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Olivine and Pyroxene from the Mantle of Asteroid 4 Vesta ∗ Nicole G
Earth and Planetary Science Letters 418 (2015) 126–135 Contents lists available at ScienceDirect Earth and Planetary Science Letters www.elsevier.com/locate/epsl Olivine and pyroxene from the mantle of asteroid 4 Vesta ∗ Nicole G. Lunning a, , Harry Y. McSween Jr. a,1, Travis J. Tenner b,2, Noriko T. Kita b,3, Robert J. Bodnar c,4 a Department of Earth and Planetary Sciences and Planetary Geosciences Institute, University of Tennessee, Knoxville, TN 37996, USA b Department of Geosciences, University of Wisconsin, Madison, WI 53706, USA c Department of Geosciences, Virginia Tech, Blacksburg, VA 24061, USA a r t i c l e i n f o a b s t r a c t Article history: A number of meteorites contain evidence that rocky bodies formed and differentiated early in our solar Received 25 September 2014 system’s history, and similar bodies likely contributed material to form the planets. These differentiated Received in revised form 25 February 2015 rocky bodies are expected to have mantles dominated by Mg-rich olivine, but direct evidence for such Accepted 25 February 2015 mantles beyond our own planet has been elusive. Here, we identify olivine fragments (Mg# = 80–92) in Available online 17 March 2015 howardite meteorites. These Mg-rich olivine fragments do not correspond to an established lithology Editor: T. Mather in the howardite–eucrite–diogenite (HED) meteorites, which are thought to be from the asteroid 4 Keywords: Vesta; their occurrence in howardite breccias, combined with diagnostic oxygen three-isotope signatures planetary formation and minor element chemistry, indicates they are vestan. -
Assessment of the Mesosiderite-Diogenite Connection and an Impact Model for the Genesis of Mesosiderites
45th Lunar and Planetary Science Conference (2014) 2554.pdf ASSESSMENT OF THE MESOSIDERITE-DIOGENITE CONNECTION AND AN IMPACT MODEL FOR THE GENESIS OF MESOSIDERITES. T. E. Bunch1,3, A. J. Irving2,3, P. H. Schultz4, J. H. Wittke1, S. M. Ku- ehner2, J. I. Goldstein5 and P. P. Sipiera3,6 1Dept. of Geology, SESES, Northern Arizona University, Flagstaff, AZ 86011 ([email protected]), 2Dept. of Earth & Space Sciences, University of Washington, Seattle, WA, 3Planetary Studies Foundation, Galena, IL, 4Dept. of Geological Sciences, Brown University, Providence, RI, 5Dept. of Geolo- gy, University of Massachusetts, Amherts, MA, 6Field Museum of Natural History, Chicago, IL. Introduction: Among well-recognized meteorite 34) is the most abundant silicate mineral and in some classes, the mesosiderites are perhaps the most com- clasts contains inclusions of FeS, tetrataenite, merrillite plex and petrogenetically least understood. Previous and silica. Three of the ten norite clasts contain a few workers have contributed important information about tiny grains of olivine (Fa24-32). A single, fine-grained “classic” falls and Antarctic finds, and have proposed breccia clast was found in NWA 5312 (see Figure 2). several different models for mesosiderite genesis [1]. Unlike the case of pallasites, the co-occurrence of met- al and silicates (predominantly orthopyroxene and cal- cic plagioclase) in mesosiderites is inconsistent with a single-stage “igneous” history, and instead seems to demand admixture of at least two separate compo- nents. Here we review the models in light of detailed ex- amination of multiple specimens from a very large mesosiderite strewnfield in Northwest Africa. Many specimens (totaling at least 80 kilograms) from this area (probably in Algeria) have been classified sepa- rately by us and others; however, in most cases the Figure 1. -
Metal-Silicate Fractionation and Chondrule Formation
A756 Goldschmidt 2004, Copenhagen 6.3.12 6.3.13 Metal-silicate fractionation and Fe isotopes fractionation in chondrule formation: Fe isotope experimental chondrules 1 2 2,3 constraints S. LEVASSEUR , B. A. COHEN , B. ZANDA , 2 1 1 1 1 2 2 R.H. HEWINS AND A.N. HALLIDAY X.K. ZHU , Y. GUO , S.H. TANG , A. GALY , R.D. ASH 2 AND R.K O’NIONS 1 ETHZ, Dep. of Earth Sciences, Zürich, Switzerland ([email protected]) 1 Lab of Isotope Geology, MLR, Chinese Academy of 2 Rutgers University, Piscataway, NJ, USA Geological Sciences, 26Baiwanzhuang Road, Beijing, 3 Muséum National d’Histoire Naturelle, Paris, France China ([email protected]) 2 Department of Earth Sciences, Oxford