Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure
Floor-Fractured Craters (FFCs) are a class of lunar craters characterized by anomalously shallow floors cut by radial, concentric, and/or polygonal fractures; additional interior features are moats, ridges, and patches of mare material. Two formation mechanisms have been hypothesized—floor uplift in...
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| Format: | Article |
| Language: | en_US |
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American Geophysical Union (AGU)
2014
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| Online Access: | http://hdl.handle.net/1721.1/85651 https://orcid.org/0000-0003-2652-8017 |
| _version_ | 1811087514096631808 |
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| author | Jozwiak, Lauren M. Head, James W. Neumann, Gregory A. Zuber, Maria Smith, David Edmund |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Jozwiak, Lauren M. Head, James W. Neumann, Gregory A. Zuber, Maria Smith, David Edmund |
| author_sort | Jozwiak, Lauren M. |
| collection | MIT |
| description | Floor-Fractured Craters (FFCs) are a class of lunar craters characterized by anomalously shallow floors cut by radial, concentric, and/or polygonal fractures; additional interior features are moats, ridges, and patches of mare material. Two formation mechanisms have been hypothesized—floor uplift in response to shallow magmatic intrusion and sill formation, and floor shallowing in response to thermally driven viscous relaxation. This study combines new Lunar Orbiter Laser Altimeter (LOLA) and Lunar Reconnaissance Orbiter Camera (LROC) data to characterize and categorize the population of FFCs and map their distribution on the Moon, and uses variations in floor-fractured crater morphology and regional distribution to investigate the proposed formation mechanisms. The population of FFCs was categorized according to the classes outlined by Schultz (1976). The distribution of these FFC categories shows an evolution of crater morphology from areas adjacent to lunar impact basins to areas in the lunar highlands. We propose that this trend is supportive of formation by shallow magmatic intrusion and sill formation—crustal thickness determines the magnitude of magmatic driving pressure, and thus either piston-like floor uplift for high magnitude, or a convex floor profile for low magnitude. Predictions from previous studies modeling viscous relaxation are inconsistent with the observed altimetric profiles of FFCs. Hence our analysis favors FFC formation by shallow magmatic intrusion, with the variety of FFC morphologies being intimately linked with location and crustal thickness, and the driving pressure of the intrusion. Data from the GRAIL (Gravity Recovery and Interior Laboratory) mission will help to test these conclusions. |
| first_indexed | 2024-09-23T13:47:18Z |
| format | Article |
| id | mit-1721.1/85651 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T13:47:18Z |
| publishDate | 2014 |
| publisher | American Geophysical Union (AGU) |
| record_format | dspace |
| spelling | mit-1721.1/856512022-10-01T17:09:18Z Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure Jozwiak, Lauren M. Head, James W. Neumann, Gregory A. Zuber, Maria Smith, David Edmund Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Zuber, Maria Smith, David Edmund Floor-Fractured Craters (FFCs) are a class of lunar craters characterized by anomalously shallow floors cut by radial, concentric, and/or polygonal fractures; additional interior features are moats, ridges, and patches of mare material. Two formation mechanisms have been hypothesized—floor uplift in response to shallow magmatic intrusion and sill formation, and floor shallowing in response to thermally driven viscous relaxation. This study combines new Lunar Orbiter Laser Altimeter (LOLA) and Lunar Reconnaissance Orbiter Camera (LROC) data to characterize and categorize the population of FFCs and map their distribution on the Moon, and uses variations in floor-fractured crater morphology and regional distribution to investigate the proposed formation mechanisms. The population of FFCs was categorized according to the classes outlined by Schultz (1976). The distribution of these FFC categories shows an evolution of crater morphology from areas adjacent to lunar impact basins to areas in the lunar highlands. We propose that this trend is supportive of formation by shallow magmatic intrusion and sill formation—crustal thickness determines the magnitude of magmatic driving pressure, and thus either piston-like floor uplift for high magnitude, or a convex floor profile for low magnitude. Predictions from previous studies modeling viscous relaxation are inconsistent with the observed altimetric profiles of FFCs. Hence our analysis favors FFC formation by shallow magmatic intrusion, with the variety of FFC morphologies being intimately linked with location and crustal thickness, and the driving pressure of the intrusion. Data from the GRAIL (Gravity Recovery and Interior Laboratory) mission will help to test these conclusions. 2014-03-14T19:24:51Z 2014-03-14T19:24:51Z 2012-11 2012-09 Article http://purl.org/eprint/type/JournalArticle 0148-0227 http://hdl.handle.net/1721.1/85651 Jozwiak, Lauren M., James W. Head, Maria T. Zuber, David E. Smith, and Gregory A. Neumann. “Lunar Floor-Fractured Craters: Classification, Distribution, Origin and Implications for Magmatism and Shallow Crustal Structure.” Journal of Geophysical Research 117, no. E11 (2012). Copyright © 2012 American Geophysical Union https://orcid.org/0000-0003-2652-8017 en_US http://dx.doi.org/10.1029/2012je004134 Journal of Geophysical Research Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Geophysical Union (AGU) MIT web domain |
| spellingShingle | Jozwiak, Lauren M. Head, James W. Neumann, Gregory A. Zuber, Maria Smith, David Edmund Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure |
| title | Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure |
| title_full | Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure |
| title_fullStr | Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure |
| title_full_unstemmed | Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure |
| title_short | Lunar floor-fractured craters: Classification, distribution, origin and implications for magmatism and shallow crustal structure |
| title_sort | lunar floor fractured craters classification distribution origin and implications for magmatism and shallow crustal structure |
| url | http://hdl.handle.net/1721.1/85651 https://orcid.org/0000-0003-2652-8017 |
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