Journal of Geophysical Research: Planets最新文献

{"title":"The Isotopic Variation of K and Fe in Apollo 17 Double Drive Tube 73001/2 and Implications for Regolith History and Space Weathering","authors":"M. Broussard,&nbsp;M. Neuman,&nbsp;B. L. Jolliff,&nbsp;P. Koefoed,&nbsp;R. L. Korotev,&nbsp;R. V. Morris,&nbsp;K. C. Welten,&nbsp;K. Wang","doi":"10.1029/2024JE008371","DOIUrl":"https://doi.org/10.1029/2024JE008371","url":null,"abstract":"<p>Space weathering alters the surface materials of airless planetary bodies; however, the effects on moderately volatile elements in the lunar regolith are not well constrained. For the first time, we provide depth profiles for stable K and Fe isotopes in a continuous lunar regolith core, Apollo 17 double drive tube 73001/2. The top of the core is enriched in heavy K isotopes (δ⁴¹K = 3.48 ± 0.05‰) with a significant trend toward lighter K isotopes to a depth of 7 cm; while the lower 44 cm has only slight variation with an average δ⁴¹K value of 0.15 ± 0.05‰. Iron, which is more refractory, shows only minor variation; the δ⁵⁶Fe value at the top of the core is 0.16 ± 0.02‰ while the average bottom 44 cm is 0.11 ± 0.03‰. The isotopic fractionation in the top 7 cm of the core, especially the K isotopes, correlates with soil maturity as measured by ferromagnetic resonance. Kinetic fractionation from volatilization by micrometeoroid impacts is modeled in the double drive tube 73001/2 using Rayleigh fractionation and can explain the observed K and Fe isotopic fractionation. Effects from cosmogenic ⁴¹K (from decay of ⁴¹Ca) were calculated and found to be negligible in 73001/2. In future sample return missions, researchers can use heavy K isotope signatures as tracers of space weathering effects.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008371","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861448","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":"Low Rock Mass Fraction Within Trans-Neptunian Objects Inferred From the Spin–Orbit Evolution of Orcus–Vanth and Salacia–Actaea","authors":"S. Arakawa,&nbsp;S. Kamata,&nbsp;H. Genda","doi":"10.1029/2024JE008923","DOIUrl":"https://doi.org/10.1029/2024JE008923","url":null,"abstract":"<p>Satellites play a crucial role in understanding the formation and evolution of trans-Neptunian objects (TNOs). The spin–orbit evolution of satellite systems depends on their thermal histories, allowing us to constrain the rock mass fraction within TNOs based on their current spin–orbit states. In this study, we perform coupled thermal–orbital evolution calculations for two satellite systems around undifferentiated TNOs: Orcus–Vanth and Salacia–Actaea. Our results demonstrate that the current spin–orbit states of these systems are consistent with a rock mass fraction of approximately 20%–30%. Additionally, we estimate the organic mass fraction within the TNOs and find that it is comparable to the rock mass fraction. These findings suggest that the chemical composition of TNOs closely resembles that of comets.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861516","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":"Landscape Evolution Models of Incision on Mars: Implications for the Ancient Climate","authors":"Amanda V. Steckel,&nbsp;Gregory E. Tucker,&nbsp;Matthew Rossi,&nbsp;Brian Hynek","doi":"10.1029/2024JE008637","DOIUrl":"https://doi.org/10.1029/2024JE008637","url":null,"abstract":"<p>Large dendritic valley networks observed on Mars present a paleoclimate paradox. Geologic observations of Noachian units on Mars reveal a global extent of valley networks, which are believed to have been formed through incisions made by flowing water. However, most climate models predict global surface temperatures too far below the freezing point of water to support an active hydrological system. Conflicting observations and models have led to disparate theories for the climate of early Mars. In this work, we surveyed a large region of the cratered southern highlands to identify the location, elevation, and distribution of observed valley heads. These valley head locations were compared to landscape evolution simulations in which the spatial distribution of runoff was varied. The measured valley head distributions were compared to predictions from landscape evolution models for two end-member hypotheses: (a) a warm wet climate that supported spatially distributed precipitation, and (b) surface runoff from ice cap margins, as envisioned by the Late Noachian Icy Highland model (LNIH). The observed elevation distribution in valley heads is consistent with the prediction of precipitation-fed models, and inconsistent with models in which runoff derives exclusively from a single line-source of high-elevation ice-melt. The results support the view that it is unlikely for ice caps to be the sole source of water and are consistent with the hypothesis that precipitation significantly contributed to valley network formation on ancient Mars.