Journal of Geophysical Research: Planets最新文献

{"title":"Moment of Inertia and Tectonic Record of Asteroid 16 Psyche May Reveal Interior Structure and Core Solidification Processes","authors":"Fiona Nichols-Fleming,&nbsp;Alexander J. Evans,&nbsp;Brandon C. Johnson,&nbsp;Michael M. Sori","doi":"10.1029/2024JE008291","DOIUrl":"https://doi.org/10.1029/2024JE008291","url":null,"abstract":"<p>The thermal and chemical evolution of (16) Psyche would have been influenced by the direction of core solidification and thickness of an outer (rocky) silicate layer. We model the thermal evolution and core solidification of Psyche for a range of outer silicate layer thicknesses and core sulfur contents to calculate the resulting radial contraction and moments of inertia. We generally find that increasing the thickness of the outer silicate layer by 10 km results in a ∼1-km reduction in total radial contraction. Additionally, we find that the timing of full core solidification, and thus a large amount of predicted contraction, can differ by up to 25 Myr for inward versus outward core growth. Finally, our calculated moment-of-inertia factors for models with inward core growth that contain sulfur are consistently larger than those with outward core growth. Ultimately, spacecraft-derived estimates of Psyche's moment of inertia and surface contraction will be able to provide constraints on Psyche's interior evolution, silicate layer thickness, and direction of core solidification.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141488574","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":"Mantle Mineralogy of Reduced Sub-Earths Exoplanets and Exo-Mercuries","authors":"Camilla Cioria,&nbsp;Giuseppe Mitri,&nbsp;James Alexander Denis Connolly,&nbsp;Jean-Philippe Perrillat,&nbsp;Fabrizio Saracino","doi":"10.1029/2023JE008234","DOIUrl":"https://doi.org/10.1029/2023JE008234","url":null,"abstract":"<p>The mineralogy of planetary mantles formed under reducing conditions, as documented in the inner regions of the solar system, is not well constrained. We present thermodynamic models of mineral assemblages that would constitute the mantles of exo-Mercuries. We investigated reduced materials such as enstatite chondrites, CH, and CB chondrites, and aubrites, as precursor bulk compositions in phase equilibrium modeling. The resulting isochemical phase diagram sections indicate that dominant phases in these reduced mantles would be pyroxenes rather than olivine, contrasting with the olivine-rich mantles found within Earth, Mars, and Venus. The pyroxene abundances in the modeled mantles assemblages depend on the silica content shown by precursor materials. The silica abundance in the mantle is closely related to Si abundance in the core, particularly in reduced environments. In addition, we propose that pyroxene-rich mantles exhibit more vigorous convective and tectonic activity than olivine-rich mantles, given that pyroxene-rich mantles would have lower viscosity and a lower solidus temperature (<i>Ts</i>).</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141488291","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":"Dome Craters on Ganymede and Callisto May Form by Topographic Relaxation of Pit Craters Aided by Remnant Impact Heat","authors":"M. L. Caussi,&nbsp;A. J. Dombard,&nbsp;D. G. Korycansky,&nbsp;O. L. White,&nbsp;J. M. Moore,&nbsp;P. M. Schenk","doi":"10.1029/2023JE008258","DOIUrl":"https://doi.org/10.1029/2023JE008258","url":null,"abstract":"<p>The icy Galilean satellites display impact crater morphologies that are rare in the Solar System. They deviate from the archetypal sequence of crater morphologies as a function of size found on rocky bodies and other icy satellites: they exhibit central pits in place of peaks, followed by central dome craters, anomalous dome craters, penepalimpsests, palimpsests, and multi-ring structures. Understanding the origin of these features will provide insight into the geophysical factors that operate within the icy Galilean satellites. Pit craters above a size threshold feature domes. This trend, and the similarity in morphology between the two classes, suggest a genetic link between pit and dome craters. We propose that dome craters evolve from pit craters through topographic relaxation, facilitated by remnant heat from the impact. Our finite element simulations show that, for the specific crater sizes where we see domes on Ganymede and Callisto, domes form from pit craters within 10 Myr. Topographic relaxation eliminates the stresses induced by crater topography and restores a flat surface: ice flows downwards from the rim and upwards from the crater depression driven by gravity. When the starting topography is a pit crater, the heat left over from the impact is concentrated below the pit. Since warm ice flows more rapidly, the upward flow is enhanced beneath the pit, leading to the emergence of a dome. Given the timescales and the dependence on heat flux, this model could be used to constrain the thermal history and evolution of these moons.