University, Parks Road, Oxford, OX1 3PR, UK Natural chondrules show an Fe-isotopic mass fractionation range of a few δ-units [1,2] that is interpreted either as the result of Fe depletion from metal-silicate Recent studies have shown that considerable variations of fractionation during chondrule formation [1] or as the Fe isotopes exist in both meteoritic and terrestrial materials, reflection of the fractionation range of chondrule precursors and that they are related, through mass-dependent [2]. In order to better understand the iron isotopic fractionation, to a single isotopically homogeneous source[1]. compositions of chondrules we conducted experiments to This implies that the Fe isotope variations recorded in the study the effects of reduction and evaporation of iron on iron solar system materials must have resulted from mass isotope systematics. fractionation incurred by the processes within the solar system About 80mg of powdered slag fayalite was placed in a itself. -
Australian Aborigines and Meteorites
Records of the Western Australian Museum 18: 93-101 (1996). Australian Aborigines and meteorites A.W.R. Bevan! and P. Bindon2 1Department of Earth and Planetary Sciences, 2 Department of Anthropology, Western Australian Museum, Francis Street, Perth, Western Australia 6000 Abstract - Numerous mythological references to meteoritic events by Aboriginal people in Australia contrast with the scant physical evidence of their interaction with meteoritic materials. Possible reasons for this are the unsuitability of some meteorites for tool making and the apparent inability of early Aborigines to work metallic materials. However, there is a strong possibility that Aborigines witnessed one or more of the several recent « 5000 yrs BP) meteorite impact events in Australia. Evidence for Aboriginal use of meteorites and the recognition of meteoritic events is critically evaluated. INTRODUCTION Australia, although for climatic and physiographic The ceremonial and practical significance of reasons they are rarely found in tropical Australia. Australian tektites (australites) in Aboriginal life is The history of the recovery of meteorites in extensively documented (Baker 1957 and Australia has been reviewed by Bevan (1992). references therein; Edwards 1966). However, Within the continent there are two significant areas despite abundant evidence throughout the world for the recovery of meteorites: the Nullarbor that many other ancient civilizations recognised, Region, and the area around the Menindee Lakes utilized and even revered meteorites (particularly of western New South Wales. These accumulations meteoritic iron) (e.g., see Buchwald 1975 and have resulted from prolonged aridity that has references therein), there is very little physical or allowed the preservation of meteorites for documentary evidence of Aboriginal acknowledge thousands of years after their fall, and the large ment or use of meteoritic materials. -
Meteorite Dunite Breccia Mil 03443: a Probable Crustal Cumulate Closely Related to Diogenites from the Hed Parent Asteroid
METEORITE DUNITE BRECCIA MIL 03443: A PROBABLE CRUSTAL CUMULATE CLOSELY RELATED TO DIOGENITES FROM THE HED PARENT ASTEROID. David W Mittlefehldt, Astromateri- als Research Office, NASA/Johnson Space Center, Houston, Texas, USA, ([email protected]). Introduction: There are numerous types of differ- Metal is very rare, and occurs as grains a few microns entiated meteorites, but most represent either the crusts in size associated with troilite. or cores of their parent asteroids. Ureilites, olivine- pyroxene-graphite rocks, are exceptions; they are man- tle restites [1]. Dunite is expected to be a common mantle lithology in differentiated asteroids. In particu- lar, models of the eucrite parent asteroid contain large volumes of dunite mantle [2-4]. Yet dunites are very rare among meteorites, and none are known associated with the howardite, eucrite, diogenite (HED) suite. Spectroscopic measurements of 4 Vesta, the probable HED parent asteroid, show one region with an olivine signature [5] although the surface is dominated by ba- saltic and orthopyroxenitic material equated with eucrites and diogenites [6]. One might expect that a small number of dunitic or olivine-rich meteorites might be delivered along with the HED suite. The 46 gram meteoritic dunite MIL 03443 (Fig. 1) Figure 2. BSE image of MIL 03443 showing its gen- was recovered from the Miller Range ice field of Ant- eral fragmental breccia texture, and primary texture arctica. This meteorite was tentatively classified as a between olivine, orthopyroxene and chromite. mesosiderite because large, dunitic clasts are found in this type of meteorite, but it was noted that MIL 03443 could represent a dunite sample of the HED suite [7]. -
Magnetite Biomineralization and Ancient Life on Mars Richard B Frankel* and Peter R Buseckt
Magnetite biomineralization and ancient life on Mars Richard B Frankel* and Peter R Buseckt Certain chemical and mineral features of the Martian meteorite with a mass distribution unlike terrestrial PAHs or those from ALH84001 were reported in 1996 to be probable evidence of other meteorites; thirdly, bacterium-shaped objects (BSOs) ancient life on Mars. In spite of new observations and up to several hundred nanometers long that resemble fos interpretations, the question of ancient life on Mars remains silized terrestrial microorganisms; and lastly, 10-100 nm unresolved. Putative biogenic, nanometer magnetite has now magnetite (Fe304), pyrrhotite (Fel_xS), and greigite (Fe3S4) become a leading focus in the debate. crystals. These minerals were cited as evidence because of their similarity to biogenic magnetic minerals in terrestrial Addresses magnetotactic bacteria. *Department of Physics, California Polytechnic State University, San Luis Obispo, California 93407, USA; e-mail: [email protected] The ancient life on Mars hypothesis has been extensively tDepartments of Geology and Chemistry/Biochemistry, Arizona State challenged, and alternative non-biological processes have University, Tempe, Arizona 85287-1404, USA; e-mail: [email protected] been proposed for each of the four features cited by McKay et al. [4]. In this paper we review the current situa tion regarding their proposed evidence, focusing on the Abbreviations putative biogenic magnetite crystals. BCM biologically controlled mineralization BIM biologically induced mineralization BSO bacterium-shaped object Evidence for and against ancient Martian life PAH polycyclic aromatic hydrocarbon PAHs and BSOs Reports of contamination by terrestrial organic materials [5°,6°] and the similarity of ALH84001 PAHs to non-bio genic PAHs in carbonaceous chondrites [7,8] make it Introduction difficult to positively identify PAHs of non-terrestrial, bio A 2 kg carbonaceous stony meteorite, designated genic origin. -
Lost Lake by Robert Verish
Meteorite-Times Magazine Contents by Editor Like Sign Up to see what your friends like. Featured Monthly Articles Accretion Desk by Martin Horejsi Jim’s Fragments by Jim Tobin Meteorite Market Trends by Michael Blood Bob’s Findings by Robert Verish IMCA Insights by The IMCA Team Micro Visions by John Kashuba Galactic Lore by Mike Gilmer Meteorite Calendar by Anne Black Meteorite of the Month by Michael Johnson Tektite of the Month by Editor Terms Of Use Materials contained in and linked to from this website do not necessarily reflect the views or opinions of The Meteorite Exchange, Inc., nor those of any person connected therewith. In no event shall The Meteorite Exchange, Inc. be responsible for, nor liable for, exposure to any such material in any form by any person or persons, whether written, graphic, audio or otherwise, presented on this or by any other website, web page or other cyber location linked to from this website. The Meteorite Exchange, Inc. does not endorse, edit nor hold any copyright interest in any material found on any website, web page or other cyber location linked to from this website. The Meteorite Exchange, Inc. shall not be held liable for any misinformation by any author, dealer and or seller. In no event will The Meteorite Exchange, Inc. be liable for any damages, including any loss of profits, lost savings, or any other commercial damage, including but not limited to special, consequential, or other damages arising out of this service. © Copyright 2002–2010 The Meteorite Exchange, Inc. All rights reserved. No reproduction of copyrighted material is allowed by any means without prior written permission of the copyright owner. -
Howardite-Eucrite-Diogenite) Title PARENT BODY -PARTIAL MELT EXPERIMENTS on DIFFERENTIATION PROCESSES-( Dissertation 全文 )
