A possible terrestrial analogue for haematite concretions on Mars
A possible terrestrial analogue for haematite concretions on Mars
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DOI：
10.1038/nature02600
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发表时间：
2004-06-17
期刊：
影响因子：
64.8
通讯作者：
Komatsu, G
中科院分区：
文献类型：
--
作者：
Chan, MA;Beitler, B;Komatsu, G
最近的探索揭示了火星浅层地下过去富含水的广泛地质证据。火星探索火星车在子午线平面(1-3)着陆点的大量富含赤铁矿的球体的就地和松散堆积的图像与犹他州南部侏罗纪纳瓦霍砂岩中发现的成岩(沉积后)赤铁矿胶结结核(4，5)惊人地相似。在这里，我们将火星上成像的球形结核与这些陆地结核进行比较，并研究其对类似的地下水相关形成机制的影响。纳瓦霍赤铁矿结核的形态、特征和分布使我们能够推断出在火星上形成类似特征所需的寄主岩石性质和流体过程。我们的结论是，这种球形赤铁矿结核的形成需要有可渗透的主岩、地下水流动和化学反应前沿的存在。
Recent exploration has revealed extensive geological evidence for a water-rich past in the shallow subsurface of Mars. Images of in situ and loose accumulations of abundant, haematite-rich spherical balls from the Mars Exploration Rover 'Opportunity' landing site at Meridiani Planum(1-3) bear a striking resemblance to diagenetic (post-depositional), haematite-cemented concretions found in the Jurassic Navajo Sandstone of southern Utah(4,5). Here we compare the spherical concretions imaged on Mars to these terrestrial concretions, and investigate the implications for analogous groundwater-related formation mechanisms. The morphology, character and distribution of Navajo haematite concretions allow us to infer host-rock properties and fluid processes necessary for similar features to develop on Mars. We conclude that the formation of such spherical haematite concretions requires the presence of a permeable host rock, groundwater flow and a chemical reaction front.