{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,26]],"date-time":"2026-01-26T02:24:31Z","timestamp":1769394271611,"version":"3.49.0"},"reference-count":38,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,16]],"date-time":"2023-09-16T00:00:00Z","timestamp":1694822400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The remnants of explosive volcanism on Mercury have been observed in the form of vents and pyroclastic deposits, termed faculae, using data from the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) onboard the Mercury surface, space environment, geochemistry, and ranging (MESSENGER) spacecraft. Although these features present a wide variety of sizes, shapes, and spectral properties, the large number of observations and the lack of high-resolution hyperspectral images complicates their detailed characterisation. We investigate the application of unsupervised deep learning to explore the diversity and constrain the extent of the Hermean pyroclastic deposits. We use a three-dimensional convolutional autoencoder (3DCAE) to extract the spectral and spatial attributes that characterise these features and to create cluster maps constructing a unique framework to compare different deposits. From the cluster maps we define the boundaries of 55 irregular deposits covering 110 vents and compare the results with previous radius and surface estimates. We find that the network is capable of extracting spatial information such as the border of the faculae, and spectral information to altogether highlight the pyroclastic deposits from the background terrain. Overall, we find the 3DCAE an effective technique to analyse sparse observations in planetary sciences.<\/jats:p>","DOI":"10.3390\/rs15184560","type":"journal-article","created":{"date-parts":[[2023,9,17]],"date-time":"2023-09-17T23:32:27Z","timestamp":1694993547000},"page":"4560","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Deep Learning Investigation of Mercury\u2019s Explosive Volcanism"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1329-6459","authenticated-orcid":false,"given":"Mireia","family":"Leon-Dasi","sequence":"first","affiliation":[{"name":"LESIA, Observatoire de Paris, Universit\u00e9 PSL, CNRS, 5 Place Jules Janssen, 92195 Meudon, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1052-5439","authenticated-orcid":false,"given":"Sebastien","family":"Besse","sequence":"additional","affiliation":[{"name":"European Space Agency (ESA), European Space Astronomy Centre (ESAC), Camino Bajo del Castillo s\/n, Villanueva de la Ca\u00f1ada, 28692 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8652-7919","authenticated-orcid":false,"given":"Alain","family":"Doressoundiram","sequence":"additional","affiliation":[{"name":"LESIA, Observatoire de Paris, Universit\u00e9 PSL, CNRS, 5 Place Jules Janssen, 92195 Meudon, France"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1126\/science.1159256","article-title":"Volcanism on Mercury: Evidence from the First MESSENGER Flyby","volume":"321","author":"Head","year":"2008","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1016\/j.epsl.2009.04.037","article-title":"Explosive volcanic eruptions on Mercury: Eruption conditions, magma volatile content, and implications for interior volatile abundances","volume":"285","author":"Kerber","year":"2009","journal-title":"Earth Planet. 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