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143853071","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":"Shock-Induced Devolatilization of Phlogopite, an Archetypical Phyllosilicate","authors":"X. Zhu,&nbsp;Y. Ye,&nbsp;R. Caracas","doi":"10.1029/2024JE008839","DOIUrl":"https://doi.org/10.1029/2024JE008839","url":null,"abstract":"<p>The formation and evolution of rocky planets such as the Earth are marked by the heavy bombardments that dominated the first parts of the accretions. The outcomes of the large and giant impacts depend on the critical points and liquid-vapor equilibria of the constituent materials. Several determinations of the positions of the critical points have been conducted in the last few years, but they have mainly focused on systems devoid of volatiles. Here, we study, for the first time, a volatile-rich ubiquitous model mineral, phlogopite. For this, we employ ab initio molecular dynamics simulations. Its critical point is constrained in the 0.40–0.68 g/cm³ density range and 5,000–5,500 K temperature range. This shows that adding volatiles decreases the critical temperature of silicates while having a smaller effect on the critical density. The vapor phase that forms under cooling from the supercritical state is dominated by hydrogen, present in the form of H₂O, H, OH, with oxygen and various F-bearing phases coming next. Our simulations show that up to 93% of the total hydrogen is retained in the silicate melt. Our results suggest that early magma oceans must have been hydrated. In particular for the Moon's history, even if catastrophic dehydrogenation occurred during the cooling of the lunar magma ocean, the amount of water incorporated during its formation could have been sufficient to explain the amounts of water found today in the last lunar samples.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143853072","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":"Thermophysical States of MgSiO3 Liquid up to Terapascal Pressures: Implications for Magma Oceans in Super-Earths and Sub-Neptunes","authors":"Haiyang Luo,&nbsp;Jie Deng","doi":"10.1029/2024JE008678","DOIUrl":"https://doi.org/10.1029/2024JE008678","url":null,"abstract":"<p>Thermophysical properties of silicate liquids under extreme conditions are critical for understanding the accretion and evolution of super-Earths and sub-Neptunes. The thermal equation of state and viscosity of silicate liquids determine the adiabatic profiles and dynamics of magma oceans. However, these properties are challenging to constrain at elevated pressures in experiments. Here, we perform ab initio molecular dynamics simulations of MgSiO₃ liquid across a wide range of pressures (0–1,200 GPa) and temperatures (2200–14000 K) and analyze its structure, the Grüneisen parameter, and viscosity. Our results reveal the clear temperature and pressure dependence of the Grüneisen parameter, which varies synchronously with the O-O coordination number. The Grüneisen parameter shifts from positive to negative temperature dependence between ∼20 and 70 GPa, corresponding to a peak in the O-O coordination number and SiO₅ abundance. Initially, the Grüneisen parameter increases with pressure and then decreases, showing limited temperature dependence above ∼300 GPa, where its behavior resembles that of solids. Furthermore, we determine the adiabat and viscosity profiles of magma oceans in super-Earths and sub-Neptunes. The results suggest that the mantles of super-Earths and sub-Neptunes may solidify either from the bottom up or at pressures of ∼120–150 GPa, depending on the curvature of the mantle melting line. The low viscosity of magma oceans likely enhances convective currents and facilitate efficient differentiation. These thermophysical properties, now quantified up to terapascal pressures, enable updates to the mass-radius relation of magma ocean exoplanets, showing notable differences compared to their solid counterparts.