Journal of Geophysical Research: Planets最新文献_第7页

The Dynamics of CO2-Driven Granular Flows in Gullies on Mars 火星沟壑中二氧化碳驱动的颗粒流动力学

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-06-15 DOI: 10.1029/2024JE008319

Lonneke Roelofs, Susan J. Conway, Bas van Dam, Arjan van Eijk, Jonathan P. Merrison, Jens Jacob Iversen, Matthew Sylvest, Manish R. Patel, Henk Markies, Marcel van Maarseveen, Jim McElwaine, Maarten G. Kleinhans, Tjalling de Haas

{"title":"The Dynamics of CO2-Driven Granular Flows in Gullies on Mars","authors":"Lonneke Roelofs, Susan J. Conway, Bas van Dam, Arjan van Eijk, Jonathan P. Merrison, Jens Jacob Iversen, Matthew Sylvest, Manish R. Patel, Henk Markies, Marcel van Maarseveen, Jim McElwaine, Maarten G. Kleinhans, Tjalling de Haas","doi":"10.1029/2024JE008319","DOIUrl":"https://doi.org/10.1029/2024JE008319","url":null,"abstract":"Martian gullies are landforms consisting of an erosional alcove, a channel, and a depositional apron. A significant proportion of Martian gullies at the mid-latitudes is active today. The seasonal sublimation of CO2 ice has been suggested as a driver behind present-day gully activity. However, due to a lack of in situ observations, the actual processes causing the observed changes remain unresolved. Here, we present results from flume experiments in environmental chambers in which we created CO2-driven granular flows under Martian atmospheric conditions. Our experiments show that under Martian atmospheric pressure, large amounts of granular material can be fluidized by the sublimation of small quantities of CO2 ice in the granular mixture (only 0.5% of the volume fraction of the flow) under slope angles as low as 10°. Dimensionless scaling of the CO2-driven granular flows shows that they are dynamically similar to terrestrial two-phase granular flows, that is, debris flows and pyroclastic flows. The similarity in flow dynamics explains the similarity in deposit morphology with levees and lobes, supporting the hypothesis that CO2-driven granular flows on Mars are not merely modifying older landforms, but they are actively forming them. This has far-reaching implications for the processes thought to have formed these gullies over time. For other planetary bodies in our solar system, our experimental results suggest that the existence of gully like landforms is not necessarily evidence for flowing liquids but that they could also be formed or modified by sublimation-driven flow processes.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008319","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141329359","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}

引用次数: 0

Revealing the Local Time Structure of the Alfvén Radius in Jupiter's Magnetosphere Through High-Resolution Simulations 通过高分辨率模拟揭示木星磁层中阿尔芬半径的局部时间结构

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-06-15 DOI: 10.1029/2024JE008368

Yan Xu, Licia Ray, Zhonghua Yao, Binzheng Zhang, Bertrand Bonfond, Sarah Badman, Denis Grodent, Enhao Feng, Tianshu Qin, Yong Wei

{"title":"Revealing the Local Time Structure of the Alfvén Radius in Jupiter's Magnetosphere Through High-Resolution Simulations","authors":"Yan Xu, Licia Ray, Zhonghua Yao, Binzheng Zhang, Bertrand Bonfond, Sarah Badman, Denis Grodent, Enhao Feng, Tianshu Qin, Yong Wei","doi":"10.1029/2024JE008368","DOIUrl":"https://doi.org/10.1029/2024JE008368","url":null,"abstract":"In the context of planetary magnetospheres, the Alfvén radius plays a critical role as the demarcation line where the planet's magnetosphere and ionosphere effectively decouple. This boundary is pivotal in understanding the complex interactions between planetary magnetic fields and space plasma environments. This study presents a dynamic analysis of the Alfvén radius within Jupiter's magnetosphere using high-resolution simulations to capture its temporal variability. Our simulations reveal that the Alfvén radius presents a dynamic behavior, which is strongly modulated by planetary rotation. However, when averaged over one Jovian rotation period, the location of the Alfvén radius displays striking similarities to that described by the statistical models proposed by Jenkins et al. (2024, 10.17635/lancaster/researchdata/661). Specifically, our averaged results highlight a prominent outward bulge in the radius location toward ∼03 local time with a notable absence of the radius between the noon and dusk sectors. The absence of the Alfvén radius suggests the higher Alfvén velocities in the noon-to-dusk sector associated with strong magnetic fields. These results suggest that while short-term dynamics are present, the average position of the Alfvén radius over a rotation period roughly remains consistent with previous steady-state models, providing an enhanced understanding of the long-term behavior exhibited by the magnetospheric plasma environment in Jupiter's magnetosphere. Importantly, the dynamic location of the Alfvén radius and the observed asymmetry after averaging over one rotation period could demonstrate a significant correlation with the complex evolution of the auroral enhancement.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008368","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141329360","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}

