Skip to content

Research at St Andrews

Chronology of martian breccia NWA 7034 and the formation of the martian crustal dichotomy

Research output: Contribution to journalArticle

Author(s)

William S. Cassata, Benjamin E. Cohen, Darren F. Mark, Reto Trappitsch, Carolyn A. Crow, Joshua Wimpenny, Martin R. Lee, Caroline L. Smith

School/Research organisations

Abstract

Martian meteorite Northwest Africa (NWA) 7034 and its paired stones are the only brecciated regolith samples from Mars with compositions that are representative of the average martian crust. These samples therefore provide a unique opportunity to constrain the processes of metamorphism and alteration in the martian crust, which we have investigated via U-Pu/Xe, 40Ar/39Ar, and U-Th-Sm/He chronometry. U-Pu/Xe ages are comparable to previously reported Sm-Nd and U-Pb ages obtained from NWA 7034 and confirm an ancient (>4.3 billion years) age for the source lithology. After almost 3000 million years (Ma) of quiescence, the source terrain experienced several hundred million years of thermal metamorphism recorded by the K-Ar system that appears to have varied both spatially and temporally. Such protracted metamorphism is consistent with plume-related magmatism and suggests that the source terrain covered an areal extent comparable to plume-fed edifices (hundreds of square kilometers). The retention of such expansive, ancient volcanic terrains in the southern highlands over billions of years suggests that formation of the martian crustal dichotomy, a topographic and geophysical divide between the heavily cratered southern highlands and smoother plains of the northern lowlands, likely predates emplacement of the NWA 7034 source terrain—that is, it formed within the first ~100 Ma of planetary formation.

Close

Details

Original languageEnglish
Article numbereaap8306
Number of pages12
JournalScience Advances
Volume4
Issue number5
DOIs
Publication statusPublished - 23 May 2018

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by journal

  1. Manipulating surface magnetic order in iron telluride

    Trainer, C. W. J., Yim, C. M., Heil, C., Giustino, F., Croitori, D., Tsurkan, V., Loidl, A., Rodriguez, E., Stock, C. & Wahl, P., 1 Mar 2019, In : Science Advances. 5, 3, 8 p., eaav3478.

    Research output: Contribution to journalArticle

  2. The comparative genomics and complex population history of Papio baboons

    Rogers, J., Raveendran, M., Harris, R. A., Mailund, T., Leppälä, K., Athanasiadis, G., Schierup, M. H., Cheng, J., Munch, K., Walker, J. A., Konkel, M. K., Jordan, V., Steely, C. J., Beckstrom, T. O., Bergey, C., Burrell, A., Schrempf, D., Noll, A., Kothe, M., Kopp, G. H. & 22 others, Liu, Y., Murali, S., Billis, K., Martin, F. J., Muffato, M., Cox, L., Else, J., Disotell, T., Muzny, D. M., Phillips-conroy, J., Aken, B., Eichler, E. E., Marques-bonet, T., Kosiol, C., Batzer, M. A., Hahn, M. W., Tung, J., Zinner, D., Roos, C., Jolly, C. J., Gibbs, R. A. & Worley, K. C., 30 Jan 2019, In : Science Advances. 5, 1, 15 p., eaau6947.

    Research output: Contribution to journalArticle

  3. Titi monkeys combine alarm calls to create probabilistic meaning

    Berthet, M., Mesbahi, G., Pajot, A., Cäsar, C., Neumann, C. & Zuberbuhler, K., 15 May 2019, In : Science Advances. 5, 5, 10 p., eaav3991.

    Research output: Contribution to journalArticle

  4. A molecular mechanism for the enzymatic methylation of nitrogen atoms within peptide bonds

    Song, H., Van Der Velden, N. S., Shirran, S. L., Bleiziffer, P., Zach, C., Sieber, R., Imani, A. S., Krausbeck, F., Aebi, M., Freeman, M. F., Riniker, S., Künzler, M. & Naismith, J. H., 24 Aug 2018, In : Science Advances. 4, 8, 13 p., eaat2720.

    Research output: Contribution to journalArticle

ID: 253303088

Top