1016\/j.asr.2014.08.018","article-title":"A machine learning approach to crater detection from topographic data","volume":"54","author":"Di","year":"2014","journal-title":"Adv. Space Res."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"885","DOI":"10.1109\/LGRS.2012.2226432","article-title":"Crater Detection Using the Morphological Characteristics of Chang\u2019E-1 Digital Elevation Models","volume":"10","author":"Xie","year":"2013","journal-title":"IEEE Geosci. Remote Sens. Lett."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/j.icarus.2009.04.026","article-title":"Machine cataloging of impact craters on Mars","volume":"203","author":"Stepinski","year":"2009","journal-title":"Icarus"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1023\/A:1010933404324","article-title":"Random Forests","volume":"45","author":"Breiman","year":"2001","journal-title":"Mach. Learn."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"871","DOI":"10.1029\/2018JE005592","article-title":"A New Global Database of Lunar Impact Craters > 1\u20132 km: 1. Crater Locations and Sizes, Comparisons with Published Databases, and Global Analysis","volume":"124","author":"Robbins","year":"2019","journal-title":"J. Geophys. Res. Planets"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"346","DOI":"10.1016\/j.icarus.2015.07.039","article-title":"A new lunar digital elevation model from the Lunar Orbiter Laser Altimeter and SELENE Terrain Camera","volume":"273","author":"Barker","year":"2016","journal-title":"Icarus"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1007\/s11214-009-9512-y","article-title":"The Lunar Orbiter Laser Altimeter Investigation on the Lunar Reconnaissance Orbiter Mission","volume":"150","author":"Smith","year":"2010","journal-title":"Space Sci. Rev."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1007\/s11214-010-9634-2","article-title":"Lunar Reconnaissance Orbiter Camera (LROC) Instrument Overview","volume":"150","author":"Robinson","year":"2010","journal-title":"Space Sci. Rev."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1016\/j.icarus.2014.02.022","article-title":"The variability of crater identification among expert and community crater analysts","volume":"234","author":"Robbins","year":"2014","journal-title":"Icarus"},{"key":"ref_44","first-page":"E03005","article-title":"Secondary craters of Tycho: Size-frequency distributions and estimated fragment size\u2013velocity relationships","volume":"111","author":"Hirata","year":"2006","journal-title":"J. Geophys. Res."},{"key":"ref_45","first-page":"E05006","article-title":"Mapping rays and secondary craters from the Martian crater Zunil","volume":"112","author":"Preblich","year":"2017","journal-title":"J. Geophys. Res."},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Wilhelms, D.E., Mccauley, J.F., and Trask, N.J. (1987). The Geologic History of the Moon, USGS Professional Paper 1348.","DOI":"10.3133\/pp1348"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"740","DOI":"10.1007\/s12583-015-0579-y","article-title":"Impact Craters with Circular and Isolated Secondary Craters on the Continuous Secondaries Facies on the Moon","volume":"26","author":"Zhou","year":"2015","journal-title":"J. Earth Sci."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"414","DOI":"10.1016\/j.icarus.2012.02.029","article-title":"The morphology of craters on Mercury: Results from MESSENGER flybys","volume":"219","author":"Barnouin","year":"2012","journal-title":"Icarus"},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Sammut, C., and Webb, G.I. (2010). Encyclopedia of Machine Learning, Springer. Springer reference.","DOI":"10.1007\/978-0-387-30164-8"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"015017","DOI":"10.1117\/1.JRS.10.015017","article-title":"Land cover and land use mapping of the iSimangaliso Wetland Park, South Africa: Comparison of oblique and orthogonal random forest algorithms","volume":"10","author":"Bassa","year":"2016","journal-title":"J. Appl. Remote Sens."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1016\/j.geomorph.2014.07.020","article-title":"Random Forest with semantic tie points for classifying landforms and creating rigorous shaded relief representations","volume":"224","author":"Veronesi","year":"2014","journal-title":"Geomorphology"},{"key":"ref_52","first-page":"130","article-title":"Decision tree methods: applications for classification and prediction","volume":"27","author":"Song","year":"2015","journal-title":"Shanghai Arch. Psychiatry"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1007\/BF00116251","article-title":"Induction of decision trees","volume":"1","author":"Quinlan","year":"1986","journal-title":"Mach. Learn."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"372","DOI":"10.1007\/s11633-010-0517-5","article-title":"Improving Decision Tree Performance by Exception Handling","volume":"7","author":"Subramanian","year":"2010","journal-title":"Int. J. Autom. Comput."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1198\/tast.2009.08199","article-title":"Variable Importance Assessment in Regression: Linear Regression versus Random Forest","volume":"63","year":"2009","journal-title":"Am. Stat."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1037\/a0016973","article-title":"An introduction to recursive partitioning: Rationale, application, and characteristics of classification and regression trees, bagging, and random forests","volume":"14","author":"Strobl","year":"2009","journal-title":"Psychol. Methods"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"2225","DOI":"10.1016\/j.patrec.2010.03.014","article-title":"Variable selection using random forests","volume":"31","author":"Genuer","year":"2010","journal-title":"Pattern Recognit. Lett."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"159","DOI":"10.2307\/2529310","article-title":"The Measurement of Observer Agreement for Categorical Data","volume":"33","author":"Landis","year":"1977","journal-title":"Biometrics"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/21\/2594\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:32:06Z","timestamp":1760189526000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/11\/21\/2594"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,11,5]]},"references-count":58,"journal-issue":{"issue":"21","published-online":{"date-parts":[[2019,11]]}},"alternative-id":["rs11212594"],"URL":"https:\/\/doi.org\/10.3390\/rs11212594","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,11,5]]}}}