DOCSLIB.ORG

Abstracts of the 8 European Science Identified to Be Responsible for This Fractionation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Abstracts of the 8 European Science Identified to Be Responsible for This Fractionation Large Meteorite Impacts (2003) alpha_p-s.pdf Contents — P through S Estimations of Axial Moment of the Growing Earth G. V. Pechernikova and I. W. Davidenko............................................................................................... 4015 The Suvasvesi South Structure, Central Finland: Further Evidences of Impact L. J. Pesonen, F. Donadini, J. Salminen, and M. Lehtinen .................................................................... 4074 Starting Conditions for Hydrothermal Systems Underneath Martian Craters: 3D Hydrocode Modeling E. Pierazzo, N. A. Artemieva, and B. A. Ivanov ..................................................................................... 4102 Recent Research in the Chesapeake Bay Impact Crater, USA — Part 1. Structure of the Western Annular Trough and Interpretation of Multiple Collapse Structures D. S. Powars, G. S. Gohn, R. D. Catchings, J. W. Horton Jr., and L. E. Edwards ................................ 4053 Strangelove Ocean and Deposition of Unusual Shallow-Water Carbonates After the End-Permian Mass Extinction M. R. Rampino and K. Caldeira............................................................................................................. 4077 Magnetostratigraphy of the K/T Boundary from Yaxcopoil-1 Borehole, Chicxulub Impact Crater M. Rebolledo-Vieyra and J. Urrutia-Fucugauchi .................................................................................. 4012 Authigenic and Allogenic Impact Breccias — Open Questions W. U. Reimold, B. O. Dressler, and C. Koeberl..................................................................................... 4036 Structural Characteristics of the Sudbury Impact Structure, Canada, Point to a Protracted Tectonomagmatic Evolution of the Sudbury Igneous Complex U. Riller and B. O. Dressler................................................................................................................... 4045 Bajo Hondo, a Very Puzzling Crater in Chubut, Patagonia, Argentina M. C. L. Rocca........................................................................................................................................ 4001 Estancia Los Mellizos: A Potential Impact Structure in Santa Cruz, Patagonia, Argentina, South America M. C. L. Rocca........................................................................................................................................ 4003 Potential Impact Sites in Southern Argentina: Simple Craters? M. C. L. Rocca........................................................................................................................................ 4002 Mass-Movement in Geological Strata of Some Astroblemes J. