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Organic Material in Micrometeorites: Processes Affecting Its Delivery to Planetary Environments Open Research Online The Open University’s repository of research publications and other research outputs Organic Material in Micrometeorites: Processes Affecting Its Delivery to Planetary Environments Thesis How to cite: Wilson, Rebecca (2010). Organic Material in Micrometeorites: Processes Affecting Its Delivery to Planetary Environments. PhD thesis The Open University. For guidance on citations see FAQs. c 2010 The Author https://creativecommons.org/licenses/by-nc-nd/4.0/ Version: Version of Record Link(s) to article on publisher’s website: http://dx.doi.org/doi:10.21954/ou.ro.0000f233 Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online’s data policy on reuse of materials please consult the policies page. oro.open.ac.uk The Open The UniversityOpen Organic Material in Micrometeorites: Processes Affecting its Delivery to Planetary Environments Rebecca Wilson M.Sci. (Hons) ARSM (Imperial College London) 2004 Submitted for the degree of Doctor of Philosophy Faculty of Science, The Open University Supervised by: Dr. Ian Franchi, Dr. Iain Gilmour, Dr. Victoria Pearson and Prof. Ian Wright Submitted June 2009 rN.ATC: o£ SoBmiSSiOA - ZooR Ci'PCVfc O 2 2—0\O ProQuest Number: 13837661 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a com plete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. uest ProQuest 13837661 Published by ProQuest LLC(2019). Copyright of the Dissertation is held by the Author. All rights reserved. This work is protected against unauthorized copying under Title 17, United States C ode Microform Edition © ProQuest LLC. ProQuest LLC. 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106- 1346 Abstract During their delivery to Earth, extraterrestrial dust particles (EDPs) are heated via aerodynamic braking in the upper atmosphere, liberating volatile and organic species. This study investigates the influence of atmospheric entry heating on this liberation process from Murchison (an EDP analogue), in order to assess the EDP contribution of biologically significant material to the early Earth. Experimental simulations used a filament pulse pyrolyser to flash heat Murchison, replicating early Earth EDP atmospheric entry conditions. These simulations determined that the dehydration of phyllosilicates, the decomposition of organic and carbonate materials released H 20, organic carbon and C 02, respectively. Further characterisation of the released organic species (using GCxGC-TOFMS) identified a range of aliphatic, aromatic, PAH, O-bearing, S-bearing and N-bearing species; including biomolecule precursors. Relative abundances of these organic species were dependant not only on simulation peak temperature and duration, but also on their reaction with other fragments, which may have led to their production as secondary products. In a complimentary study, comprehensive volatile organic analysis of Antarctic micrometeorites (AMMs) identified a range of aromatic, aliphatic, N-bearing, S-bearing, S- N-bearing and O-bearing species. Variations in the distribution of AMM aromatic species in comparison to the EDP analogue (as used in simulations) are consistent with i) the liberation of species during atmospheric entry heating ii) the alteration of organic material during Antarctic weathering processes and iii) a contribution from terrestrial sources. Alternatively, these deviations could reflect a different source (parent body) composition. This investigation demonstrates that the abundance and composition of volatile and organic species liberated and retained in EDPs during entry heating (and their subsequent atmospheric reactions), may have played a role in atmospheric and climate development. EDPs additionally served as a source of prebiotic molecules and may have provided sites for chemical evolution. Acknowledgements I would like to thank my supervisors Ian Franchi, lain Gilmour, Vic Pearson and Ian Wright for their continued efforts, advice and expertise over the past four years as this project has evolved. Most notably Vic, who has helped me keep the goal in sight! My thanks to Steve Sestak, for his knowledge of thermocouples; Mabs Gilmour and Jenny Gibson, for their help using the ANCA; and Diane Turner for her comprehensive training and troubleshooting in GCxGC-TOFMS - without which I would have been lost! I would like to acknowledge Jean Duprat, Celcile Engrand and Michelle Maurrete at CSNSM CNRS-University Paris Sud for providing me with Antarctic micrometeorite and terrestrial samples from the Cap-Prudhomme site, and Elena Dobrica for her scanning electron microscope analyses of the particles. I will be forever grateful for Bungie Studios and their development of Halo, Halo 2 and Halo 3, which provided me with a great source of stress relief throughout my Ph.D.! Finally, I would like to thank Oily, my parents and my sister for their continued financial and emotional support throughout my university years. Without their personal sacrifices, realisation of my Ph.D. would not have been possible. 7 <t> e-Q[DQ 5 -? § Q .U O PHa Q 3 S'110 dust § osfecntry * H Tl '0 2. matter . •*. , □ S (o terrestrial cr. Murchison-H R v/j 1 • experimental contain I?) ^^ P f a* k tO volatl|. iq » a imacromoiecuiar |g liheatimq^ L u n a r surface nature } C / ro atmosphemc^i Meteorites ^ (/)4P lb W?3materiaiT5!Q g * alk yl release q ^ o— Simulation/r\|3 .w | ^>ar^?orom adro^atic0 ntirV 3:ftO «x ^ ... £ presenting v JaO a" o »3 lM5n § 1 N r-r (9CO decomposition ? - -y ^ CO 1 ra 32 A A A A A ~ 8 £3 V V C/1 average J““M I II I W j$ A study Permian rTQC/i secondary O D -^ * conditions gAntarctic T QD 5-pyrolysis 3 o r p la n e ta ry 3 Acta may, T3X OQusingalso d"'” ? ? d early w c£-rtn higher | w ith in Iq Q | 1 p w § alteration c t q D □ 5 - C J /-‘r—{/) J s 3 g origin , C = g " Q 1 abundance*- — * total V < I (/) (a § aliphatic j/J'relative^ ^ | | science! x -s 3 nitrogen l||Earth * tf> ;y<9r - c r mineralogy 2 3 Contents ABSTRACT.................................................................................................................................................................... ii ACKNOWLEDGEMENTS............................................................................................................................................. Hi WORDLE...................................................................................................................................................................... iv TABLE OF CONTENTS...................................................................................................................................................v LIST OF FIGURES....................................................................................................................................................... viii LIST OF TABLES............................................................................................................................................................ xi 1. INTRODUCTION.....................................................................................................................................1 1 .1 . C lassification of M e t e o r it e s ................................................................................................................................ 2 1.1.1. Chondrites.............................................................................................. 4 1.1.2. Carbonaceous Chondrites.....................................................................................................................................6 1.2. Carbon in Carbonaceous chondrites ................................................................................................................ 7 1.2.1. The Extractable Organic Fraction in Carbonaceous Chondrites ....................................................7 1.2.2. Insoluble Organic Matter in Carbonaceous Chondrites .................................................................. 12 1.2.3. The Origin o f Meteoritic Organic M aterial ..............................................................................................14 1.3. Extraterrestrial Dust Particles ........................................................................................................................1 6 1.3.1. The Classification o f Micrometeorites ........................................................................................................16 1.3.2. The Classification o f Interplanetary Dust Particles ............................................................................ 21 1.3.3. Summary ofIDP Classification ....................................................................................................................... 24 1 .4 . Extraterrestrial D u st Particle C h e m is t r y .................................................................................................. 2 4 1.4.1. Elemental Abundances ofM M s .....................................................................................................................24 1.4.2. Elemental Abundances o f Interplanetary Dust Particles .................................................................25 1.4.3. Carbon in Extraterrestrial Dust Particles .................................................................................................
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