引用次数: 0

From Disorder to Order: Inheritance of Magnetic Remanence in Tetrataenite-Bearing Meteorites From Multi-Phase Micromagnetic Modeling 从无序到有序：从多相微磁建模看含四钛铁矿陨石的磁剩磁继承性

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-06-14 DOI: 10.1029/2023JE008268

José A. P. M. Devienne, Thomas A. Berndt, Wyn Williams, Shichu Chen

{"title":"From Disorder to Order: Inheritance of Magnetic Remanence in Tetrataenite-Bearing Meteorites From Multi-Phase Micromagnetic Modeling","authors":"José A. P. M. Devienne, Thomas A. Berndt, Wyn Williams, Shichu Chen","doi":"10.1029/2023JE008268","DOIUrl":"https://doi.org/10.1029/2023JE008268","url":null,"abstract":"An increasing amount of evidence suggests that the tetrataenite-bearing cloudy zones (CZ) in iron and stony-iron meteorites can preserve magnetic records of ancient magnetic activity of their parent bodies over solar system timescales. Tetrataenite islands in the CZ are nanometer-sized (<200 nm) crystals that usually form through ordering from precursor taenite islands upon extremely slow cooling through 320°C. Recent micromagnetic models have shown that such precursor taenite islands form highly thermally stable single-domain (SD) or single-vortex states (SV). In this work we employ a 3D finite element multi-phase micromagnetic modeling to show that tetrataenite inherits the magnetic remanence of taenite precursor when it forms over underlying SD states. When taenite forms SV states, however, tetrataenite resets the precursor magnetization and records a new remanence through chemical ordering at 320°C. We further assess the thermal stability of tetrataenite islands. We show that in cases where tetrataenite inherits the domain states of its precursor taenite, the origin of the remanence can be up to ∼105 years older than previously thought in fast-cooled meteorites, and ∼1–≳6 Myr in slowly cooled meteorites. It indicates, therefore, that different regions across slowly cooled CZ record distinct stages of planetary formation.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141326468","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}

引用次数: 0

Tidal Forcing in Icy-Satellite Oceans Drives Mean Circulation and Ice-Shell Torques 冰卫星洋的潮汐作用力驱动平均环流和冰壳转矩

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-06-07 DOI: 10.1029/2024JE008408

