Journal of Geophysical Research: Planets最新文献

{"title":"Geological Characteristics of Floor-Fractured Craters in the Central Noachis Terra, Mars: Implications for Post-Noachian Habitable Environment","authors":"Yuan Zhao,&nbsp;Jiannan Zhao,&nbsp;Ting Huang,&nbsp;Long Xiao","doi":"10.1029/2025JE009441","DOIUrl":"https://doi.org/10.1029/2025JE009441","url":null,"abstract":"<p>Floor-fractured craters (FFCs) are unique impact structures characterized by extensive fractures and uplifted floors, often associated with intrusive volcanic activity or potential aqueous processes. This study investigates a cluster of FFCs in central Noachis Terra, Mars, including Asimov, Maunder, and two unnamed craters to elucidate their geological characteristics and formation mechanisms. Using high-resolution imagery, topographic data, and spectral analyses, we mapped three types of fractures and identified various landforms that may indicate past glacial activity, such as viscous flow features and polygonized textures, and candidate features that may indicate contemporary aqueous activity, such as gullies and recurring slope lineae. Mineralogical analyses revealed the presence of saponite and Mg- and Fe-smectite within fractures, suggesting prolonged aqueous alteration. Age determination through crater counting indicates that the Maunder crater formed around 3.66 Ga (early Hesperian). We propose a hypothesis that the FFCs possibly originated from intrusive volcanism activated by the long-lived structural inheritance of Hellas and Argyre basin impacts that retriggered by the young impact event of Maunder, with subsequent groundwater activity and glacial modification expanding the fractures. The existence of possible water/ice-related landforms and aqueous minerals highlights the FFCs as hubs of hydrological activity and potential sites for past and present habitability. These results underscore the importance of FFCs as critical targets for future missions aiming to explore Mars' post-Noachian climate transitions and habitable environment.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intra-Tessera Plains: Implications of Their Radar Properties for Surface Processes on Venus","authors":"E. N. Haas,&nbsp;J. L. Whitten","doi":"10.1029/2025JE009147","DOIUrl":"https://doi.org/10.1029/2025JE009147","url":null,"abstract":"<p>Intra-tessera plains are radar-dark plains deposits that occur within tesserae. Their emplacement mechanism(s) and composition are poorly constrained, though they are hypothesized to be basaltic lava flows. Here, we map intra-tessera plains within 16 different tesserae spanning various latitudes and elevations. Intra-tessera plains have three dominant geologic units (regional plains, shield plains, and smooth plains) which we compare with morphologically similar lowland plains, and plains that overlap with known parabolic ejecta deposits, to better constrain the ability of these ejecta to modify surface signatures in synthetic aperture radar data. We examine the Magellan radar backscatter, emissivity, and altimetry data of all mapped intra-tessera plains, lowland plains, and parabolic ejecta study regions. Our results support the observation that parabolic ejecta deposits modify the backscatter coefficients of intra-tessera plains and lowland plains by smoothing these materials, while variations in the radar properties caused by differences in plains geologic units are minimal. Conversely, there are clear differences in the backscatter coefficients and emissivity of high- and low-elevation intra-tessera and lowland plains. Our mapped intra-tessera plains follow six different elevation–emissivity patterns. Regardless of which pattern is observed, intra-tessera plains mimic the radar behavior of the tesserae in which they occur. This parallel behavior suggests that the same processes are affecting both terrains, placing constraints on proposed high reflectivity formation mechanisms. While multiple hypotheses remain plausible, our data are most consistent with the atmospheric deposition of metallic frost.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JE009147","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact-Driven Cr-Fe-O Vaporization and Deposition on the Moon","authors":"Xiaojia Zeng,&nbsp;Chenkun Sun,&nbsp;Mingchao Xiong,&nbsp;Xiongyao Li","doi":"10.1029/2026JE009807","DOIUrl":"https://doi.org/10.1029/2026JE009807","url":null,"abstract":"<p>Hypervelocity impacts from micrometeorites or asteroids are a dominant long-term geological process that modifies the mineralogical and elemental components of surface regolith on the Moon and other airless planetary bodies. However, the pathways by which impacts drive elemental redistribution on the Moon remain poorly understood. Here, we report the discovery of thousands of chromite (FeCr₂O₄) nanoparticles deposited on a space-weathered olivine fragment from Chang'e−5 lunar regolith. These chromite nanoparticles display morphological and textural characteristics consistent with vapor-phase condensation rather than magmatic crystallization. We therefore propose that the deposited chromite nanoparticles formed via localized vaporization of Cr, Fe, and O from lunar regolith during hypervelocity impacts, followed by rapid condensation and deposition. This study provides direct mineralogical evidence for impact-driven Cr-Fe-O vaporization and deposition, offering new insights into the elemental cycling and regolith evolution on the Moon and other airless bodies.