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Yu S, Xiao X, Gong S, Tosi N, Huang J, Breuer D, Xiao L, Ni D. Long-lived lunar volcanism sustained by precession-driven core-mantle friction. Natl Sci Rev 2024; 11:nwad276. [PMID: 38213526 PMCID: PMC10776352 DOI: 10.1093/nsr/nwad276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 10/11/2023] [Accepted: 10/29/2023] [Indexed: 01/13/2024] Open
Abstract
Core-mantle friction induced by the precession of the Moon's spin axis is a strong heat source in the deep lunar mantle during the early phase of a satellite's evolution, but its influence on the long-term thermal evolution still remains poorly explored. Using a one-dimensional thermal evolution model, we show that core-mantle friction can sustain global-scale partial melting in the upper lunar mantle until ∼3.1 Ga, thus accounting for the intense volcanic activity on the Moon before ∼3.0 Ga. Besides, core-mantle friction tends to suppress the secular cooling of the lunar core and is unlikely to be an energy source for the long-lived lunar core dynamo. Our model also favours the transition of the Cassini state before the end of the lunar magma ocean phase (∼4.2 Ga), which implies a decreasing lunar obliquity over time after the solidification of the lunar magma ocean. Such a trend of lunar obliquity evolution may allow volcanically released water to be buried in the lunar regolith of the polar regions. As a consequence, local water ice could be more abundant than previously thought when considering only its accumulation caused by solar wind and comet spreading.
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Affiliation(s)
- Shuoran Yu
- State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau 999078, China
| | - Xiao Xiao
- Planetary Science Institute, State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Shengxia Gong
- CAS Key Laboratory of Planetary Sciences, Shanghai Astronomical Observatory, Shanghai 200030, China
| | - Nicola Tosi
- Institute of Planetary Research, German Aerospace Centre (DLR), Berlin 12489, Germany
| | - Jun Huang
- Planetary Science Institute, State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Doris Breuer
- Institute of Planetary Research, German Aerospace Centre (DLR), Berlin 12489, Germany
| | - Long Xiao
- Planetary Science Institute, State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
| | - Dongdong Ni
- State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau 999078, China
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2
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Buoninfante S, Milano M, Negri B, Plainaki C, Sindoni G, Fedi M. Gravity evidence for a heterogeneous crust of Mercury. Sci Rep 2023; 13:19854. [PMID: 37963890 PMCID: PMC10646127 DOI: 10.1038/s41598-023-46081-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 10/27/2023] [Indexed: 11/16/2023] Open
Abstract
We modeled gravity data to explore Mercury's internal structure and show the presence of crustal heterogeneities in density. We first evaluated the lithospheric flexure occurring in the spherical harmonic degree range 5-80, according to the flexural isostatic response curve. We thus estimated a mean elastic lithosphere thickness of about 30 [Formula: see text] 10 km and modeled the crust-mantle interface, which varies from 19 to 42 km depth, according to a flexural compensation model. The isostatic gravity anomalies were then obtained as the residual field with respect to the contributions from topography and lithospheric flexure. Isostatic anomalies are mainly related to density variations in the crust: gravity highs mostly correspond to large-impact basins suggesting intra-crustal magmatic intrusions as the main origin of these anomalies. Isostatic gravity lows prevail, instead, above intercrater plains and may represent the signature of a heavily fractured crust.
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Affiliation(s)
- Salvatore Buoninfante
- Department of Earth, Environment and Resources Sciences, Università degli Studi di Napoli Federico II, Naples, Italy
- Istituto di Astrofisica e Planetologia Spaziali (IAPS), INAF, Rome, Italy
| | - Maurizio Milano
- Department of Earth, Environment and Resources Sciences, Università degli Studi di Napoli Federico II, Naples, Italy.
| | | | | | | | - Maurizio Fedi
- Department of Earth, Environment and Resources Sciences, Università degli Studi di Napoli Federico II, Naples, Italy
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3
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Siegler MA, Feng J, Lehman-Franco K, Andrews-Hanna JC, Economos RC, Clair MS, Million C, Head JW, Glotch TD, White MN. Remote detection of a lunar granitic batholith at Compton-Belkovich. Nature 2023; 620:116-121. [PMID: 37407821 DOI: 10.1038/s41586-023-06183-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 05/09/2023] [Indexed: 07/07/2023]
Abstract
Granites are nearly absent in the Solar System outside of Earth. Achieving granitic compositions in magmatic systems requires multi-stage melting and fractionation, which also increases the concentration of radiogenic elements1. Abundant water and plate tectonics facilitate these processes on Earth, aiding in remelting. Although these drivers are absent on the Moon, small granite samples have been found, but details of their origin and the scale of systems they represent are unknown2. Here we report microwave-wavelength measurements of an anomalously hot geothermal source that is best explained by the presence of an approximately 50-kilometre-diameter granitic system below the thorium-rich farside feature known as Compton-Belkovich. Passive microwave radiometry is sensitive to the integrated thermal gradient to several wavelengths depth. The 3-37-gigahertz antenna temperatures of the Chang'e-1 and Chang'e-2 microwave instruments allow us to measure a peak heat flux of about 180 milliwatts per square metre, which is about 20 times higher than that of the average lunar highlands3,4. The surprising magnitude and geographic extent of this feature imply an Earth-like, evolved granitic system larger than believed possible on the Moon, especially outside of the Procellarum region5. Furthermore, these methods are generalizable: similar uses of passive radiometric data could vastly expand our knowledge of geothermal processes on the Moon and other planetary bodies.
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Affiliation(s)
- Matthew A Siegler
- Planetary Science Institute, Tucson, AZ, USA.
- Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA.
| | - Jianqing Feng
- Planetary Science Institute, Tucson, AZ, USA.
- Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA.
| | | | - Jeffrey C Andrews-Hanna
- Department of Planetary Sciences/Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
| | - Rita C Economos
- Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA
| | | | | | - James W Head
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, USA
| | - Timothy D Glotch
- Department of Geosciences, SUNY Stony Brook, Stony Brook, NY, USA
| | - Mackenzie N White
- Department of Earth Sciences, Southern Methodist University, Dallas, TX, USA
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4
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Goossens S, Fernández Mora Á, Heijkoop E, Sabaka TJ. Patched Local Lunar Gravity Solutions Using GRAIL Data. EARTH AND SPACE SCIENCE (HOBOKEN, N.J.) 2021; 8:e2021EA001695. [PMID: 34820481 PMCID: PMC8596444 DOI: 10.1029/2021ea001695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 09/05/2021] [Accepted: 10/03/2021] [Indexed: 06/13/2023]
Abstract
We present a method to determine local gravity fields for the Moon using Gravity Recovery and Interior Laboratory (GRAIL) data. We express gravity as gridded gravity anomalies on a sphere, and we estimate adjustments to a background global start model expressed in spherical harmonics. We processed GRAIL Ka-band range-rate data with a short-arc approach, using only data over the area of interest. We determine our gravity solutions using neighbor smoothing constraints. We divided the entire Moon into 12 regions and 2 polar caps, with a resolution of 0.15 ° × 0.15 ° (which is equivalent to degree and order 1199 in spherical harmonics), and determined the optimal smoothing parameter for each area by comparing localized correlations between gravity and topography for each solution set. Our selected areas share nodes with surrounding areas and they are overlapping. To mitigate boundary effects, we patch the solutions together by symmetrically omitting the boundary parts of overlapping solutions. Our new solution has been iterated, and it has improved correlations with topography when compared to a fully iterated global model. Our method requires fewer resources, and can easily handle regionally varying resolution or constraints. The smooth model describes small-scale features clearly, and can be used in local studies of the structure of the lunar crust.