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008258","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141488290","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":"Evaluating the Use of Seasonal Surface Displacements and Time-Variable Gravity to Constrain the Interior of Mars","authors":"N. L. Wagner,&nbsp;P. B. James,&nbsp;A. I. Ermakov,&nbsp;M. M. Sori","doi":"10.1029/2023JE008053","DOIUrl":"https://doi.org/10.1029/2023JE008053","url":null,"abstract":"<p>The mass transport of volatiles on Mars represents a seasonally changing load on the surface of the planet. Like on Earth, as mass is redistributed across the planet, the surface responds in a complex manner becoming displaced downwards or upwards. The magnitude and extent of displacement depend on the properties of the load and mechanical properties of the planetary interior. Based on new estimates of the height variation of the seasonal polar caps (SPCs), we predict local surface displacements of up to tens of millimeters with a strong degree 1 signal throughout the Martian year. The long-wavelength portion of the displacement is potentially observable, with a magnitude of a few millimeters, located away from the SPC where one could realistically measure it with a landed or orbital mission. We also model the direct contribution of this process to observable time variable gravity, where we find the zonal coefficients to be in line with previous measurements, although with a smaller magnitude. Future measurements of this displacement could be used to help elucidate the composition of the interior of Mars using this process as a probe into the Martian interior. Furthermore, more refined measurements of time-variable gravity would be a powerful tool in constraining the pole-to-pole volatile cycle present on Mars.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008053","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141488679","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":"Sustaining Hydrothermal Circulation With Gravity Relevant to Ocean Worlds","authors":"A. T. Fisher,&nbsp;K. L. Dickerson,&nbsp;D. K. Blackman,&nbsp;N. G. Randolph-Flagg,&nbsp;C. R. German,&nbsp;C. Sotin","doi":"10.1029/2023JE008202","DOIUrl":"https://doi.org/10.1029/2023JE008202","url":null,"abstract":"<p>Some ocean worlds may sustain active, seafloor hydrothermal systems, but the characteristics and controls on fluid-heat transport in these systems are not well understood. We developed three-dimensional numerical simulations, using a ridge-flank hydrothermal system on Earth as a reference, to test the influence of ocean world gravity on fluid and heat transport. Simulations represented the upper ∼4–5 km below the seafloor and explored ranges of: heat input at the base, aquifer thickness, depth, and permeability, and gravity values appropriate for Earth, Europa, and Enceladus. We tested when a hydrothermal siphon could be sustained and quantified consequent circulation temperatures, flow rates, and advective heat output. Calculations illustrate a trade-off in energy between the reduction of buoyancy at lower gravity, which tends to reduce the primary forces driving fluid circulation, and the concomitant reduction in secondary convection, which consumes available energy. When a siphon was sustained under lower gravity, circulation temperatures tended to increase modestly (which should lead to more extensive geochemical reactions), whereas mass flow rates and advective heat output tended to be reduced. Deeper subseafloor circulation resulted in higher temperatures and flow rates, with a deeper, thin aquifer being more efficient in removing heat from the rocky interior. Water-rock ratios were lower when gravity was lower, as was the efficiency of heat extraction, whereas the time required to circulate the volume of an ocean-world's ocean through the seafloor increased. This may help to explain how small ocean worlds could sustain hydrothermal circulation for a long time despite limited heat sources.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008202","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141488728","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":"Magma Chamber Depressurization and the Creation of Concentric Graben and Late-Stage Flow Units at Sapas Mons, Venus","authors":"Sean T. O’Hara,&nbsp;Patrick J. McGovern,&nbsp;Danielle vonLembke","doi":"10.1029/2023JE008134","DOIUrl":"https://doi.org/10.1029/2023JE008134","url":null,"abstract":"<p>Sapas Mons is a large shield volcano in Atla Regio on Venus. Its summit region is partially encircled by a system of pits and extensional faults (graben). The existence and configuration of this system have been attributed to stresses generated above the margin of a magma chamber spanning the region beneath the summit. The proposed stress-generating mechanism includes either withdrawal of magma from or solidification of magma within such a chamber (Keddie &amp; Head, 1994, https://doi.org/10.1007/bf00644896). To explore these hypotheses, we calculate Finite Element Method models of stresses and deformations resulting from magma chamber depressurization beneath a Sapas Mons-sized edifice with axisymmetric geometry. For a range of magma chamber depths and vertical thicknesses, we determine the minimum under pressure that produces a stress state predicting failure in circumferential normal mode at the observed position of the graben system. We