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008678","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856876","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":"Multispectral Properties of Rocks in Marker Band Valley and Evidence for an Alteration Unit Below the Amapari Marker Band at Gale Crater, Mars","authors":"W. H. Farrand,&nbsp;A. M. Eng,&nbsp;A. R. Trussell,&nbsp;J. R. Johnson,&nbsp;J. F. Bell III,&nbsp;S. G. Banham,&nbsp;A. L. Roberts,&nbsp;L. M. Thompson,&nbsp;E. B. Rampe,&nbsp;C. J. Hardgrove,&nbsp;C. M. Fedo,&nbsp;A. A. Fraeman,&nbsp;C. M. Weitz","doi":"10.1029/2024JE008645","DOIUrl":"https://doi.org/10.1029/2024JE008645","url":null,"abstract":"<p>The Mars Science Laboratory rover, Curiosity, has been examining strata from a period of Martian history where extensive clay mineral formation transitioned to sulfate mineral formation. This mineralogic change corresponds to a change from a wetter to a more arid climate. Among the tools used by Curiosity to study the rocks that recorded this transition is the multispectral capability of its Mast Camera (Mastcam). The Mastcam filter wheel, in combination with its Bayer Pattern filter focal plane array has provided multispectral scenes recorded in 12 spectral bands over the 445–1,013 nm spectral range. Here, Mastcam multispectral results from the rover's exploration of predominantly sulfate-bearing strata that bracket a distinct dark-toned resistant stratigraphic marker unit, now referred to as the Amapari Marker Band (AMB), are presented in association with supporting information from some of Curiosity's other instruments. Using an agglomerative hierarchical clustering approach, six spectral classes were derived. These classes included three stratigraphic classes plus a class indicating more intense diagenetic alteration and classes of dark-toned float rocks and a set of Fe-Ni meteorites. These spectral classes were compared to the spectra of analogous terrestrial materials. Among the observations, a distinct tonal and color unit was observed directly below the Amapari Marker Band. Several lines of evidence suggest this narrow interval is an alteration horizon. The alteration could have resulted from diagenesis, exposure as a weathering surface, or from introduction of water associated with the deposition of the lower AMB.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008645","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143849041","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":"A Search for the Near-Surface Particulate Layer Using Venera 13 In Situ Spectroscopic Observations","authors":"Shubham V. Kulkarni,&nbsp;Patrick G. J. Irwin,&nbsp;Colin F. Wilson,&nbsp;Nikolai I. Ignatiev","doi":"10.1029/2024JE008728","DOIUrl":"https://doi.org/10.1029/2024JE008728","url":null,"abstract":"<p>Whether or not there is a particulate layer in the lowest 10 km of the Venusian atmosphere is still an open question. Some of the past in situ experiments showed the presence of a detached particulate layer, and a few suggested the existence of finely dispersed aerosols, while other instruments supported the idea of no particulate matter in the deep atmosphere. In this work, we investigate the presence of a near-surface particulate layer (NSPL) using in situ data from the Venera 13 mission. While the original spectrophotometric data from Venera 13 were lost, we have reconstructed a part of this data by digitizing the old graphic material and selected the eight most reliable Venera 13 downward radiance profiles from 0.48 to 0.8 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>μ</mi>\u0000 </mrow>\u0000 <annotation> ${upmu }$</annotation>\u0000 </semantics></math>m for our retrievals. The retrievals suggest the existence of the particulate layer with a peak in the altitude range of 3.5–5 km. They further indicate a log-normal particle size distribution with a mean radius between 0.6 and 0.85 <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mi>μ</mi>\u0000 </mrow>\u0000 <annotation> ${upmu }$</annotation>\u0000 </semantics></math>m. The retrievals constrain the real refractive index of the particles to lie around the range of 1.4–1.6, with the imaginary refractive index of a magnitude of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msup>\u0000 <mn>10</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>3</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${10}^{-3}$</annotation>\u0000 </semantics></math>. Based on refractive index retrievals, uplifted basalt particles or volcanic ash could be responsible for near-surface particulates. In comparison, volatile condensates appear less likely to be behind the formation of NSPL.