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Affiliation(s)
- Sander Goossens
- Center for Space Sciences and TechnologyUniversity of MarylandBaltimoreMDUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Center for Research and Exploration in Space Science and Technology (CRESST) IINASA/GSFCGreenbeltMDUSA
- Now at Planetary Geology, Geophysics, and Geochemistry LaboratoryNASA Goddard Space Flight CenterGreenbeltMDUSA
| | - Álvaro Fernández Mora
- Center for Space Sciences and TechnologyUniversity of MarylandBaltimoreMDUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Center for Research and Exploration in Space Science and Technology (CRESST) IINASA/GSFCGreenbeltMDUSA
- Faculty of Aerospace EngineeringDelft University of TechnologyDelftThe Netherlands
- Now at Faculty of Mathematics and Computer ScienceUniversity of BarcelonaBarcelonaSpain
| | - Eduard Heijkoop
- Center for Space Sciences and TechnologyUniversity of MarylandBaltimoreMDUSA
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Center for Research and Exploration in Space Science and Technology (CRESST) IINASA/GSFCGreenbeltMDUSA
- Faculty of Aerospace EngineeringDelft University of TechnologyDelftThe Netherlands
- Now at The Colorado Center for Astrodynamics Research and the Earth Science and Observation Center of the Cooperative Institute for Research in Environmental Sciences at the University of ColoradoBoulderCOUSA
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5
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Watters TR, James PB, Selvans MM. Mercury's Crustal Thickness and Contractional Strain. GEOPHYSICAL RESEARCH LETTERS 2021; 48:e2021GL093528. [PMID: 35860428 PMCID: PMC9285554 DOI: 10.1029/2021gl093528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 06/15/2023]
Abstract
The crust of Mercury has experienced contraction on a global scale. Contractional deformation is expressed by a broadly distributed network of lobate thrust fault scarps. The most likely principal source of stress is global contraction from cooling of Mercury's interior. Global contraction alone would be expected to result in a uniformly distributed population of thrust faults. Mercury's fault scarps, however, often occur in long, linear clusters or bands. An analysis of the contractional strain as a function of crustal thickness, estimated in two crustal thickness models (CT1 and CT2) derived from gravity and topography data obtained during the MESSENGER mission, indicates the greatest contractional strain occurs in crust 50-60 km thick. On Earth, mantle downwelling can thicken and compress overlying crust, regionally concentrating thrust faults. Clusters of lobate scarps collocated with regions of thick crust suggest downward mantle flow contributed to the localization of lithosphere-penetrating thrust faults.
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Affiliation(s)
- Thomas R. Watters
- Center for Earth and Planetary StudiesNational Air and Space MuseumSmithsonian InstitutionWashingtonDCUSA
| | | | - Michelle M. Selvans
- Center for Earth and Planetary StudiesNational Air and Space MuseumSmithsonian InstitutionWashingtonDCUSA
- Geology DepartmentClovis Community CollegeFresnoCAUSA
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6
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Knapmeyer-Endrun B, Panning MP, Bissig F, Joshi R, Khan A, Kim D, Lekić V, Tauzin B, Tharimena S, Plasman M, Compaire N, Garcia RF, Margerin L, Schimmel M, Stutzmann É, Schmerr N, Bozdağ E, Plesa AC, Wieczorek MA, Broquet A, Antonangeli D, McLennan SM, Samuel H, Michaut C, Pan L, Smrekar SE, Johnson CL, Brinkman N, Mittelholz A, Rivoldini A, Davis PM, Lognonné P, Pinot B, Scholz JR, Stähler S, Knapmeyer M, van Driel M, Giardini D, Banerdt WB. Thickness and structure of the martian crust from InSight seismic data. Science 2021; 373:438-443. [PMID: 34437117 DOI: 10.1126/science.abf8966] [Citation(s) in RCA: 68] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 05/21/2021] [Indexed: 11/02/2022]
Abstract
A planet's crust bears witness to the history of planetary formation and evolution, but for Mars, no absolute measurement of crustal thickness has been available. Here, we determine the structure of the crust beneath the InSight landing site on Mars using both marsquake recordings and the ambient wavefield. By analyzing seismic phases that are reflected and converted at subsurface interfaces, we find that the observations are consistent with models with at least two and possibly three interfaces. If the second interface is the boundary of the crust, the thickness is 20 ± 5 kilometers, whereas if the third interface is the boundary, the thickness is 39 ± 8 kilometers. Global maps of gravity and topography allow extrapolation of this point measurement to the whole planet, showing that the average thickness of the martian crust lies between 24 and 72 kilometers. Independent bulk composition and geodynamic constraints show that the thicker model is consistent with the abundances of crustal heat-producing elements observed for the shallow surface, whereas the thinner model requires greater concentration at depth.
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Affiliation(s)
- Brigitte Knapmeyer-Endrun
- Bensberg Observatory, University of Cologne, Vinzenz-Pallotti-Str. 26, 51429 Bergisch Gladbach, Germany.
