The thermal state and internal structure of Mars
The thermal state and internal structure of Mars
复制标题
火星的热状态和内部结构
DOI：
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发表时间：
1974
期刊：
影响因子：
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通讯作者：
M. Toksöz
中科院分区：
文献类型：
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作者：
D. H. Johnston;T. McGetchin;M. Toksöz
通过使用理论计算的热历史和密度模型，研究了火星内部的演化和状态。这些模型满足平均密度、惯性矩和水手9号照片所暗示的最近火山活动的约束。Fe-FeS混合物的快速熔化允许在第一个十亿年内形成初始核心。目前，核心半径范围从大约1300到1800 km，这取决于成分，并且即使成分与共晶不同，核心也是液体。硅酸盐的大规模分异发生在最近20亿年。当平均密度为3.96 g/cm ~ 3，半径为3389 km，惯性矩因子为0.377时，密度模型显示地幔密度在3.74 g/cm ~ 3附近较高。因此，FeO含量约为29%，这与低粘度岩浆的产生相一致。火星地幔的化学模型显示，其成分主要是橄榄石，约有56%是镁橄榄石。就进化史而言，火星可能介于月球和地球之间，它的活动高峰期是在过去的10亿年中度过的。
The evolution and state of the interior of Mars are studied through the use of theoretically calculated thermal history and density models. These models satisfy the constraints of mean density, moment of inertia, and recent volcanism implied by the Mariner 9 photographs. Invoking melting of an Fe-FeS mixture permits initial core formation within the first billion years. At the present time the core radius ranges from about 1300 to 1800 km, depending on composition, and the core is liquid even if the composition is varied from the eutectic. Large-scale differentiation of the silicates occurs in the last 2 b.y. When the mean density is 3.96 g/cm3, the radius is 3389 km, and the moment of inertia factor is 0.377, the density models indicate high mantle densities near 3.74 g/cm3. Thus an FeO content of about 29% is implied, consistent with the production of a low-viscosity magma. Chemical models of the Martian mantle indicate a composition primarily of olivine with about 56% forsterite. In terms of evolutionary history, Mars is probably intermediate between the moon and the earth, its peak of activity being passed in the last billion years.