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008728","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143849119","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":"Rapid Hydrofracture of Icy Moon Shells: Insights From Glaciology","authors":"Robert Law","doi":"10.1029/2024JE008403","DOIUrl":"https://doi.org/10.1029/2024JE008403","url":null,"abstract":"<p>Europa's surface exhibits many regions of complex topography termed “chaos terrains.” One set of hypotheses for chaos terrain formation requires upward migration of liquid water from perched water bodies within the icy shell formed by convection and tidal heating. However, consideration of the behavior of terrestrial ice sheets suggests the upwards movement of water from englacial water bodies is uncommon. Instead, rapid downwards hydrofracture from supraglacial lakes—unbounded given a sufficient volume of water—can occur in relatively low tensile stress states given a sufficiently deep initial fracture due to the negative relative buoyancy of water. I suggest that downwards, not upwards, fracture may be more reasonable for perched water bodies but show that full hydrofracture is unlikely if the perched water body is located beneath a mechanically strong icy lid. However, full hydrofracture is possible in the event of lid break up over a perched water body and likely in the event of a meteor impact that generates sufficient meltwater and a tensile shock. This provides a possible mechanism for the transfer of biologically important nutrients to the subsurface ocean and the formation of chaos terrains.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143840607","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":"The Atmospheric Response to an Unusual Early-Year Martian Dust Storm","authors":"Cong Sun,&nbsp;Chengyun Yang,&nbsp;Tao Li,&nbsp;Dexin Lai,&nbsp;Xin Fang","doi":"10.1029/2024JE008694","DOIUrl":"https://doi.org/10.1029/2024JE008694","url":null,"abstract":"<p>A regional dust storm was observed in the northern spring of Martian Year 35, characterized by a relatively cold and clear atmosphere. Satellite observations and general circulation model simulations show that the atmospheric temperature response to this early regional dust storm is significant, both in the dust lifting region and in remote areas. Atmospheric heating in the dust-lifting region was primarily driven by shortwave radiative heating of dust particles. Anomalous cooling in the northern mesosphere and heating responses in the southern troposphere were associated with dust-modulated gravity waves and planetary waves, respectively. Inhomogeneous heating from dust distribution during the storm generated anomalous atmospheric waves, significantly enhancing southward meridional circulation and lifting water vapor in the lower tropical troposphere. This dust storm substantially increased meridional water transport from the Northern Hemisphere to the Southern Hemisphere, with pronounced longitudinal asymmetry underscoring the influence of tropical topographic features on water vapor transport.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143830982","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":"Questioning the Reliability of Methane Detections on Mars by the Curiosity Rover","authors":"Sébastien Viscardy,&nbsp;David C. Catling,&nbsp;Kevin Zahnle","doi":"10.1029/2024JE008441","DOIUrl":"https://doi.org/10.1029/2024JE008441","url":null,"abstract":"<p>Over the past decade, the Tunable Laser Spectrometer (TLS) on NASA's Curiosity rover has reported several detections of methane on Mars, attracting attention due to the potential astrobiological implications of its presence. Here, we re-analyze published TLS data, identifying issues in data robustness and reduction. We find that the TLS foreoptics chamber typically contained methane abundances that were 3–4 orders of magnitude greater than those reported in the sample cell, alongside unexpected and rapidly varying pressure changes inside the instrument. Using information from unreported experiments where methane diffusion into the cell was observed, we estimate a gas transport coefficient and develop a model to simulate gas exchanges between the two compartments in typical experiments, investigating the implications for methane measurements. We find that tiny leaks (&lt;0.1% of foreoptics methane) would suffice to explain the reported atmospheric methane measurements—leaks that are otherwise undetectable from housekeeping data. Furthermore, in an analysis of five experiments where more complete data are available, we find that the TLS retrieval method—which averages discrepant methane levels from the three lines of the R3 triplet as if the three lines were independent, rather than fitting the spectrum to the distinctive pattern of the triplet itself—likely underestimates uncertainties. The probability that three methane levels from individual triplet lines are disparate in all five experiments is typically ∼10⁻³, suggesting the presence of systematic errors that are unaccounted for in previously reported methane levels. Finally, we propose a constructive two-step experiment to further investigate our findings.</p>","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":"130 4","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008441","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143826789","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}