Hamish C. F. C. Hay, Ian Hewitt, Richard F. Katz

{"title":"Tidal Forcing in Icy-Satellite Oceans Drives Mean Circulation and Ice-Shell Torques","authors":"Hamish C. F. C. Hay, Ian Hewitt, Richard F. Katz","doi":"10.1029/2024JE008408","DOIUrl":"https://doi.org/10.1029/2024JE008408","url":null,"abstract":"Tidal forces generate time-varying currents in bodies with fluid layers, such as the icy ocean moons of the outer solar system. The expectation has been that tidal currents are periodic—they average to zero over a forcing period—so that they are not associated with a mean flow. This expectation arises from the assumption of linearity. Here, we relax this assumption and develop a theory that predicts the emergence of mean currents driven by any periodic forcing. The theory, derived in the context of a global, uniform, shallow ocean, constitutes a set of mean flow equations forced by non-linear eddy fluctuations. The latter are the canonical, periodic tidal currents predicted by the Laplace Tidal equations. We show that the degree-2 tide-raising potential due to obliquity and/or orbital eccentricity can drive time-averaged currents with zonal wavenumbers from 0 to 4. The most prominent of these is a retrograde zonal jet driven by the obliquity-forcing potential. Assuming Cassini state obliquities, this jet has speeds ranging from 0.01 to 1 mm s−1, which can exert torques up to roughly 1015 N m at the ice–ocean interfaces of Europa, Callisto, Titan, and Triton. Depending on the viscosity of the ice shell, these torques could drive ice shell drift rates of tens to potentially hundreds of meters a year. Thinner or stably stratified global oceans can experience much faster mean currents.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JE008408","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141292610","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}

引用次数: 0

Lithologies and Chronologic Opportunities of Materials to Be Returned From the Artemis Exploration Zone 将从阿耳特弥斯勘探区返回的材料的岩性和年代机会

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-06-03 DOI: 10.1029/2023JE008275

Ruby V. Patterson, Thomas J. Lapen, David A. Kring, Myriam Lemelin, McKayla L. Meier

{"title":"Lithologies and Chronologic Opportunities of Materials to Be Returned From the Artemis Exploration Zone","authors":"Ruby V. Patterson, Thomas J. Lapen, David A. Kring, Myriam Lemelin, McKayla L. Meier","doi":"10.1029/2023JE008275","DOIUrl":"https://doi.org/10.1029/2023JE008275","url":null,"abstract":"The Artemis exploration zone is a geologically complex region likely to host some of the oldest and as-yet-unstudied materials on the Moon. We review six potential Artemis landing sites (001, 004, 007, 011, 102, and 105) within candidate Artemis III landing regions ”Connecting Ridge,“ “Peak Near Shackleton,” “Leibnitz Beta Plateau,” “de Gerlache Rim,” and “de Gerlache Rim 2.” Kaguya Spectral Profiler mineral data were used to determine the average lithological composition at each landing site. Potentially accessible geologic materials, their ages and significance, and appropriate application of radiometric chronometers are discussed in reference to return samples from each potential landing site. Chronological analyses of return samples from the Artemis exploration zone will enable the anchoring of the lunar impact flux curve, determine the absolute timing of pivotal events in lunar geologic history, and reveal the geological diversity of the differentiated lunar body.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008275","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141245479","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}

引用次数: 0

On the Formation Mechanism of Martian Dayside Ionospheric Plasma Depletion Events 论火星日侧电离层等离子体耗竭事件的形成机制

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-05-30 DOI: 10.1029/2023JE008227

Praveen Basuvaraj, František Němec, C. M. Fowler, Leonardo H. Regoli, Zdeněk Němeček, Jana Šafránková

引用次数: 0

Possibility of Lunar Crustal Magmatism Producing Strong Crustal Magnetism 月壳岩浆活动产生强地壳磁性的可能性

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-05-20 DOI: 10.1029/2023JE008179

