国内动态丨RMDSs揭示月球上哥白尼纪年轻火山作用?
摘要 ●●
Ring Moat Dome Structures (RMDSs) 是月球表面一种低矮的、周围被环形负地形所环绕的穹隆构造,广泛分布于月海玄武岩表面。某些RMDSs与小型撞击坑的相互叠加关系表明月球火山作用可能持续到10亿年以内的哥白尼纪。我们将RMDSs的成因归为两类:年老(30亿年以前)或年轻(0-30亿年之间)。
图1. 一RMDS密集分布区,位于月球正面静海盆地北部。下图为基于2 米分辨率DEM数据的三维显示(LROC NAC影像)。上图分别为一个RMDS的NAC影像、山体阴影图和DEM假彩色影像上的显示结果及提取的RMDS横向剖面图。
图2. 低太阳高度角下的RMDS和撞击坑(LROC NAC影像),该RMDS位于嫦娥4号着陆区-冯卡门撞击坑西南部火山机构上。
图3. 地球上的熔岩冢(Diniega & Németh, 2014):(a)夏威夷岛上陡峭的熔岩冢;(b)塌陷的熔岩冢,阿根廷;(c)残留的熔岩冢,利比亚;(d)尔塔阿雷火山地区(埃塞俄比亚)较新形成的熔岩冢,可看到其顶部沿长轴方向和侧翼的裂缝。
图4. 地球熔岩冢的形成原理(a;Self et al., 1998);玄武质熔岩在地球表面流动过程中的膨胀增生过程和形成的内部三层结构(b-e;Self et al., 1997):上部冷凝壳、中间热层和底部冷凝壳;月球真空和低重力环境下的熔岩在表面流动过程中的冷却过程和分层结构(f);和本研究推导出的RMDS成因理论模型(g;Wilson et al., 2019)。
图5. RMDS与撞击坑的覆盖叠加关系示例,揭示了月球上可能的年轻火山活动。
支持课题
研究结果得到了澳门科技发展基金项目(131/2017/A3)和国家自然科学基金(11903090和11941001)等项目的支持。
参考文献
Anderson, S. W., Smrekar, S. E., & Stofan, E. R. (2012). Tumulus development on lava flows: insights from observations of active tumuli and analysis of formation models. Bulletin of Volcanology, 74(4), 931-946.
Bart, G. D., Nickerson, R. D., Lawder, M. T., & Melosh, H. (2011). Global survey of lunar regolith depths from LROC images. Icarus, 215(2), 485-490.
Basilevsky, A. T. (1976). On the evolution rate of small lunar craters. 7th Lunar and Planetary Science Conference, The Woodlands, TX, 1,005-1,020.
Basilevsky, A. T., Zhang, F., Wöhler, C., Bugiolacchi, R., Head, J. W., & Wilson, L. (2019). Lunar Ring-Moat Dome Structures and Their Relationships with Small Impact Craters. In 50th Lunar and Planetary Science Conference, The Woodlands, TX (abstract #1507).
Borg, L. E., Shearer, C. K., Asmerom, Y., & Papike, J. J. (2004). Prolonged KREEP magmatism on the Moon indicated by the youngest dated lunar igneous rock. Nature, 432(7014), 209-211.
Diniega S., & Németh K. (2014). Tumulus. In: Encyclopedia of Planetary Landforms. Springer, New York, NY, DOI: https://doi.org/10.1007/978-1-4614-9213-9_387-1.
Head, J. W. (1976). Lunar volcanism in space and time. Reviews of Geophysics, 14(2), 265-300.
Head, J. W., & Wilson, L. (2017). Generation, ascent and eruption of magma on the Moon: New insights into source depths, magma supply, intrusions and effusive/explosive eruptions (Part 2: Predicted emplacement processes and observations). Icarus, 283, 176-223.
Hiesinger, H., Head, J. W., Wolf, U., Jaumann, R., & Neukum, G. (2011). Ages and stratigraphy of lunar mare basalts: A synthesis. Recent Advances and Current Research Issues in Lunar Stratigraphy, 477, 1-51.
