期刊
GEOCHIMICA ET COSMOCHIMICA ACTA
卷 73, 期 11, 页码 3512-3521出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.gca.2009.03.006
关键词
-
资金
- Science and Technology Facilities Council
- Science and Technology Facilities Council [PP/D002389/1] Funding Source: researchfish
- STFC [PP/D002389/1] Funding Source: UKRI
We have used a recently developed quantitative pyrolysis-Fourier transform infrared spectroscopy method to measure the production of water and carbon dioxide during 250 degrees C desorption and 1000 degrees C gasification steps for a range of carbonaceous chondrites. Greater yields of water and carbon dioxide during gasification are associated with meteorites believed to have experienced more aqueous alteration on their asteroid parent body (i.e. gas yields for petrographic type 1 > type 2 > type 3). Volatile yields most likely reflect quantities of hydrated mineral phases and partially oxidised organic matter. Methane was not detected in the gasification products of the meteorites, allowing an upper limit on its production of around 100 ppm to be calculated based on the sensitivity of the pyrolysis-Fourier transform infrared spectroscopy technique employed. When considered alongside rates of infall of cosmic dust throughout Earth history, the data can be used to evaluate the production of volatiles during the thermal ablation of dust upon atmospheric entry, and to estimate their contribution to a terrestrial planet's atmosphere and hydrosphere. Over the long term, it appears that contributions of this nature to the Earth's volatile inventory are small, although production rates are calculated to have been substantially higher before and during the Late Heavy Bombardment of 3.8-4.0 Ga. Moreover, ablation of carbonaceous chondritic material does not appear to be a plausible source of the atmospheric methane budget of Mars. (C) 2009 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据