| | - Mark P Panning
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 183-301, Pasadena, CA 91109, USA
| | - Felix Bissig
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - Rakshit Joshi
- Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Amir Khan
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland.,Physik-Institut, University of Zurich, Zurich, Switzerland
| | - Doyeon Kim
- Department of Geology, University of Maryland, College Park, 8000 Regents Dr., College Park, MD, 20782-4211, USA
| | - Vedran Lekić
- Department of Geology, University of Maryland, College Park, 8000 Regents Dr., College Park, MD, 20782-4211, USA
| | - Benoit Tauzin
- Université de Lyon, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, Université Jean Monet, CNRS, Laboratoire de Géologie de Lyon, Terre, Planètes, Environnement, F-69622 Villeurbanne, France.,Research School of Earth Sciences, The Australian National University, Canberra, ACT 0200, Australia
| | - Saikiran Tharimena
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 183-301, Pasadena, CA 91109, USA
| | - Matthieu Plasman
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, 1 rue Jussieu, F-75005 Paris, France
| | - Nicolas Compaire
- Institut Supérieur de l'Aéronautique et de l'Espace SUPAERO, 10 Avenue Edouard Belin, 31400 Toulouse, France
| | - Raphael F Garcia
- Institut Supérieur de l'Aéronautique et de l'Espace SUPAERO, 10 Avenue Edouard Belin, 31400 Toulouse, France
| | - Ludovic Margerin
- Institut de Recherche en Astrophysique et Planétologie, Université Toulouse III Paul Sabatier, CNRS, CNES, 14 Av. E. Belin, 31400 Toulouse, France
| | | | - Éléonore Stutzmann
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, 1 rue Jussieu, F-75005 Paris, France
| | - Nicholas Schmerr
- Department of Geology, University of Maryland, College Park, 8000 Regents Dr., College Park, MD, 20782-4211, USA
| | - Ebru Bozdağ
- Department of Geophysics, Colorado School of Mines, 1500 Illinois St., Golden, CO 80401, USA
| | - Ana-Catalina Plesa
- Institute of Planetary Research, German Aerospace Center (DLR), 12489 Berlin, Germany
| | - Mark A Wieczorek
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, 06304 Nice, France
| | - Adrien Broquet
- Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA.,Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, 06304 Nice, France
| | - Daniele Antonangeli
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France
| | - Scott M McLennan
- Department of Geosciences, Stony Brook University, Stony Brook, NY 11794-2100, USA
| | - Henri Samuel
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, 1 rue Jussieu, F-75005 Paris, France
| | - Chloé Michaut
- Université de Lyon, Ecole Normale Supérieure de Lyon, Université Claude Bernard Lyon 1, Université Jean Monet, CNRS, Laboratoire de Géologie de Lyon, Terre, Planètes, Environnement, F-69007 Lyon, France.,Institut Universitaire de France, Paris, France
| | - Lu Pan
- Center for Star and Planet Formation, GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
| | - Suzanne E Smrekar
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 183-301, Pasadena, CA 91109, USA
| | - Catherine L Johnson
- Department of Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.,Planetary Science Institute, Tucson, 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719-2395, USA
| | - Nienke Brinkman
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - Anna Mittelholz
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | | | - Paul M Davis
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095, USA
| | - Philippe Lognonné
- Université de Paris, Institut de Physique du Globe de Paris, CNRS, 1 rue Jussieu, F-75005 Paris, France.,Institut Universitaire de France, Paris, France
| | - Baptiste Pinot
- Institut Supérieur de l'Aéronautique et de l'Espace SUPAERO, 10 Avenue Edouard Belin, 31400 Toulouse, France
| | - John-Robert Scholz
- Max Planck Institute for Solar System Research, Justus-von-Liebig-Weg 3, 37077 Göttingen, Germany
| | - Simon Stähler
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - Martin Knapmeyer
- Institute of Planetary Research, German Aerospace Center (DLR), 12489 Berlin, Germany
| | - Martin van Driel
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - Domenico Giardini
- Institute of Geophysics, ETH Zurich, Sonneggstr. 5, 8092 Zürich, Switzerland
| | - W Bruce Banerdt
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., M/S 183-301, Pasadena, CA 91109, USA
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Ojha L, Buffo J, Karunatillake S, Siegler M. Groundwater production from geothermal heating on early Mars and implication for early martian habitability. SCIENCE ADVANCES 2020; 6:6/49/eabb1669. [PMID: 33268366 PMCID: PMC7710363 DOI: 10.1126/sciadv.abb1669] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 10/19/2020] [Indexed: 06/12/2023]
Abstract
In explaining extensive evidence for past liquid water, the debate on whether Mars was primarily warm and wet or cold and arid 4 billion years (Ga) ago has continued for decades. The Sun's luminosity was ~30% lower 4 Ga ago; thus, most martian climate models struggle to elevate the mean surface temperature past the melting point of water. Basal melting of ice sheets may help resolve that paradox. We modeled the thermophysical evolution of ice and estimate the geothermal heat flux required to produce meltwater on a cold, arid Mars. We then analyzed geophysical and geochemical data, showing that basal melting would have been feasible on Mars 4 Ga ago. If Mars were warm and wet 4 Ga ago, then the geothermal flux would have even sustained hydrothermal activity. Regardless of the actual nature of the ancient martian climate, the subsurface would have been the most habitable region on Mars.
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Affiliation(s)
- Lujendra Ojha
- Department of Earth and Planetary Sciences, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA.
| | - Jacob Buffo
- Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
| | - Suniti Karunatillake
- Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70802, USA
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8
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Chisenga C, Yan J, Zhao J, Deng Q, Barriot JP. Density Structure of the Von Kármán Crater in the Northwestern South Pole-Aitken Basin: Initial Subsurface Interpretation of the Chang'E-4 Landing Site Region. SENSORS (BASEL, SWITZERLAND) 2019; 19:E4445. [PMID: 31615029 PMCID: PMC6832371 DOI: 10.3390/s19204445] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 10/07/2019] [Accepted: 10/09/2019] [Indexed: 11/17/2022]
Abstract
The Von Kármán Crater, within the South Pole-Aitken (SPA) Basin, is the landing site of China's Chang'E-4 mission. To complement the in situ exploration mission and provide initial subsurface interpretation, we applied a 3D density inversion using the Gravity Recovery and Interior Laboratory (GRAIL) gravity data. We constrain our inversion method using known geological and geophysical lunar parameters to reduce the non-uniqueness associated with gravity inversion. The 3D density models reveal vertical and lateral density variations, 2600-3200 kg/m3, assigned to the changing porosity beneath the Von Kármán Crater. We also identify two mass excess anomalies in the crust with a steep density contrast of 150 kg/m3, which were suggested to have been caused by multiple impact cratering. The anomalies from recovered near surface density models, together with the gravity derivative maps extending to the lower crust, are consistent with surface geological manifestation of excavated mantle materials from remote sensing studies. Therefore, we suggest that the density distribution of the Von Kármán Crater indicates multiple episodes of impact cratering that resulted in formation and destruction of ancient craters, with crustal reworking and excavation of mantle materials.
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Affiliation(s)
- Chikondi Chisenga
- State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, Box 129, Luoyu Road, Wuhan 430070, China.
- Department of Earth Sciences, Ndata School of Climate and Earth Sciences, Malawi University of Science and Technology, Limbe P.O. Box 5196, Malawi.
| | - Jianguo Yan
- State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, Box 129, Luoyu Road, Wuhan 430070, China.
| | - Jiannan Zhao
- State Key Laboratory of Geological Process and Mineral Resources, Planetary Science Institute, China University of Geosciences, Wuhan 430074, China.
- School of Environmental Studies, China University of Geosciences, Wuhan 430074, China.
| | - Qingyun Deng
- State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, Box 129, Luoyu Road, Wuhan 430070, China.
| | - Jean-Pierre Barriot
- State Key Laboratory of Information Engineering in Surveying, Mapping and Remote Sensing (LIESMARS), Wuhan University, Box 129, Luoyu Road, Wuhan 430070, China.