Hon, K., Kauahikaua, J. I. M., Denlinger, R., & Mackay, K. (1994). Emplacement and inflation of pahoehoe sheet flows: Observations and measurements of active lava flows on Kilauea Volcano, Hawaii. Geological Society of America Bulletin, 106(3), 351-370.
Keszthelyi, L., & Self, S. (1998). Some physical requirements for the emplacement of long basaltic lava flows. Journal of Geophysical Research: Solid Earth, 103(B11), 27,447-27,464.
Khalaf, E. E. D. A. H., & Hammed, M. S. (2016). Morphology and development of pahoehoe flow-lobe tumuli and associated features from a monogenetic basaltic volcanic field, Bahariya Depression, Western Desert, Egypt. Journal of African Earth Sciences, 113, 165-180.
McKay, D. S., Heiken G., Basu A, Blanford G., Simon S., Reedy R., French B.M., & Papike J. (1991). The lunar regolith. In: Lunar Source Book: A User Guide to the Moon. G.H. Heiken, D.T. Vaniman, B.M. French eds., Cambridge University Press, 285-356.
Self, S., Thordarson, T., & Keszthelyi, L. (1997). Emplacement of continental flood basalt lava flows. In: Mahoney, J. J., Coffin, M. F. (Eds.), Large Igneous Provinces: continental, oceanic, and planetary flood volcanism. In: Geophys. Monogr., 100, 381-410.
Self, S., Keszthelyi, L., & Thordarson, T. (1998). The importance of pāhoehoe. Annual Review of Earth and Planetary Sciences, 26(1), 81-110.
Shkuratov, Y. G., & Bondarenko, N. V. (2001). Regolith layer thickness mapping of the Moon by radar and optical data. Icarus, 149(2), 329-338.
Walker, G. P., 1991. Structure, and origin by injection of lava under surface crust, of tumuli,“lava rises”,“lava-rise pits”, and “lava-inflation clefts” in Hawaii. Bulletin of Volcanology, 53(7), 546-558.
Wilson, L., & Head, J. W. (2017a). Eruption of magmatic foams on the Moon: Formation in the waning stages of dike emplacement events as an explanation of “irregular mare patches”. Journal of Volcanology and Geothermal Research 335, 113-127.
Wilson, L., & Head, J. W. (2017b). Generation, ascent and eruption of magma on the Moon: New insights into source depths, magma supply, intrusions and effusive/explosive eruptions (Part 1: Theory). Icarus, 283, 146-175.
Wilson, L., Head, J. W., & Zhang, F. (2019). A theoretical model for the formation of Ring Moat Dome Structures: Products of second boiling in lunar basaltic lava flows. Journal of Volcanology and Geothermal Research, 374, 160-180.
Xiao, Z., & Werner, S. C. (2015). Size‐frequency distribution of crater populations in equilibrium on the Moon, Journal of Geophysical Research: Planets, 120(12), 2,277-2,292.
Zhang, F., Head, J. W., Basilevsky, A. T., Bugiolacchi, R., Komatsu, G., Wilson, L., Fa, W., & Zhu, M. H. (2017). Newly discovered ring-moat dome structures in the lunar maria: Possible origins and implications. Geophysical Research Letters, 44(18), 9,216-9,224.
Zhang, F., Head, J. W., Wöhler, C., Bugiolacchi, R., Wilson, L., Basilevsky, A. T., ... & Zou, Y. L., (2020). Ring‐Moat Dome Structures (RMDSs) in the Lunar Maria: Statistical, Compositional, and Morphological Characterization and Assessment of Theories of Origin. Journal of Geophysical Research: Planets, 125, e2019JE005967.
作者简介:
张锋,助理教授,月球与行星科学国家重点实验室,澳门科技大学。研究方向为行星地质学和比较行星学。
作者:张锋
编辑:李婧
审核:李阳
· 往期推荐 ·
灰岩地层对L群球粒陨石母体裂解绝对年龄的限定
普通球粒陨石中纳米级单质金属铁的辉石分解新成因
一块特殊的陨石记录太阳系早期熔融过程