Y. Liang, S. M. Tikoo, M. J. Krawczynski

{"title":"Possibility of Lunar Crustal Magmatism Producing Strong Crustal Magnetism","authors":"Y. Liang, S. M. Tikoo, M. J. Krawczynski","doi":"10.1029/2023JE008179","DOIUrl":"https://doi.org/10.1029/2023JE008179","url":null,"abstract":"The Moon generated a long-lived core dynamo magnetic field, with intensities at least episodically reaching ∼10–100 μT during the period prior to ∼3.56 Ga. While magnetic anomalies observed within impact basins are likely attributable to the presence of impactor-added metal, other anomalies such as those associated with lunar swirls are not as conclusively linked to exogenic materials. This has led to the hypothesis that some anomalies may be related to magmatic features such as dikes, sills, and laccoliths. However, basalts returned from the Apollo missions are magnetized too weakly to produce the required magnetization intensities (>0.5 A/m). Here, we test the hypothesis that subsolidus reduction of ilmenite within or adjacent to slowly cooled mafic intrusive bodies could locally enhance metallic FeNi contents within the lunar crust. We find that reduction within hypabyssal dikes with high-Ti or low-Ti mare basalt compositions can produce sufficient FeNi grains to carry the minimum >0.5 A/m magnetization intensity inferred for swirls, especially if ambient fields are >10 μT or if fine-grained Fe-Ni metals in the pseudo-single domain grain size range are formed. Therefore, there exists a possibility that certain magnetic anomalies exhibiting various shapes such as linear, swarms, and elliptical patterns may be magmatic in origin. Our study highlights that the domain state of the magnetic carriers is an under-appreciated factor in controlling a rock's magnetization intensity. The results of this study will help guide interpretations of lunar crustal field data acquired by future rovers that will traverse lunar magnetic anomalies.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141073739","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}

引用次数: 0

Planetary Paleomagnetic Intensity Recording Fidelity Test Using a Synthetic Lava 利用合成熔岩进行行星古地磁强度记录保真度测试

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-05-19 DOI: 10.1029/2023JE008055

Chen Wen, Huapei Wang, Yu-Min Chou, Chun-Chieh Wang, Xiaowei Chen, Fei Han, Junxiang Miao, Yiming Ma, Jiabo Liu, Jeffrey A. Karson

{"title":"Planetary Paleomagnetic Intensity Recording Fidelity Test Using a Synthetic Lava","authors":"Chen Wen, Huapei Wang, Yu-Min Chou, Chun-Chieh Wang, Xiaowei Chen, Fei Han, Junxiang Miao, Yiming Ma, Jiabo Liu, Jeffrey A. Karson","doi":"10.1029/2023JE008055","DOIUrl":"https://doi.org/10.1029/2023JE008055","url":null,"abstract":"Meteorite paleomagnetism is fundamental to understanding planetary dynamo processes and the evolution of the early Solar System. However, due to the extraterrestrial and ancient origins of meteorites, their paleomagnetic recording fidelity remains uncertain, which can be tested from a planetary sample formed in a known field. On Earth, historic lavas are used to examine paleomagnetic recording fidelity through the Thellier-series experiment and other paleointensity methods, which can produce paleointensity estimates to test against the known field strength. But natural terrestrial rocks have different magnetic mineralogy from planetary samples, so they cannot faithfully infer the recording fidelity of meteorites. Here, we used an iron-particle-bearing sample from the Syracuse University Lava Project (SULP), which is analogous to the lunar basalts and howardite-eucrite-diogenite meteorites and forms in the present-day Earth's field, to investigate the recording fidelity of these meteorites. No remanence has been identified in the high coercivity range with alternating field (AF) demagnetization due to the sample's low coercivity and AF noise, which produces underestimated paleointensities. Two accurate thermal paleointensities indicate that we may acquire accurate paleointensities from non-ideal multidomain (MD) iron grains with the Thellier-Coe and RESET methods, but the success rate is low due to the MD effect and thermal alteration in the experiments. Our results imply that MD iron-bearing meteorites have the potential to provide accurate paleointensities that can be used to constrain planetary processes.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141069063","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}

引用次数: 0

A Scaling Relation for Core Heating by Giant Impacts and Implications for Dynamo Onset 巨型撞击对地核加热的比例关系及其对动力机启动的影响

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-05-19 DOI: 10.1029/2023JE008163