- Geodesy Observatory of Tahiti, BP 6570, Faa'a 98702, Tahiti, French Polynesia.
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9
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Deutsch AN, Neumann GA, Head JW, Wilson L. GRAIL-identified gravity anomalies in Oceanus Procellarum: Insight into subsurface impact and magmatic structures on the Moon. ICARUS 2019; 331:192-208. [PMID: 32550742 PMCID: PMC7302338 DOI: 10.1016/j.icarus.2019.05.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Four, quasi-circular, positive Bouguer gravity anomalies (PBGAs) that are similar in diameter (~90-190 km) and gravitational amplitude (>140 mGal contrast) are identified within the central Oceanus Procellarum region of the Moon. These spatially associated PBGAs are located south of Aristarchus Plateau, north of Flamsteed crater, and two are within the Marius Hills volcanic complex (north and south). Each is characterized by distinct surface geologic features suggestive of ancient impact craters and/or volcanic/plutonic activity. Here, we combine geologic analyses with forward modeling of high-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) mission in order to constrain the subsurface structures that contribute to these four PBGAs. The GRAIL data presented here, at spherical harmonic degrees 6-660, permit higher resolution analyses of these anomalies than previously reported, and reveal new information about subsurface structures. Specifically, we find that the amplitudes of the four PBGAs cannot be explained solely by mare-flooded craters, as suggested in previous work; an additional density contrast is required to explain the high-amplitude of the PBGAs. For Northern Flamsteed (190 km diameter), the additional density contrast may be provided by impact-related mantle uplift. If the local crust has a density ~2800 kg/m3, then ~7 km of uplift is required for this anomaly, although less uplift is required if the local crust has a lower mean density of ~2500 kg/m3. For the Northern and Southern Marius Hills anomalies, the additional density contrast is consistent with the presence of a crustal complex of vertical dikes that occupies up to ~37% of the regionally thin crust. The structure of Southern Aristarchus Plateau (90 km diameter), an anomaly with crater-related topographic structures, remains ambiguous. Based on the relatively small size of the anomaly, we do not favor mantle uplift, however understanding mantle response in a region of especially thin crust needs to be better resolved. It is more likely that this anomaly is due to subsurface magmatic material given the abundance of volcanic material in the surrounding region. Overall, the four PBGAs analyzed here are important in understanding the impact and volcanic/plutonic history of the Moon, specifically in a region of thin crust and elevated temperatures characteristic of the Procellarum KREEP Terrane.
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Affiliation(s)
- Ariel N. Deutsch
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | | | - James W. Head
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - Lionel Wilson
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI 02912, USA
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
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10
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Genova A, Goossens S, Mazarico E, Lemoine FG, Neumann GA, Kuang W, Sabaka TJ, Hauck SA, Smith DE, Solomon SC, Zuber MT. Geodetic evidence that Mercury has a solid inner core. GEOPHYSICAL RESEARCH LETTERS 2019; 46:3625-3633. [PMID: 31359894 PMCID: PMC6662718 DOI: 10.1029/2018gl081135] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 03/10/2019] [Indexed: 06/10/2023]
Abstract
Geodetic analysis of radio tracking measurements of the MESSENGER spacecraft while in orbit about Mercury has yielded new estimates for the planet's gravity field, tidal Love number, and pole coordinates. The derived right ascension (α = 281.0082° ± 0.0009°; all uncertainties are 3 standard deviations) and declination (δ =61.4164° ± 0.0003°) of the spin pole place Mercury in the Cassini state. Confirmation of the equilibrium state with an estimated mean (whole-planet) obliquity ϵ of 1.968 ± 0.027 arcmin enables the confident determination of the planet's normalized polar moment of inertia (0.333 ± 0.005), which indicates a high degree of internal differentiation. Internal structure models generated by a Markov-Chain Monte Carlo process and consistent with the geodetic constraints possess a solid inner core with a radius (r ic ) between 0.3 and 0.7 that of the outer core (r oc ).
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Affiliation(s)
- Antonio Genova
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology
- NASA Goddard Space Flight Center
| | - Sander Goossens
- Center for Research and Exploration in Space Science and Technology, University of Maryland, Baltimore County
- NASA Goddard Space Flight Center
| | | | | | | | | | | | - Steven A Hauck
- Department of Earth, Environmental, and Planetary Sciences, Case Western Reserve University
| | - David E Smith
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology
| | | | - Maria T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology
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11
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Andrews-Hanna JC, Head JW, Johnson B, Keane JT, Kiefer WS, McGovern PJ, Neumann GA, Wieczorek MA, Zuber MT. Ring faults and ring dikes around the Orientale basin on the Moon. ICARUS 2018; 310:1-20. [PMID: 29755136 PMCID: PMC5939591 DOI: 10.1016/j.icarus.2017.12.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The Orientale basin is the youngest and best-preserved multiring impact basin on the Moon, having experienced only modest modification by subsequent impacts and volcanism. Orientale is often treated as the type example of a multiring basin, with three prominent rings outside of the inner depression: the Inner Rook Montes, the Outer Rook Montes, and the Cordillera. Here we use gravity data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission to reveal the subsurface structure of Orientale and its ring system. Gradients of the gravity data reveal a continuous ring dike intruded into the Outer Rook along the plane of the fault associated with the ring scarp. The volume of this ring dike is ~18 times greater than the volume of all extrusive mare deposits associated with the basin. The gravity gradient signature of the Cordillera ring indicates an offset along the fault across a shallow density interface, interpreted to be the base of the low-density ejecta blanket. Both gravity gradients and crustal thickness models indicate that the edge of the central cavity is shifted inward relative to the equivalent Inner Rook ring at the surface. Models of the deep basin structure show inflections along the crust-mantle interface at both the Outer Rook and Cordillera rings, indicating that the basin ring faults extend from the surface to at least the base of the crust. Fault dips range from 13-22° for the Cordillera fault in the northeastern quadrant, to 90° for the Outer Rook in the northwestern quadrant. The fault dips for both outer rings are lowest in the northeast, possibly due to the effects of either the direction of projectile motion or regional gradients in pre-impact crustal thickness. Similar ring dikes and ring faults are observed around the majority of lunar basins.