also determine maximum under pressure under two conditions: (1) no failure (thrust fault mode) predicted at the summit, and (2) predicted failure (thrust fault mode) limited to within 10 km of the summit. We find that successful models require sill-like chamber geometry with vertical thicknesses &lt;1.5 km (diameter to thickness aspect ratios &gt;66:1), and chamber depth &lt;8 km beneath the summit. Calculated reductions in chamber volume are comparable to volumes of late-stage eruptive units mapped at Sapas Mons, favoring the magma withdrawal hypothesis for graben system formation. Evidence that unit 5 of Keddie and Head (1994, https://doi.org/10.1007/bf00644896) overlapped in time with, but largely postdated, the graben forming event renders it the most likely destination for magma removed from the chamber.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141441330","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":"Quantifying Shock Effects of Mars Sample via Micro-FTIR Spectra of Plagioclase","authors":"Wen Yu,&nbsp;Xiaojia Zeng,&nbsp;Xiongyao Li,&nbsp;Hong Tang,&nbsp;Jianzhong Liu","doi":"10.1029/2024JE008487","DOIUrl":"https://doi.org/10.1029/2024JE008487","url":null,"abstract":"<p>Precisely constraining the shock pressure of a Mars sample is critical for revealing the shock condition, geological process, and habitability of the Martian surface. The crystal structure of plagioclase is sensitive to the moderate shock pressure, such that its infrared spectra may record the shock state of Martian materials. In this study, we present a new way for quantifying the shock pressure via the micro-FTIR spectra of plagioclase by re-analyzing the published spectra of experimental shocked feldspars. Using the absorption area of micro-FTIR in the range of ∼1,000–1,150 cm⁻¹, the shock pressures of plagioclases from three types of Mars meteorites were constrained. The results show that the nakhlite Northwest Africa (NWA) 10645, shergottite Tindouf 002, and martian breccia NWA 11220 have the shock pressure of 18.5 ± 5.2 GPa, &gt;30 GPa, and 0–24.2 GPa, respectively. Our work demonstrates that the micro-FTIR spectra of plagioclase is not only a quantitative tool for constraining the moderate shock pressure (&lt;30 GPa) of Martian materials but also a useful technique for recognizing the high-pressure phase maskelynite from plagioclase-glass and evaluating the shock effects of Mars samples. In the future, this method will be available for the analysis of Mars samples returned by China's Tianwen-3 mission in around 2030.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141439629","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":"Temperature and Composition Disturbances in the Southern Auroral Region of Jupiter Revealed by JWST/MIRI","authors":"Pablo Rodríguez-Ovalle,&nbsp;Thierry Fouchet,&nbsp;Sandrine Guerlet,&nbsp;Thibault Cavalié,&nbsp;Vincent Hue,&nbsp;Manuel López-Puertas,&nbsp;Emmanuel Lellouch,&nbsp;James A. Sinclair,&nbsp;Imke de Pater,&nbsp;Leigh N. Fletcher,&nbsp;Michael H. Wong,&nbsp;Jake Harkett,&nbsp;Glenn S. Orton,&nbsp;Ricardo Hueso,&nbsp;Agustín Sánchez-Lavega,&nbsp;Tom S. Stallard,&nbsp;Dominique Bockelee-Morvan,&nbsp;Oliver King,&nbsp;Michael T. Roman,&nbsp;Henrik Melin","doi":"10.1029/2024JE008299","DOIUrl":"https://doi.org/10.1029/2024JE008299","url":null,"abstract":"<p>Jupiter's South Polar Region (SPR) was observed by James Webb Space Telescope/Mid-Infrared Instrument in December 2022. We used the Medium Resolution Spectrometer mode to provide new information about Jupiter's South Polar stratosphere. The southern auroral region was visible and influenced the atmosphere in several ways: (a) In the interior of the southern auroral oval, we retrieved peak temperatures at two distinct pressure levels near 0.01 and 1 mbar, with warmer temperatures with respect to non-auroral regions of 12 ± 2 K and 37 ± 4 K respectively. A cold polar vortex is centered at 65°S at 10 mbar. (b) We found that the homopause is elevated to <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msubsup>\u0000 <mn>590</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>118</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mo>+</mo>\u0000 <mn>25</mn>\u0000 </mrow>\u0000 </msubsup>\u0000 </mrow>\u0000 <annotation> ${590}_{-118}^{+25}$</annotation>\u0000 </semantics></math> km above the 1-bar pressure level inside the auroral oval compared to <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msubsup>\u0000 <mn>460</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>50</mn>\u0000 </mrow>\u0000 <mrow>\u0000 <mo>+</mo>\u0000 <mn>60</mn>\u0000 </mrow>\u0000 </msubsup>\u0000 </mrow>\u0000 <annotation> ${460}_{-50}^{+60}$</annotation>\u0000 </semantics></math> km at neighboring latitudes and with an upper altitude of 350 km in regions not affected by auroral precipitation. (c) The retrieved abundance of C₂H₂ shows an increase within the auroral oval, and it exhibits high abundances throughout the polar region. The retrieved abundance of C₂H₆ increases toward the pole, without being localized in the auroral oval, in contrast with previous analysis (Sinclair et al., 2018, https://doi.org/10.1016/j.icarus.2017.09.016). We determined that the warming at 0.01 mbar and the elevated homopause might be caused by the flux of charged particles depositing their energy in the SPR. The 1-mbar hotspot may arise from adiabatic heating resulting from auroral-driven downwelling. The cold region at 10 mbar may be caused by radiative cooling by stratospheric aerosols. The differences in spatial distribution seem to indicate that the hydrocarbons analyzed are affected differently by auroral precipitation.