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Subsurface Temperatures, Thermal Gradient, and Thermal Wave Propagation Depth Constrained Using Thermoluminescence of the Apollo 17 Deep Drill Core","authors":"Alexander Sehlke,&nbsp;Derek W. G. Sears,&nbsp;H. H. Schmitt,&nbsp;the ANGSA Science Team","doi":"10.1029/2026JE009720","DOIUrl":"https://doi.org/10.1029/2026JE009720","url":null,"abstract":"<p>We measured the natural thermoluminescence (TL) levels of Apollo 17 deep drill core samples between depths of 95 and 291 cm, and derived the temperatures at which the TL signal had equilibrated. We used TL glow curve deconvolution as our primary method to determine the natural TL in these samples. A total of five discrete TL peaks is required to adequately fit the measured glow curves. Using the lowest-temperature peak, we found that equilibrium temperatures increase systematically with depth, corresponding to a temperature gradient of 1.0 ± 0.5 K m⁻¹ at an average of 248 ± 14 K between depths of 133 and 291 cm. Moreover, we found evidence that the sample at a depth of 95 cm is affected by long-term (annual) thermal cycles and suggest that this thermal wave propagation depth does not exceed 135 cm. Our results align well with the in situ thermal probe measurements. We conclude that TL glow curve deconvolution of bulk samples with complex mineralogy, such as lunar regolith, is a valid approach for analyzing TL glow curves, and secondly, that TL may serve as an alternative method for determining the thermal structure of the lunar subsurface regolith.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Species-Dependent Tidal Effects on Ions in the Martian Upper Atmosphere","authors":"Menghao Fu,&nbsp;Hao Gu,&nbsp;Jun Cui,&nbsp;Tielong Zhang,&nbsp;Mingyu Wu","doi":"10.1029/2026JE009803","DOIUrl":"https://doi.org/10.1029/2026JE009803","url":null,"abstract":"&lt;p&gt;Atmospheric tides drive large-scale variability in the Martian ionosphere, but their effect on ionospheric composition remains unclear. Using measurements from the Neutral Gas and Ion Mass Spectrometer (NGIMS) onboard the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission, we examine tidal signatures in the major ions &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mtext&gt;CO&lt;/mtext&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${text{CO}}_{2}^{+}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;O&lt;/mi&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${mathrm{O}}_{2}^{+}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;, with emphasis on species-dependent behavior and chemical coupling. Harmonic analysis of zonal wavenumbers 1–3 reveals strong tidal amplitudes, up to ∼30%, between 150 and 200 km, with clear dependence on altitude, spatial scale, and season. Similar variability in the ion ratio suggests that tides may influence ionospheric composition beyond simple vertical displacements. The observed correspondence between tidal variations in the neutral O/&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msub&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;C&lt;/mi&gt;\u0000 &lt;mi&gt;O&lt;/mi&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;/msub&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${mathrm{C}mathrm{O}}_{2}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; ratio and in &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;O&lt;/mi&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;+&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt; ${mathrm{O}}_{2}^{+}$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;/&lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mi&gt;C&lt;/mi&gt;\u0000 &lt;mi&gt;O&lt;/mi&gt;\u0000 &lt;/mrow&gt;","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Ferrous and Ferric Iron on the Viscosity and Structure of Peridotitic Melts: Implication for Viscosity of Basal Magma Ocean in Mars","authors":"Yoshio Kono,&nbsp;Mizuho Sakurahara,&nbsp;Chihiro Koyama,&nbsp;Ryoichi Nakada,&nbsp;Nozomi M. Kondo,&nbsp;Steeve Gréaux,&nbsp;Hideharu Kuwahara,&nbsp;Koji Ohara,&nbsp;Yuki Watanabe,&nbsp;Hirohisa Oda,&nbsp;Takehiko Ishikawa","doi":"10.1029/2026JE009944","DOIUrl":"https://doi.org/10.1029/2026JE009944","url":null,"abstract":"<p>Oxidation state of magma ocean is one of the most important factors, which influence its nature