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Affiliation(s)
| | - James W Head
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - Brandon Johnson
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - James T Keane
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - Walter S Kiefer
- Lunar and Planetary Institute, University Space Research Association, Houston, TX 77058, USA
| | - Patrick J McGovern
- Lunar and Planetary Institute, University Space Research Association, Houston, TX 77058, USA
| | - Gregory A Neumann
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - Mark A Wieczorek
- Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, France
| | - Maria T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA
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12
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Goossens S, Sabaka TJ, Genova A, Mazarico E, Nicholas JB, Neumann GA. Evidence for a Low Bulk Crustal Density for Mars from Gravity and Topography. GEOPHYSICAL RESEARCH LETTERS 2017; 44:7686-7694. [PMID: 28966411 PMCID: PMC5619241 DOI: 10.1002/2017gl074172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Knowledge of the average density of the crust of a planet is important in determining its interior structure. The combination of high-resolution gravity and topography data has yielded a low density for the Moon's crust, yet for other terrestrial planets the resolution of the gravity field models has hampered reasonable estimates. By using well-chosen constraints derived from topography during gravity field model determination using satellite tracking data, we show that we can robustly and independently determine the average bulk crustal density directly from the tracking data, using the admittance between topography and imperfect gravity. We find a low average bulk crustal density for Mars, 2582 ± 209 kg m-3. This bulk crustal density is lower than that assumed until now. Densities for volcanic complexes are higher, consistent with earlier estimates, implying large lateral variations in crustal density. In addition, we find indications that the crustal density increases with depth.
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Affiliation(s)
- Sander Goossens
- CRESST, University of Maryland, Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250, USA
- NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
| | - Terence J. Sabaka
- NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
| | - Antonio Genova
- NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, 54-918, Cambridge, MA 02139, USA
| | - Erwan Mazarico
- NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
| | - Joseph B. Nicholas
- NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
- Emergent Space Technologies, 6411 Ivy Lane Suite 303, Greenbelt, MD 20770, USA
| | - Gregory A. Neumann
- NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771, USA
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13
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Abstract
Until the acquisition of in-situ measurements, the study of the present-day heat flow of Mars must rely on indirect methods, mainly based on the relation between the thermal state of the lithosphere and its mechanical strength, or on theoretical models of internal evolution. Here, we present a first-order global model for the present-day surface heat flow for Mars, based on the radiogenic heat production of the crust and mantle, on scaling of heat flow variations arising from crustal thickness and topography variations, and on the heat flow derived from the effective elastic thickness of the lithosphere beneath the North Polar Region. Our preferred model finds heat flows varying between 14 and 25 mW m-2, with an average value of 19 mW m-2. Similar results (although about ten percent higher) are obtained if we use heat flow based on the lithospheric strength of the South Polar Region. Moreover, expressing our results in terms of the Urey ratio (the ratio between total internal heat production and total heat loss through the surface), we estimate values close to 0.7-0.75, which indicates a moderate contribution of secular cooling to the heat flow of Mars (consistent with the low heat flow values deduced from lithosphere strength), unless heat-producing elements abundances for Mars are subchondritic.
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14
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Jansen JC, Andrews-Hanna JC, Li Y, Lucey PG, Taylor GJ, Goossens S, Lemoine FG, Mazarico E, Head JW, Milbury C, Kiefer WS, Soderblom JM, Zuber MT. Small-scale density variations in the lunar crust revealed by GRAIL. ICARUS 2016; 291:107-123. [PMID: 32908319 PMCID: PMC7477950 DOI: 10.1016/j.icarus.2017.03.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Data from the Gravity Recovery and Interior Laboratory (GRAIL) mission have revealed that ~98% of the power of the gravity signal of the Moon at high spherical harmonic degrees correlates with the topography. The remaining 2% of the signal, which cannot be explained by topography, contains information about density variations within the crust. These high-degree Bouguer gravity anomalies are likely caused by small-scale (10's of km) shallow density variations. Here we use gravity inversions to model the small-scale three-dimensional variations in the density of the lunar crust. Inversion results from three non-descript areas yield shallow density variations in the range of 100-200 kg/m3. Three end-member scenarios of variations in porosity, intrusions into the crust, and variations in bulk crustal composition were tested as possible sources of the density variations. We find that the density anomalies can be caused entirely by changes in porosity. Characteristics of density anomalies in the South Pole-Aitken basin also support porosity as a primary source of these variations. Mafic intrusions into the crust could explain many, but not all of the anomalies. Additionally, variations in crustal composition revealed by spectral data could only explain a small fraction of the density anomalies. Nevertheless, all three sources of density variations likely contribute. Collectively, results from this study of GRAIL gravity data, combined with other studies of remote sensing data and lunar samples, show that the lunar crust exhibits variations in density by ±10% over scales ranging from centimeters to 100's of kilometers.
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Affiliation(s)
- J C Jansen
- Department of Geophysics, Colorado School of Mines, Golden, CO 80401
| | | | - Y Li
- Department of Geophysics, Colorado School of Mines, Golden, CO 80401
| | - P G Lucey
- Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, HI 96822
| | - G J Taylor
- Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, HI 96822
| | - S Goossens
- NASA Goddard Space Flight Center, Greenbelt, MD 20771
| | - F G Lemoine
- NASA Goddard Space Flight Center, Greenbelt, MD 20771
| | - E Mazarico
- NASA Goddard Space Flight Center, Greenbelt, MD 20771
| | - J W Head
- Department of Geological Sciences, Brown University, Providence, RI 02912
| | - C Milbury
- Purdue University. West Lafayette, IN 47907
| | - W S Kiefer
- Lunar and Planetary Institute, Houston TX 77058
| | - J M Soderblom
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
| | - M T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139
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15
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Neumann GA, Zuber MT, Wieczorek MA, Head JW, Baker DMH, Solomon SC, Smith DE, Lemoine FG, Mazarico E, Sabaka TJ, Goossens SJ, Melosh HJ, Phillips RJ, Asmar SW, Konopliv AS, Williams JG, Sori MM, Soderblom JM, Miljković K, Andrews-Hanna JC, Nimmo F, Kiefer WS. Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements. SCIENCE ADVANCES 2015; 1:e1500852. [PMID: 26601317 PMCID: PMC4646831 DOI: 10.1126/sciadv.1500852] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/18/2015] [Indexed: 05/30/2023]
Abstract
Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in the gravitational signature of lunar impact structures at the morphological transition, with increasing diameter, from complex craters to peak-ring basins. At crater diameters larger than ~200 km, a central positive Bouguer anomaly is seen within the innermost peak ring, and an annular negative Bouguer anomaly extends outward from this ring to the outer topographic rim crest. These observations demonstrate that basin-forming impacts remove crustal materials from within the peak ring and thicken the crust between the peak ring and the outer rim crest. A correlation between the diameter of the central Bouguer gravity high and the outer topographic ring diameter for well-preserved basins enables the identification and characterization of basins for which topographic signatures have been obscured by superposed cratering and volcanism. The GRAIL inventory of lunar basins improves upon earlier lists that differed in their totals by more than a factor of 2. The size-frequency distributions of basins on the nearside and farside hemispheres of the Moon differ substantially; the nearside hosts more basins larger than 350 km in diameter, whereas the farside has more smaller basins. Hemispherical differences in target properties, including temperature and porosity, are likely to have contributed to these different distributions. Better understanding of the factors that control basin size will help to constrain models of the original impactor population.