EVOLUTION OF THE HED (Howardite-Eucrite-Diogenite) Title PARENT BODY -PARTIAL MELT EXPERIMENTS ON DIFFERENTIATION PROCESSES-( Dissertation_全文 ) Author(s) Isobe, Hiroshi Citation Kyoto University (京都大学) Issue Date 1991-03-23 URL http://dx.doi.org/10.11501/3053044 Right Type Thesis or Dissertation Textversion author Kyoto University 学位 申請論文 磯部博志 EVOLUTION OF THE HED (howardite-eucrite-diogenite) PARENT BODY -PARTIAL MELT EXPERIMENTS ON DIFFERENTIATION PROCESSES- Hiroshi ISOBE Department of Environmental Safety Research Japan Atomic Energy Research Institute Tokai, Ibaraki, 319-11, JAPAN CONTENTS Abstract 1 Introduction1 2 Experiments —starting materials and procedures13 2-1 Composition of the starting materials13 2-2 Experimental procedures19 3 Results and interpretation25 3-1 Mineral assemblages of the run products25 3-2 Composition of the melts and minerals34 4 Discussion60 4-1 Melting relations on the 'pseudo-liquidus' diagrams 60 4-2 Fractionation sequence71 4-3 Physical conditions of the solid-liquid separations 78 4-4 Summary of the present evolution model of HEDP-PB96 Acknowledgments98 References99 Appendix 1 Chemistry of HED and pallasite meteorites106 Appendix 2 Tables of compositions of run products116 Abstract Three series of melting experiments with a chondritic material, a eucrite-diogenite mixture, and a eucritic material were carried out using a one atmosphere gas mixing furnace to illustrate liquidus phase relation and chemical compositions of the phases. Locations of an olivine control line, olivine-pyroxene phase boundary -
Radar-Enabled Recovery of the Sutter's Mill Meteorite, A
RESEARCH ARTICLES the area (2). One meteorite fell at Sutter’sMill (SM), the gold discovery site that initiated the California Gold Rush. Two months after the fall, Radar-Enabled Recovery of the Sutter’s SM find numbers were assigned to the 77 me- teorites listed in table S3 (3), with a total mass of 943 g. The biggest meteorite is 205 g. Mill Meteorite, a Carbonaceous This is a tiny fraction of the pre-atmospheric mass, based on the kinetic energy derived from Chondrite Regolith Breccia infrasound records. Eyewitnesses reported hearing aloudboomfollowedbyadeeprumble.Infra- Peter Jenniskens,1,2* Marc D. Fries,3 Qing-Zhu Yin,4 Michael Zolensky,5 Alexander N. Krot,6 sound signals (table S2A) at stations I57US and 2 2 7 8 8,9 Scott A. Sandford, Derek Sears, Robert Beauford, Denton S. Ebel, Jon M. Friedrich, I56US of the International Monitoring System 6 4 4 10 Kazuhide Nagashima, Josh Wimpenny, Akane Yamakawa, Kunihiko Nishiizumi, (4), located ~770 and ~1080 km from the source, 11 12 10 13 Yasunori Hamajima, Marc W. Caffee, Kees C. Welten, Matthias Laubenstein, are consistent with stratospherically ducted ar- 14,15 14 14,15 16 Andrew M. Davis, Steven B. Simon, Philipp R. Heck, Edward D. Young, rivals (5). The combined average periods of all 17 18 18 19 20 Issaku E. Kohl, Mark H. Thiemens, Morgan H. Nunn, Takashi Mikouchi, Kenji Hagiya, phase-aligned stacked waveforms at each station 21 22 22 22 23 Kazumasa Ohsumi, Thomas A. Cahill, Jonathan A. Lawton, David Barnes, Andrew Steele, of 7.6 s correspond to a mean source energy of 24 4 24 2 25 Pierre Rochette, Kenneth L. -
Carbonaceous Chondrite-Rich Howardites; the Potential for Hydrous Lithologies on the Hed Parent
CARBONACEOUS CHONDRITE-RICH HOWARDITES; THE POTENTIAL FOR HYDROUS LITHOLOGIES ON THE HED PARENT. J. S. Herrin 1,2 , M. E. Zolensky 2, J. A. Cartwright 3, D. W. Mittle- fehldt 2, and D. K. Ross 1,2 . 1ESCG Astromaterials Research Group, Houston, Texas, USA ( [email protected] ), 2NASA Johnson Space Center, Houston, Texas, USA, 3Max Planck Institut für Chemie, Mainz, Germany. Introduction: Howardites, eucrites, and dioge- clasts texturally resembling CM2 up to 7mm occupy- nites, collectively referred to as the “HED’s”, are a ing nearly half of the sample area accompanied 1-5 clan of meteorites thought to represent three different mm subangular impact melt clasts containing relict lithologies from a common parent body. Collectively eucritic fragments. The remaining medium and fine they are the most abundant type of achondrites in terre- fraction of the specimen consists of mm-to-sub-mm strial collections [1]. Eucrites are crustal basalts and angular-to-subrounded eucritic, diogenitic, carbona- gabbros, diogenites are mostly orthopyroxenites and ceous chondrite clasts set in a medium-to-coarse angu- are taken to represent lower crust or upper mantle ma- lar matrix of same materials. The eucrite/diogenite terials, and howardites are mixed breccias containing ratio of identifiable clasts is approximately 50/50. The both lithologies and are generally regarded as derived total modal abundance of visible carbonaceous chon- from the regolith or near-surface. drite fragments is ~60%. The presence of exogenous chondritic material in PRA 04402 is a howardite breccia consisting of howardite breccias has long been recognized [2,3]. As mm-to-sub-mm subrounded-to-subangular diogenite a group, howardites exhibit divergence in bulk chemi- and eucritic clasts in roughly equal proportions set in a stry from what would be produced by mixing of dioge- medium-to-coarse matrix. -