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435602","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":"EMM EMUS Observations of FUV Aurora on Mars: Dependence on Magnetic Topology, Local Time, and Season","authors":"Krishnaprasad Chirakkil,&nbsp;Robert J. Lillis,&nbsp;Justin Deighan,&nbsp;Michael S. Chaffin,&nbsp;Sonal K. Jain,&nbsp;David A. Brain,&nbsp;Matthew O. Fillingim,&nbsp;Raghuram Susarla,&nbsp;Greg Holsclaw,&nbsp;Xiaohua Fang,&nbsp;Nick M. Schneider,&nbsp;Hoor AlMazmi,&nbsp;Hessa AlMatroushi,&nbsp;Marko Gacesa,&nbsp;Nayla El-Kork,&nbsp;Ed Thiemann,&nbsp;Jasper S. Halekas","doi":"10.1029/2024JE008336","DOIUrl":"https://doi.org/10.1029/2024JE008336","url":null,"abstract":"<p>We present a comprehensive study of the nightside aurora phenomenon on Mars, utilizing observations from EMUS onboard Emirates Mars Mission. The oxygen emission at 130.4 nm is by far the brightest FUV auroral emission line observed at Mars. Our statistical analysis reveals geographic, solar zenith angle, local time, and seasonal dependencies of auroral occurrence. Higher occurrence of aurora is observed in regions of open magnetic topology, where crustal magnetic fields are either very weak or both strong and vertical. Aurora occurs more frequently closer to the terminator and is more likely on the dusk side than on the dawn side of the night hemisphere. A pronounced auroral feature appears close to midnight local times in the southern hemisphere, consistent with the spot of energetic electron fluxes previously identified in the Mars Global Surveyor data. This auroral spot is more frequent after midnight than before. Additionally, some regions on Mars are “aurora voids” where essentially no aurora occurs. Aurora exhibits a seasonal dependence, with a major enhancement near perihelion. Non–crustal field aurora additionally shows a secondary enhancement near L_s 30°. This seasonal variability is a combination of the variability in ionospheric photoelectrons and thermospheric atomic oxygen abundance. Auroral occurrence also shows an increase with the rise of Solar Cycle 25. The brightest auroral pixels are observed during space weather events such as Coronal Mass Ejections and Stream Interaction Regions. These observations not only shed light on where and when Martian aurora occurs, but also add to our understanding of Mars' magnetic environment and its interaction with the heliosphere.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008336","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141435601","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":"The Role of Ice and Latitude-Dependent Mantling on Boulder Distributions Across the Martian Northern Lowlands","authors":"A. L. Cohen-Zada,&nbsp;D. R. Hood,&nbsp;R. C. Ewing,&nbsp;S. Karunatillake","doi":"10.1029/2024JE008387","DOIUrl":"https://doi.org/10.1029/2024JE008387","url":null,"abstract":"<p>Boulders are ubiquitous on rocky planets and provide valuable information about planetary processes. The abundance, size, and distribution of boulders offer insights into the primary processes that form them and the secondary processes that modify their position and size. However, the roles of varying environmental processes, including cryospheric processes, are poorly known. In this study, we analyze over 20 million boulders in the northern lowlands of Mars (50–70°N) to evaluate their distribution and identify environmental factors that might influence their clustering. We used spatial statistics to quantify the degree of boulder clustering across the northern plains. We found two latitudinal trends: overall decreasing clustering with increasing latitude (50–70°N) and a sub-trend of increased clustering at higher latitudes (65–70°N). Our findings suggest that boulder distribution patterns are linked to the latitude-dependent mantle (LDM) and subsurface ice. Boulders exhibit higher spatial clustering at higher latitudes, where the ice is thick and continuously present, and the LDM is more pristine. Lower clustering occurs at lower latitudes or regions where the ice loss is likely during interglacial periods, and the LDM degrades, exposing more boulders of varying sizes. We also discovered an anomalous region where boulder clustering is nearly random, located on the edge of the Alba Mons Patera. This area displays distinct geophysical characteristics compared to the rest of the lowlands. Although these characteristics do not indicate a specific process for the variation of boulder distribution in this study, the data suggest a coupling between cryospheric processes and boulder evolution, warranting further research.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008387","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141424990","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}