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Affiliation(s)
- Gregory A. Neumann
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - Maria T. Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Mark A. Wieczorek
- Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, CNRS, Paris 75013, France
| | - James W. Head
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - David M. H. Baker
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI 02912, USA
| | - Sean C. Solomon
- Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, USA
- Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington, DC 20015, USA
| | - David E. Smith
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Frank G. Lemoine
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - Erwan Mazarico
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - Terence J. Sabaka
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
| | - Sander J. Goossens
- Center for Research and Exploration in Space Science and Technology, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - H. Jay Melosh
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Roger J. Phillips
- Planetary Science Directorate, Southwest Research Institute, Boulder, CO 80302, USA
| | - Sami W. Asmar
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109–8099, USA
| | - Alexander S. Konopliv
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109–8099, USA
| | - James G. Williams
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109–8099, USA
| | - Michael M. Sori
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jason M. Soderblom
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Katarina Miljković
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jeffrey C. Andrews-Hanna
- Department of Geophysics and Center for Space Resources, Colorado School of Mines, Golden, CO 80401, USA
| | - Francis Nimmo
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
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16
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Andrews-Hanna JC, Besserer J, Head JW, Howett CJA, Kiefer WS, Lucey PJ, McGovern PJ, Melosh HJ, Neumann GA, Phillips RJ, Schenk PM, Smith DE, Solomon SC, Zuber MT. Structure and evolution of the lunar Procellarum region as revealed by GRAIL gravity data. Nature 2014; 514:68-71. [PMID: 25279919 DOI: 10.1038/nature13697] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2014] [Accepted: 07/16/2014] [Indexed: 11/09/2022]
Abstract
The Procellarum region is a broad area on the nearside of the Moon that is characterized by low elevations, thin crust, and high surface concentrations of the heat-producing elements uranium, thorium, and potassium. The region has been interpreted as an ancient impact basin approximately 3,200 kilometres in diameter, although supporting evidence at the surface would have been largely obscured as a result of the great antiquity and poor preservation of any diagnostic features. Here we use data from the Gravity Recovery and Interior Laboratory (GRAIL) mission to examine the subsurface structure of Procellarum. The Bouguer gravity anomalies and gravity gradients reveal a pattern of narrow linear anomalies that border Procellarum and are interpreted to be the frozen remnants of lava-filled rifts and the underlying feeder dykes that served as the magma plumbing system for much of the nearside mare volcanism. The discontinuous surface structures that were earlier interpreted as remnants of an impact basin rim are shown in GRAIL data to be a part of this continuous set of border structures in a quasi-rectangular pattern with angular intersections, contrary to the expected circular or elliptical shape of an impact basin. The spatial pattern of magmatic-tectonic structures bounding Procellarum is consistent with their formation in response to thermal stresses produced by the differential cooling of the province relative to its surroundings, coupled with magmatic activity driven by the greater-than-average heat flux in the region.
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Affiliation(s)
- Jeffrey C Andrews-Hanna
- Department of Geophysics and Center for Space Resources, Colorado School of Mines, Golden, Colorado 80401, USA
| | - Jonathan Besserer
- Department of Earth and Planetary Sciences, University of California, Santa Cruz, California 95064, USA
| | - James W Head
- Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, Rhode Island 02912, USA
| | - Carly J A Howett
- Planetary Science Directorate, Southwest Research Institute, Boulder, Colorado 80302, USA
| | | | - Paul J Lucey
- Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, Hawaii 96822, USA
| | | | - H Jay Melosh
- Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, USA
| | - Gregory A Neumann
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA
| | - Roger J Phillips
- Planetary Science Directorate, Southwest Research Institute, Boulder, Colorado 80302, USA
| | - Paul M Schenk
- Lunar and Planetary Institute, Houston, Texas 77058, USA
| | - David E Smith
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA
| | - Sean C Solomon
- 1] Department of Terrestrial Magnetism, Carnegie Institution of Washington, Washington DC 20015, USA [2] Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA
| | - Maria T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, USA
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Crawford IA, Joy KH. Lunar exploration: opening a window into the history and evolution of the inner Solar System. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2014; 372:20130315. [PMID: 25114318 PMCID: PMC4128274 DOI: 10.1098/rsta.2013.0315] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The lunar geological record contains a rich archive of the history of the inner Solar System, including information relevant to understanding the origin and evolution of the Earth-Moon system, the geological evolution of rocky planets, and our local cosmic environment. This paper provides a brief review of lunar exploration to-date and describes how future exploration initiatives will further advance our understanding of the origin and evolution of the Moon, the Earth-Moon system and of the Solar System more generally. It is concluded that further advances will require the placing of new scientific instruments on, and the return of additional samples from, the lunar surface. Some of these scientific objectives can be achieved robotically, for example by in situ geochemical and geophysical measurements and through carefully targeted sample return missions. However, in the longer term, we argue that lunar science would greatly benefit from renewed human operations on the surface of the Moon, such as would be facilitated by implementing the recently proposed Global Exploration Roadmap.
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Affiliation(s)
- Ian A Crawford
- Department of Earth and Planetary Sciences, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK Centre for Planetary Sciences at UCL/Birkbeck, Gower Street, London WC1E 6BT, UK
| | - Katherine H Joy
- School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Williamson Building, Oxford Road, Manchester M13 9PL, UK
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18
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Taylor GJ, Wieczorek MA. Lunar bulk chemical composition: a post-Gravity Recovery and Interior Laboratory reassessment. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2014; 372:20130242. [PMID: 25114309 PMCID: PMC4128265 DOI: 10.1098/rsta.2013.0242] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
New estimates of the thickness of the lunar highlands crust based on data from the Gravity Recovery and Interior Laboratory mission, allow us to reassess the abundances of refractory elements in the Moon. Previous estimates of the Moon fall into two distinct groups: earthlike and a 50% enrichment in the Moon compared with the Earth. Revised crustal thicknesses and compositional information from remote sensing and lunar samples indicate that the crust contributes 1.13-1.85 wt% Al2O3 to the bulk Moon abundance. Mare basalt Al2O3 concentrations (8-10 wt%) and Al2O3 partitioning behaviour between melt and pyroxene during partial melting indicate mantle Al2O3 concentration in the range 1.3-3.1 wt%, depending on the relative amounts of pyroxene and olivine. Using crustal and mantle mass fractions, we show that that the Moon and the Earth most likely have the same (within 20%) concentrations of refractory elements. This allows us to use correlations between pairs of refractory and volatile elements to confirm that lunar abundances of moderately volatile elements such as K, Rb and Cs are depleted by 75% in the Moon compared with the Earth and that highly volatile elements, such as Tl and Cd, are depleted by 99%. The earthlike refractory abundances and depleted volatile abundances are strong constraints on lunar formation processes.
