Department of Geology and Geophysics, Louisiana State University, Louisiana, USA.
Department of Oceanography and Marine Geology, Faculty of Fisheries and Marine Sciences &Technology, University of Rahuna, Matara, Sri Lanka.
Sci Rep. 2017 Feb 24;7:43177. doi: 10.1038/srep43177.
A major knowledge gap exists on how eruptive compositions of a single martian volcanic province change over time. Here we seek to fill that gap by assessing the compositional evolution of Elysium, a major martian volcanic province. A unique geochemical signature overlaps with the southeastern flows of this volcano, which provides the context for this study of variability of martian magmatism. The southeastern lava fields of Elysium Planitia show distinct chemistry in the shallow subsurface (down to several decimeters) relative to the rest of the martian mid-to-low latitudes (average crust) and flows in northwest Elysium. By impact crater counting chronology we estimated the age of the southeastern province to be 0.85 ± 0.08 Ga younger than the northwestern fields. This study of the geochemical and temporal differences between the NW and SE Elysium lava fields is the first to demonstrate compositional variation within a single volcanic province on Mars. We interpret the geochemical and temporal differences between the SE and NW lava fields to be consistent with primary magmatic processes, such as mantle heterogeneity or change in depth of melt formation within the martian mantle due to crustal loading.
关于单个火星火山省的喷发成分随时间如何变化，存在一个主要的知识空白。在这里，我们通过评估埃律西昂火山这个主要的火星火山省的成分演化来填补这一空白。该火山的东南熔岩流与一个独特的地球化学特征重叠，为这项关于火星岩浆活动可变性的研究提供了背景。与火星中低纬度地区（平均地壳）的其余部分和西北埃律西昂的熔岩流相比，埃律西昂平原东南熔岩场在浅层地下（至数分米）的化学成分明显不同。通过撞击坑计数年代学，我们估计东南省的年龄比西北流场年轻 0.85 ± 0.08 Ga。这项对西北和东南埃律西昂熔岩场的地球化学和时间差异的研究首次证明了火星单个火山省内的成分变化。我们将东南和西北熔岩场之间的地球化学和时间差异解释为与主要岩浆过程一致，例如地幔不均一性或由于地壳负荷导致火星地幔中熔融形成深度的变化。
