气候变化领域集成服务门户(CCPortal): Critically testing olivine-hosted putative martian biosignatures in the Yamato 000593 meteorite

CCPortal

DOI	10.1111/gbi.12361
	Critically testing olivine-hosted putative martian biosignatures in the Yamato 000593 meteorite—Geobiological implications
	McLoughlin N.; Grosch E.G.; Vullum P.E.; Guagliardo P.; Saunders M.; Wacey D.
发表日期	2019
ISSN	14724677
起始页码	691
结束页码	707
卷号	17 期号:6
英文摘要	On rocky planets such as Earth and Mars the serpentinization of olivine in ultramafic crust produces hydrogen that can act as a potential energy source for life. Direct evidence of fluid–rock interaction on Mars comes from iddingsite alteration veins found in martian meteorites. In the Yamato 000593 meteorite, putative biosignatures have been reported from altered olivines in the form of microtextures and associated organic material that have been compared to tubular bioalteration textures found in terrestrial sub-seafloor volcanic rocks. Here, we use a suite of correlative, high-sensitivity, in situ chemical, and morphological analyses to characterize and re-evaluate these microalteration textures in Yamato 000593, a clinopyroxenite from the shallow subsurface of Mars. We show that the altered olivine crystals have angular and micro-brecciated margins and are also highly strained due to impact-induced fracturing. The shape of the olivine microalteration textures is in no way comparable to microtunnels of inferred biological origin found in terrestrial volcanic glasses and dunites, and rather we argue that the Yamato 000593 microtextures are abiotic in origin. Vein filling iddingsite extends into the olivine microalteration textures and contains amorphous organic carbon occurring as bands and sub-spherical concentrations <300 nm across. We propose that a martian impact event produced the micro-brecciated olivine crystal margins that reacted with subsurface hydrothermal fluids to form iddingsite containing organic carbon derived from abiotic sources. These new data have implications for how we might seek potential biosignatures in ultramafic rocks and impact craters on both Mars and Earth. © 2019 John Wiley & Sons Ltd
关键词	crater crystal structure Earth fluid-structure interaction fracture hydrothermal fluid Mars Martian atmosphere meteorite olivine seafloor serpentinization testing method ultramafic rock volcanic rock iron derivative magnesium derivative olivine silicate astrobiology astronomy chemistry space Exobiology Extraterrestrial Environment Iron Compounds Magnesium Compounds Mars Meteoroids Silicates
语种	英语
来源机构	Geobiology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/133219
推荐引用方式 GB/T 7714	McLoughlin N.,Grosch E.G.,Vullum P.E.,等. Critically testing olivine-hosted putative martian biosignatures in the Yamato 000593 meteorite—Geobiological implications[J]. Geobiology,2019,17(6).
APA	McLoughlin N.,Grosch E.G.,Vullum P.E.,Guagliardo P.,Saunders M.,&Wacey D..(2019).Critically testing olivine-hosted putative martian biosignatures in the Yamato 000593 meteorite—Geobiological implications.,17(6).
MLA	McLoughlin N.,et al."Critically testing olivine-hosted putative martian biosignatures in the Yamato 000593 meteorite—Geobiological implications".17.6(2019).