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Affiliation(s)
- G Jeffrey Taylor
- Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, Honolulu, HI 96822, USA
| | - Mark A Wieczorek
- Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, Case 7071, Lamarck A, 35 rue Hélène Brion, Paris Cedex 13 75205, France
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19
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Lemoine FG, Goossens S, Sabaka TJ, Nicholas JB, Mazarico E, Rowlands DD, Loomis BD, Chinn DS, Neumann GA, Smith DE, Zuber MT. GRGM900C: A degree 900 lunar gravity model from GRAIL primary and extended mission data. GEOPHYSICAL RESEARCH LETTERS 2014; 41:3382-3389. [PMID: 26074638 PMCID: PMC4459205 DOI: 10.1002/2014gl060027] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 04/27/2014] [Indexed: 05/05/2023]
Abstract
We have derived a gravity field solution in spherical harmonics to degree and order 900, GRGM900C, from the tracking data of the Gravity Recovery and Interior Laboratory (GRAIL) Primary (1 March to 29 May 2012) and Extended Missions (30 August to 14 December 2012). A power law constraint of 3.6 ×10-4/ℓ2 was applied only for degree ℓ greater than 600. The model produces global correlations of gravity, and gravity predicted from lunar topography of ≥ 0.98 through degree 638. The model's degree strength varies from a minimum of 575-675 over the central nearside and farside to 900 over the polar regions. The model fits the Extended Mission Ka-Band Range Rate data through 17 November 2012 at 0.13 μm/s RMS, whereas the last month of Ka-Band Range-Rate data obtained from altitudes of 2-10 km fit at 0.98 μm/s RMS, indicating that there is still signal inherent in the tracking data beyond degree 900.
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Affiliation(s)
| | - Sander Goossens
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; CRESST, University of Maryland, Baltimore County Baltimore, Maryland, USA
| | | | - Joseph B Nicholas
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; Emergent Space Technologies Greenbelt, Maryland, USA
| | - Erwan Mazarico
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, Massachusetts, USA
| | | | - Bryant D Loomis
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; Stinger Ghaffarian Technologies Inc. Greenbelt, Maryland, USA
| | - Douglas S Chinn
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; Stinger Ghaffarian Technologies Inc. Greenbelt, Maryland, USA
| | | | - David E Smith
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, Massachusetts, USA
| | - Maria T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, Massachusetts, USA
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20
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Goossens S, Sabaka TJ, Nicholas JB, Lemoine FG, Rowlands DD, Mazarico E, Neumann GA, Smith DE, Zuber MT. High-resolution local gravity model of the south pole of the Moon from GRAIL extended mission data. GEOPHYSICAL RESEARCH LETTERS 2014; 41:3367-3374. [PMID: 26074637 PMCID: PMC4459178 DOI: 10.1002/2014gl060178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 05/08/2014] [Indexed: 06/04/2023]
Abstract
We estimated a high-resolution local gravity field model over the south pole of the Moon using data from the Gravity Recovery and Interior Laboratory's extended mission. Our solution consists of adjustments with respect to a global model expressed in spherical harmonics. The adjustments are expressed as gridded gravity anomalies with a resolution of 1/6° by 1/6° (equivalent to that of a degree and order 1080 model in spherical harmonics), covering a cap over the south pole with a radius of 40°. The gravity anomalies have been estimated from a short-arc analysis using only Ka-band range-rate (KBRR) data over the area of interest. We apply a neighbor-smoothing constraint to our solution. Our local model removes striping present in the global model; it reduces the misfit to the KBRR data and improves correlations with topography to higher degrees than current global models. KEY POINTS We present a high-resolution gravity model of the south pole of the Moon Improved correlations with topography to higher degrees than global models Improved fits to the data and reduced striping that is present in global models.
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Affiliation(s)
- Sander Goossens
- CRESST, University of Maryland Baltimore County Baltimore, Maryland, USA ; NASA Goddard Space Flight Center Greenbelt, Maryland, USA
| | | | - Joseph B Nicholas
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; Emergent Space Technologies Greenbelt, Maryland, USA
| | | | | | - Erwan Mazarico
- NASA Goddard Space Flight Center Greenbelt, Maryland, USA ; Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, Massachusetts, USA
| | | | - David E Smith
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, Massachusetts, USA
| | - Maria T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology Cambridge, Massachusetts, USA
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Wieczorek MA, Neumann GA, Nimmo F, Kiefer WS, Taylor GJ, Melosh HJ, Phillips RJ, Solomon SC, Andrews-Hanna JC, Asmar SW, Konopliv AS, Lemoine FG, Smith DE, Watkins MM, Williams JG, Zuber MT. The crust of the Moon as seen by GRAIL. Science 2012; 339:671-5. [PMID: 23223394 DOI: 10.1126/science.1231530] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
High-resolution gravity data obtained from the dual Gravity Recovery and Interior Laboratory (GRAIL) spacecraft show that the bulk density of the Moon's highlands crust is 2550 kilograms per cubic meter, substantially lower than generally assumed. When combined with remote sensing and sample data, this density implies an average crustal porosity of 12% to depths of at least a few kilometers. Lateral variations in crustal porosity correlate with the largest impact basins, whereas lateral variations in crustal density correlate with crustal composition. The low-bulk crustal density allows construction of a global crustal thickness model that satisfies the Apollo seismic constraints, and with an average crustal thickness between 34 and 43 kilometers, the bulk refractory element composition of the Moon is not required to be enriched with respect to that of Earth.
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Affiliation(s)
- Mark A Wieczorek
- Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, Case 7071, Lamarck A, 5, rue Thomas Mann, 75205 Paris Cedex 13, France.
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22
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Andrews-Hanna JC, Asmar SW, Head JW, Kiefer WS, Konopliv AS, Lemoine FG, Matsuyama I, Mazarico E, McGovern PJ, Melosh HJ, Neumann GA, Nimmo F, Phillips RJ, Smith DE, Solomon SC, Taylor GJ, Wieczorek MA, Williams JG, Zuber MT. Ancient igneous intrusions and early expansion of the Moon revealed by GRAIL gravity gradiometry. Science 2012; 339:675-8. [PMID: 23223393 DOI: 10.1126/science.1231753] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The earliest history of the Moon is poorly preserved in the surface geologic record due to the high flux of impactors, but aspects of that history may be preserved in subsurface structures. Application of gravity gradiometry to observations by the Gravity Recovery and Interior Laboratory (GRAIL) mission results in the identification of a population of linear gravity anomalies with lengths of hundreds of kilometers. Inversion of the gravity anomalies indicates elongated positive-density anomalies that are interpreted to be ancient vertical tabular intrusions or dikes formed by magmatism in combination with extension of the lithosphere. Crosscutting relationships support a pre-Nectarian to Nectarian age, preceding the end of the heavy bombardment of the Moon. The distribution, orientation, and dimensions of the intrusions indicate a globally isotropic extensional stress state arising from an increase in the Moon's radius by 0.6 to 4.9 kilometers early in lunar history, consistent with predictions of thermal models.
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Affiliation(s)
- Jeffrey C Andrews-Hanna
- Department of Geophysics and Center for Space Resources, Colorado School of Mines, Golden, CO 80401, USA.