and dynamics. Since iron is the most abundant redox-sensitive element, understanding the effect of ferrous (Fe²⁺) and ferric (Fe³⁺) iron on the physical properties and structure of peridotite melts are fundamental to discuss geophysical and geochemical evolutions of magma ocean. In this study, we investigate the viscosity of Fe³⁺-bearing peridotitic melts under Ar gas environment by utilizing an electrostatic levitation furnace at the International Space Station. The results show strong increase of the viscosity of the Fe³⁺-bearing peridotitic melts with increasing iron content, which is in contrast to previous reports of lower viscosities of iron-abundant peridotitic melts than iron-poor peridotitic melts under reduced environment. Our structural investigations show that Fe³⁺ causes polymerization of melt structure with increasing iron content, while Fe²⁺-dominant peridotitic melts under reduced environment show almost no change in the melt structure. These results indicate that polymerization of melt structure by Fe³⁺ strongly increases the viscosity of peridotitic melt, while simple replacement of Mg²⁺ with Fe²⁺ decreases the viscosity of peridotitic melt. Since deep magma ocean is considered to be enriched in Fe³⁺, due to disproportionation reaction to form metallic iron and Fe³⁺ at high pressures, strong increase of the viscosity of peridotitic melt by the formation of Fe³⁺ would be important to discuss nature and dynamics of magmas at deep planetary interiors, such as formation and stability of the basal magma ocean at the core-mantle boundary in Mars.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inferring Io's Internal Properties by Combining Gravity Measurements and Volcanic Activity","authors":"A. Veenstra,&nbsp;M. Rovira-Navarro,&nbsp;W. van der Wal","doi":"10.1029/2026JE009885","DOIUrl":"https://doi.org/10.1029/2026JE009885","url":null,"abstract":"<p>With its extreme geological activity, Io represents an archetype for tidally heated exoplanets/moons and provides insight into early stages of terrestrial planet evolution. Decades of ground-based observations and multiple space missions have refined our understanding of Io, yet it remains debated where inside Io the tidal heating takes place. Here, we synthesize several independent data sets in a Bayesian approach to provide an updated view of Io's interior. Tidal response data constrain the bulk mechanical properties of the silicate envelope but do not resolve the radial profile. We propose adding constraints based on the observed distribution of volcanic activity, thereby introducing sensitivity to the radial viscosity profile. The combined observations are consistent with the majority of the dissipation occurring in a low-viscosity asthenosphere approximately 200 km thick, with a maximum viscosity of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>∼</mo>\u0000 <mn>1</mn>\u0000 <msup>\u0000 <mn>0</mn>\u0000 <mn>14</mn>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${sim} 1{0}^{14}$</annotation>\u0000 </semantics></math> Pa s, which is also valid under a more conservative estimate of spatially uniform heat flux. This low viscosity implies either enhanced viscous dissipation under Io's conditions due to poorly understood rheological laws, an asthenosphere near the disaggregation threshold, corresponding to a melt fraction of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>&gt;</mo>\u0000 <mn>30</mn>\u0000 <mi>%</mi>\u0000 </mrow>\u0000 <annotation> ${ &gt;} 30%$</annotation>\u0000 </semantics></math>, or a combination of both. Together, these results provide a coherent interior structure and thermal state that can be used in future Io studies.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JE009885","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cross-Hemisphere Impacts of Dust Tides on the Martian Atmosphere During the Mars Year 34 Global Dust Storm","authors":"Yueming Cheng,&nbsp;Zhaopeng Wu,&nbsp;Yuan Lian,&nbsp;Jun Cui,&nbsp;Yong Wei","doi":"10.1029/2025JE009550","DOIUrl":"https://doi.org/10.1029/2025JE009550","url":null,"abstract":"<p>Airborne dust plays a fundamental role in controlling the Martian atmospheric circulation by modulating radiative heating and wave excitation. While previous studies attributed the strengthening and poleward extension of the cross-equatorial Hadley circulation during dust storms to the overall increase in atmospheric dust loading, the influence of diurnal dust variations (dust tides) has not been explored. Using the general circulation model with prescribed dust distributions, this study investigates the influence of dust tides on global-scale atmospheric dynamics during the mature stage of the MY34 global dust event. The results demonstrate that dust tides substantially intensify and extend the cross-equatorial Hadley circulation, leading to a stronger north polar warming. A pronounced dust-tide-induced hemispheric