Aqueous Alteration in Martian Meteorites: Comparing Mineral Relations in Igneous-Rock Weathering of Martian Meteorites and in the Sedimentary Cycle of Mars
AQUEOUS ALTERATION IN MARTIAN METEORITES: COMPARING MINERAL RELATIONS IN IGNEOUS-ROCK WEATHERING OF MARTIAN METEORITES AND IN THE SEDIMENTARY CYCLE OF MARS MICHAEL A. VELBEL Department of Geological Sciences, 206 Natural Science Building, Michigan State University, East Lansing, Michigan 48824-1115 USA e-mail: [email protected] ABSTRACT: Many of the minerals observed or inferred to occur in the sediments and sedimentary rocks of Mars, from a variety of Mars-mission spacecraft data, also occur in Martian meteorites. Even Martian meteorites recovered after some exposure to terrestrial weathering can preserve preterrestrial evaporite minerals and useful information about aqueous alteration on Mars, but the textures and textural contexts of such minerals must be examined carefully to distinguish preterrestrial evaporite minerals from occurrences of similar minerals redistributed or formed by terrestrial processes. Textural analysis using terrestrial microscopy provides strong and compelling evidence for preterrestrial aqueous alteration products in a numberof Martian meteorites. Occurrences of corroded primary rock-forming minerals and alteration products in meteorites from Mars cover a range of ages of mineral–water interaction, from ca. 3.9 Ga (approximately mid-Noachian), through one or more episodes after ca. 1.3 Ga (approximately mid–late Amazonian), through the last half billion years (late Amazonian alteration in young shergottites), to quite recent. These occurrences record broadly similar aqueous corrosion processes and formation of soluble weathering products over a broad range of times in the paleoenvironmental history of the surface of Mars. Many of the same minerals (smectite-group clay minerals, Ca-sulfates, Mg-sulfates, and the K-Fe–sulfate jarosite) have been identified both in the Martian meteorites and from remote sensing of the Martian surface. -
New Unique Pyroxene Pallasite: Northwest Africa 10019 C
78th Annual Meeting of the Meteoritical Society (2015) 5084.pdf NEW UNIQUE PYROXENE PALLASITE: NORTHWEST AFRICA 10019 C. B. Agee, K. Ziegler, N. Muttik. Institute of Meteoritics and the Department of Earth and Planetary Sciences, University of New Mexico. E-mail: [email protected]. Introduction: Pyroxene pallasites were originally defined by the grouplet of Vermillion and Yamato 8451 [1], which have minor amounts (~1-3 vol%) of pyroxene, with oxygen isotope values that are distinct from the pallasite main group (PMG) and the Eagle Station grouplet (PES). In the meantime, additional pyroxene-bearing pallasites, Zinder, NWA 1911, and Choteau, have been discovered [2,3], however each of these meteorites appears to be unique based on oxygen isotopes and mineralogy -- thus not belonging to the original pyroxene pallasite grouplet. Here we report on yet another unique ungrouped pyroxene pallasite, Northwest Africa 10019, which now brings the total of distinct pyroxene pallasite types – possibly all from different parent bodies – to a total of five. History and Physical Chracteristics: NWA 10019 was purchased by Steve Arnold from Morocco in January 2015 and consisted of one 580 gram fusion crusted individual and 26 grams of several small fusion crusted pieces. Saw cuts and thin slices show angular orange-brown-green, translucent olivines (~50 vol%), the largest 28 mm long, with many smaller (0.5-5 mm) angular grains, some of which are darker colored orthopyroxenes (Fs15.4±0.2Wo1.0±0.2, Fe/Mn=23±1, n=6, ~10 vol %), all set in a matrix of taenite (Fe=72.0±4.0, Ni=27.4±2.4, Co=0.19±0.05 wt%, n=5, ~20 vol%) and kamacite (Fe=93.1±2.0, Ni=6.6±0.2, Co=0.61±0.03 wt%, n=4, ~15 vol %).