You Zhou, Peter E. Driscoll, Mingming Zhang, Christian Reinhardt, Thomas Meier

{"title":"A Scaling Relation for Core Heating by Giant Impacts and Implications for Dynamo Onset","authors":"You Zhou, Peter E. Driscoll, Mingming Zhang, Christian Reinhardt, Thomas Meier","doi":"10.1029/2023JE008163","DOIUrl":"https://doi.org/10.1029/2023JE008163","url":null,"abstract":"Accretional heating of Earth's interior during formation is pivotal to its subsequent thermal and chemical evolution. In particular, impact heating of Earth's core is expected, but its amplitude and radial distribution within the core is unknown and could influence the onset of the geodynamo. The uncertainty is due, in part, to the lack of constraints on the temperature of the interior following formation due to the difficulty of preserving a record of such a high energy environment, and the assertion that super-heating during formation would be rapidly lost through magma ocean cooling. Here we systematically investigate core heating due to giant impacts using a Smoothed Particle Hydrodynamics (SPH) code with simulations spanning a range of impact angles, velocities, and masses. From these simulations we derive a scaling relation for core heating that depends on the impact parameters and predicts the radial core temperature profile following the impact. Our findings show that a significant amount of heat is deposited into the core, with a canonical impact scenario resulting in an average core temperature increase of about 3000 K, approximately 500 K higher than that of the overlying mantle. In this case the heat distribution within the core produces a strong thermal stratification. We use a parameterized cooling model to estimate that the core could have cooled to an adiabatic state ∼290 Myr after a canonical impact, which is consistent with the observed time span between the age of the Moon and evidence for an active geodynamo.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141069064","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}

引用次数: 0

Lunar Farside South Pole-Aitken Basin Interior: Evidence for More Extensive Central Cryptomaria in the South Pole-Aitken Compositional Anomaly (SPACA) 月球远侧南极-艾特肯盆地内部：南极-艾特肯成分异常（SPACA）中更广泛的中央隐花植物的证据

IF 4.8 1区地球科学

Journal of Geophysical Research: Planets Pub Date : 2024-05-17 DOI: 10.1029/2023JE008176

Xing Wang, James W. Head, Yuan Chen, Feiyue Zhao, Mikhail A. Kreslavsky, Lionel Wilson, Yuqi Qian, Jianjun Liu, Chunlai Li

{"title":"Lunar Farside South Pole-Aitken Basin Interior: Evidence for More Extensive Central Cryptomaria in the South Pole-Aitken Compositional Anomaly (SPACA)","authors":"Xing Wang, James W. Head, Yuan Chen, Feiyue Zhao, Mikhail A. Kreslavsky, Lionel Wilson, Yuqi Qian, Jianjun Liu, Chunlai Li","doi":"10.1029/2023JE008176","DOIUrl":"https://doi.org/10.1029/2023JE008176","url":null,"abstract":"In the central area of the South Pole-Aitken (SPA) basin, an intermediate albedo, mafic compositional anomaly (SPA Compositional Anomaly, SPACA) has been documented by previous studies, but its origin remains uncertain. We conducted an investigation of stratigraphic units defined based on morphology and composition and their relative ages, and placed these in the context of basin topography and the observed sequence of geological events, all helping to distinguish between SPACA origins from: (a) SPA impact melt, (b) volcanism induced by the SPA event and (c) lunar cryptomaria. We conclude that SPACA represents extensive traditional cryptomare deposits overlying the SPA impact melt. We interpret the basin center to be filled with cryptomare deposits at least one km thick (>1 × 105 km3 in volume) with ages not younger than Early Imbrian. We attribute the relatively high albedo of SPACA to lateral mixing of ejecta from nearby highlands craters and basins, and conclude that the cryptomaria basalts are likely to be very similar to basalts on the nearside. Our findings imply a 0.5%–1.8% increase in the total volume of global lunar mare and cryptomare deposits. These results show that mare volcanism was common only in areas of thinnest crust on the lunar farside, a factor important in understanding lunar nearside-farside asymmetries. Despite this significant increase in total cryptomare volume in the SPA basin center, SPA remains underfilled relative to nearside mascon basins. Return of mare basalts from the SPA region by Chang’E-6 will help determine potential mantle source region differences and petrogenetic pathways.","PeriodicalId":16101,"journal":{"name":"Journal of Geophysical Research: Planets","volume":null,"pages":null},"PeriodicalIF":4.8,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JE008176","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140952712","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}

引用次数: 0