difference exists. In the southern hemisphere, dust tides amplify the tidal components of temperature and winds. In the northern hemisphere, however, dust tides enhance the mean meridional circulation through wave–driven forcing on the mean flow. Hough mode analysis reveals that dust tides primarily strengthen the negative meridional-index components of the diurnal migrating tide, which dominate wave–driven forcing and connect diurnal dust radiative forcing to global circulation. These findings suggest that dust tides are an important dynamical mechanism that not only influences the coupling between regional radiative and tidal processes, but also affects the global transport of momentum and energy by affecting global circulations.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation Belt Electron Scattering by Chorus Waves in Jupiter's Magnetosphere","authors":"Peng Lu,&nbsp;Xing Cao,&nbsp;Xudong Gu,&nbsp;Binbin Ni,&nbsp;Wei Xu,&nbsp;Ruiqi Pan,&nbsp;Shaobei Wang,&nbsp;Minyi Long","doi":"10.1029/2026JE009958","DOIUrl":"https://doi.org/10.1029/2026JE009958","url":null,"abstract":"<p>Whistler-mode chorus waves are recognized as key drivers of both the acceleration and loss of radiation belt electrons in Jupiter's magnetosphere. In this study, we investigate the resonant interactions between chorus waves and radiation belt electrons at <i>L</i>-shell = 6–12, using a newly developed empirical wave model based on combined Galileo and Juno observations. Owing to a strong dawn-dusk asymmetry in wave power distribution, electron scattering rates due to duskside chorus waves are almost an order of magnitude stronger than those due to dawnside waves. By calculating the drift- and bounce-averaged electron diffusion coefficients, we model the temporal evolution of electrons at different <i>L</i>-shells using two-dimensional Fokker-Planck simulations. At <i>L</i>-shell = 6, chorus waves exert limited effects on electrons above 200 keV and reduce the flux of electrons below 200 keV by only one order of magnitude over 100 days. At <i>L</i>-shell ≥ 8, chorus waves can cause efficient scattering loss of &lt;∼MeV electrons and acceleration of higher energy electrons. The corresponding loss of lower energy electrons is found to be much more efficient than the acceleration of higher energy electrons. Furthermore, we investigate the influence of the initial energy spectrum on chorus wave-induced acceleration of radiation belt electrons. Our findings improve the current understanding of the role of chorus waves in the dynamics of Jupiter's radiation belts.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148942130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping Scalloped Terrains on Mars at the Meter Scale","authors":"Yiran Wang,&nbsp;Miao Zhuo,&nbsp;Zhaoran Wei,&nbsp;Miaosen Xia,&nbsp;Jiannan Zhao","doi":"10.1029/2026JE009764","DOIUrl":"https://doi.org/10.1029/2026JE009764","url":null,"abstract":"<p>Scalloped terrains are a kind of periglacial landform, shaped by permafrost evolution that involves degradation of near-surface excess ice, and are mostly distributed in the mid-latitudes of Mars. Their evolution mechanism remains debated, including whether liquid water was involved (thermokarst-lake vs. sublimation) and what the ice-rich precursor conditions were (pre-existing vs. post-deposited volatiles). Therefore, studies on scalloped terrains can provide important clues to the distribution and abundance of local water ice, as well as the climatic evolution of late Amazonian Mars. However, their hemispheric-scale distribution has remained poorly constrained. In this study, we develop a deep-learning semantic segmentation framework to map scalloped terrains across the northern hemisphere of Mars using the global CTX mosaic. The model achieves high accuracy, enabling reliable pixel-level identification of isolated, coalesced, and degraded forms. On this basis, we generate and publicly release a 5-m-per-pixel hemispheric-wide map of scalloped terrains and analyze their distribution, density and orientation. The results reveal a concentration of scalloped terrains in Utopia Planitia and a systematic latitudinal trends in depression types, most notably a transition from isolated depressions at 42°–45°N to increasingly coalesced and boundary-less terrain beyond 48°N, reflecting the distribution of near-surface ice-rich deposits. Orientation analysis further reveals the influence of geomorphologic context on the growth and degradation of scalloped terrains in addition to insolation condition. These findings provide new quantitative constraints on the evolution of Martian periglacial landforms and establish a scalable framework for automated planetary geomorphologic mapping.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"131 9","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148849022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}