Impact-induced phyllosilicate formation from olivine and water
スポンサーリンク
概要
- 論文の詳細を見る
Shock-recovery experiments on mixtures of olivine and water with gas (air) were performed in a previous study to demonstrate water-mineral interactions during impact events (Furukawa et al., 2007). The products of these former experiments were investigated in the present study using transmission electron microscopy, scanning electron microscopy, and X-ray powder diffraction with the aim of finding evidence of aqueous alteration. Serpentine formed on the surface of shocked olivine with well-developed mosaicism. The yield of serpentine depended on the water/olivine ratio in the starting material, indicating progressive serpentinization under water-rich conditions. Comminution and mosaicism were developed in shocked olivine grains. The temperature and pressure changes of the samples during the experiments were estimated by constructing Hugoniots for mixtures of olivine and water, combined with the results of an additional fracturing experiment on a shocked container. Pressures and temperatures reached 4.6-7.2 GPa and at least 230-390 degrees C, respectively, for 0.7 mu s during in-shock compression. Post-shock temperatures reached a maximum of similar to 1300 degrees C, when the shock wave reached the gas in the sample cavity. The serpentine formed after the post-shock temperature maximum, most likely when temperatures dropped to between 200 and 400 degrees C. This is the first experiment to demonstrate the formation of phyllosilicates using heat supplied by an impact. The present results and estimations suggest that phyllosilicates could form as a result of impacts into oceans as well as by impacts on terrestrial and Martian crustal rocks, and on some asteroidal surfaces, where liquid or solid H(2)O is available. A significant amount of phyllosilicates would have formed during the late heavy bombardment of meteorites on the Hadean Earth, and such phyllosilicates might have affected the prebiotic carbon cycle. (C) 2011 Elsevier Ltd. All rights reserved.
- Pergamonの論文
- 2011-00-00
Pergamon | 論文
- Stereoselective synthesis of a C1-C6 fragment of pinnatoxin A via a 1,4-addition/alkylation sequence
- The Role of Rusts in Corrosion and Corrosion Protection of Iron and Steel
- Combinational recognition of bacterial lipoproteins and peptidoglycan by chicken Toll-like receptor 2 subfamily
- Characterization of char derived from various types of solid wastes from the standpoint of fuel recovery and pretreatment before landfilling
- Fuzzylot : a novel self-organising fuzzy-neural rule-based pilot system for automated vehicles