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Zuber MT, Smith DE, Watkins MM, Asmar SW, Konopliv AS, Lemoine FG, Melosh HJ, Neumann GA, Phillips RJ, Solomon SC, Wieczorek MA, Williams JG, Goossens SJ, Kruizinga G, Mazarico E, Park RS, Yuan DN. Gravity field of the Moon from the Gravity Recovery and Interior Laboratory (GRAIL) mission. Science 2012; 339:668-71. [PMID: 23223395 DOI: 10.1126/science.1231507] [Citation(s) in RCA: 317] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Spacecraft-to-spacecraft tracking observations from the Gravity Recovery and Interior Laboratory (GRAIL) have been used to construct a gravitational field of the Moon to spherical harmonic degree and order 420. The GRAIL field reveals features not previously resolved, including tectonic structures, volcanic landforms, basin rings, crater central peaks, and numerous simple craters. From degrees 80 through 300, over 98% of the gravitational signature is associated with topography, a result that reflects the preservation of crater relief in highly fractured crust. The remaining 2% represents fine details of subsurface structure not previously resolved. GRAIL elucidates the role of impact bombardment in homogenizing the distribution of shallow density anomalies on terrestrial planetary bodies.
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Affiliation(s)
- Maria T Zuber
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139-4307, USA.
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24
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Beuthe M, Le Maistre S, Rosenblatt P, Pätzold M, Dehant V. Density and lithospheric thickness of the Tharsis Province from MEX MaRS and MRO gravity data. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011je003976] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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25
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Zuber MT, Lemoine FG, Smith DE, Konopliv AS, Smrekar SE, Asmar SW. Mars Reconnaissance Orbiter Radio Science Gravity Investigation. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006je002833] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Belleguic V, Lognonné P, Wieczorek M. Constraints on the Martian lithosphere from gravity and topography data. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005je002437] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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28
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McGovern PJ. Correction to “Localized gravity/topography admittance and correlation spectra on Mars: Implications for regional and global evolution”. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004je002286] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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29
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Wieczorek MA. Thickness of the Martian crust: Improved constraints from geoid-to-topography ratios. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003je002153] [Citation(s) in RCA: 182] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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30
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Montési LGJ. Clues to the lithospheric structure of Mars from wrinkle ridge sets and localization instability. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002je001974] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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McGovern PJ, Solomon SC, Smith DE, Zuber MT, Simons M, Wieczorek MA, Phillips RJ, Neumann GA, Aharonson O, Head JW. Localized gravity/topography admittance and correlation spectra on Mars: Implications for regional and global evolution. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2002je001854] [Citation(s) in RCA: 214] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Sean C. Solomon
- Department of Terrestrial Magnetism; Carnegie Institution of Washington; Washington D.C. USA
| | | | - Maria T. Zuber
- Department of Earth, Atmospheric, and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
| | - Mark Simons
- Division of Geological and Planetary Sciences; California Institute of Technology; Pasadena California USA
| | - Mark A. Wieczorek
- Department of Earth, Atmospheric, and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
| | - Roger J. Phillips
- Department of Earth and Planetary Sciences; Washington University; St. Louis Missouri USA
| | - Gregory A. Neumann
- Department of Earth, Atmospheric, and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
| | - Oded Aharonson
- Department of Earth, Atmospheric, and Planetary Sciences; Massachusetts Institute of Technology; Cambridge Massachusetts USA
| | - James W. Head
- Department of Geological Sciences; Brown University; Providence Rhode Island USA
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Nimmo F. Admittance estimates of mean crustal thickness and density at the Martian hemispheric dichotomy. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2000je001488] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Francis Nimmo
- Department of Geological Sciences; University College London; London UK
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Wieczorek MA, Zuber MT. A Serenitatis origin for the Imbrian grooves and South Pole-Aitken thorium anomaly. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001384] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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35
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Pieters CM, Head JW, Gaddis L, Jolliff B, Duke M. Rock types of South Pole-Aitken basin and extent of basaltic volcanism. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000je001414] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Wieczorek MA, Phillips RJ. The “Procellarum KREEP Terrane”: Implications for mare volcanism and lunar evolution. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001092] [Citation(s) in RCA: 235] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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38
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Zuber MT, Solomon SC, Phillips RJ, Smith DE, Tyler GL, Aharonson O, Balmino G, Banerdt WB, Head JW, Johnson CL, Lemoine FG, McGovern PJ, Neumann GA, Rowlands DD, Zhong S. Internal structure and early thermal evolution of Mars from Mars Global Surveyor topography and gravity. Science 2000; 287:1788-93. [PMID: 10710301 DOI: 10.1126/science.287.5459.1788] [Citation(s) in RCA: 457] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Topography and gravity measured by the Mars Global Surveyor have enabled determination of the global crust and upper mantle structure of Mars. The planet displays two distinct crustal zones that do not correlate globally with the geologic dichotomy: a region of crust that thins progressively from south to north and encompasses much of the southern highlands and Tharsis province and a region of approximately uniform crustal thickness that includes the northern lowlands and Arabia Terra. The strength of the lithosphere beneath the ancient southern highlands suggests that the northern hemisphere was a locus of high heat flow early in martian history. The thickness of the elastic lithosphere increases with time of loading in the northern plains and Tharsis. The northern lowlands contain structures interpreted as large buried channels that are consistent with northward transport of water and sediment to the lowlands before the end of northern hemisphere resurfacing.
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Affiliation(s)
- M T Zuber
- Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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Jolliff BL, Gillis JJ, Haskin LA, Korotev RL, Wieczorek MA. Major lunar crustal terranes: Surface expressions and crust-mantle origins. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999je001103] [Citation(s) in RCA: 585] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Konopliv AS, Binder AB, Hood LL, Kucinskas AB, Sjogren WL, Williams JG. Improved gravity field of the moon from lunar prospector. Science 1998; 281:1476-80. [PMID: 9727968 DOI: 10.1126/science.281.5382.1476] [Citation(s) in RCA: 208] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
An improved gravity model from Doppler tracking of the Lunar Prospector (LP) spacecraft reveals three new large mass concentrations (mascons) on the nearside of the moon beneath the impact basins Mare Humboltianum, Mendel-Ryberg, and Schiller-Zucchius, where the latter basin has no visible mare fill. Although there is no direct measurement of the lunar farside gravity, LP partially resolves four mascons in the large farside basins of Hertzsprung, Coulomb-Sarton, Freundlich-Sharonov, and Mare Moscoviense. The center of each of these basins contains a gravity maximum relative to the surrounding basin. The improved normalized polar moment of inertia (0.3932 +/- 0.0002) is consistent with an iron core with a radius of 220 to 450 kilometers.
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Affiliation(s)
- AS Konopliv
- A. S. Konopliv, A. B. Kucinskas, W. L. Sjogren, J. G. Williams, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA. A. B. Binder, Lunar Research Institute, Gilroy, CA 95020, USA. L. L. Hood, University of Arizona
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