{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T22:06:00Z","timestamp":1782597960017,"version":"3.54.5"},"reference-count":88,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,19]],"date-time":"2020-06-19T00:00:00Z","timestamp":1592524800000},"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>Volcanic-aeolian interactions and processes have played a vital role in landscape evolution on Mars. Martian lava fields and associated caves have extensive geomorphological, astrobiological, and in-situ resource utilization (ISRU) implications for future Mars missions which might be focused on subsurface exploration. Although several possible cave \u201cskylights\u201d of tens to &gt;100 m diameter have been spotted in lava fields of Mars, there is a possibility of prevalence of meter-scale features which are an order of magnitude smaller and difficult to identify but could have vital significance from the scientific and future exploration perspectives. The Icelandic volcanic-aeolian environment and fissure volcanoes can serve as analogs to study lava flow-related small caves such as surface tubes, inflationary caves, liftup caves, and conduits. In the present work, we have tried to explore the usability of unmanned aerial vehicle (UAV)-derived images for characterizing a solidified lava flow and designing a sequential methodology to identify small caves in the lava flow. In the mapped area of ~0.33 km2, we were able to identify 81 small cave openings, five lava flow morphologies, and five small cave types using 2 cm\/pixel high-resolution images. The results display the usefulness of UAV imaging for such analogous research, and also highlight the possibility of the widespread presence of similar small cave openings in Martian lava fields. Such small openings can facilitate optimal air circulation within the caves while sheltering the insides from physical weathering and harmful radiations. Using the available best resolution remote sensing images, we extend the analogy through the contextual and geomorphological analysis of several possible pit craters in the Tharsis region of Mars, in a region of extremely vesicular and fragile lava crust with pahoehoe-type morphology. We report two possible pit craters in this region, with diameters as small as ~20 m. The possibility that such small cave openings can lead to vast subterranean hollow spaces on Mars cannot be ruled out considering its low gravity.<\/jats:p>","DOI":"10.3390\/rs12121970","type":"journal-article","created":{"date-parts":[[2020,6,19]],"date-time":"2020-06-19T10:43:58Z","timestamp":1592563438000},"page":"1970","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Small Lava Caves as Possible Exploratory Targets on Mars: Analogies Drawn from UAV Imaging of an Icelandic Lava Field"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3181-2960","authenticated-orcid":false,"given":"Lydia","family":"Sam","sequence":"first","affiliation":[{"name":"Division of Space Technology, Department of Computer Science, Electrical and Space Engineering, Lule\u00e5 University of Technology, 97187 Lule\u00e5, Sweden"},{"name":"School of Geosciences, University of Aberdeen, Meston Building, King\u2019s College, Aberdeen AB24 3UE, UK"},{"name":"National Space Science and Technology Center, United Arab Emirates University, P.O. Box 15551, Al Ain, Abu Dhabi, UAE"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2502-6384","authenticated-orcid":false,"given":"Anshuman","family":"Bhardwaj","sequence":"additional","affiliation":[{"name":"Division of Space Technology, Department of Computer Science, Electrical and Space Engineering, Lule\u00e5 University of Technology, 97187 Lule\u00e5, Sweden"},{"name":"School of Geosciences, University of Aberdeen, Meston Building, King\u2019s College, Aberdeen AB24 3UE, UK"},{"name":"National Space Science and Technology Center, United Arab Emirates University, P.O. Box 15551, Al Ain, Abu Dhabi, UAE"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4304-388X","authenticated-orcid":false,"given":"Shaktiman","family":"Singh","sequence":"additional","affiliation":[{"name":"Division of Space Technology, Department of Computer Science, Electrical and Space Engineering, Lule\u00e5 University of Technology, 97187 Lule\u00e5, Sweden"},{"name":"School of Geosciences, University of Aberdeen, Meston Building, King\u2019s College, Aberdeen AB24 3UE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6479-2236","authenticated-orcid":false,"given":"F. Javier","family":"Martin-Torres","sequence":"additional","affiliation":[{"name":"Division of Space Technology, Department of Computer Science, Electrical and Space Engineering, Lule\u00e5 University of Technology, 97187 Lule\u00e5, Sweden"},{"name":"School of Geosciences, University of Aberdeen, Meston Building, King\u2019s College, Aberdeen AB24 3UE, UK"},{"name":"Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Armilla, 18100 Granada, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4492-9650","authenticated-orcid":false,"given":"Maria-Paz","family":"Zorzano","sequence":"additional","affiliation":[{"name":"Division of Space Technology, Department of Computer Science, Electrical and Space Engineering, Lule\u00e5 University of Technology, 97187 Lule\u00e5, Sweden"},{"name":"Centro de Astrobiolog\u00eda (INTA-CSIC), 28850 Torrej\u00f3n de Ardoz, Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juan Antonio","family":"Ram\u00edrez Luque","sequence":"additional","affiliation":[{"name":"Division of Space Technology, Department of Computer Science, Electrical and Space Engineering, Lule\u00e5 University of Technology, 97187 Lule\u00e5, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"887","DOI":"10.1089\/ast.2014.1227","article-title":"A new analysis of Mars \u201cSpecial Regions\u201d: Findings of the second MEPAG Special Regions Science Analysis Group (SR-SAG2)","volume":"14","author":"Rummel","year":"2014","journal-title":"Astrobiology"},{"key":"ref_2","unstructured":"Sam, L., Bhardwaj, A., Singh, S., and Martin-Torres, F.J. 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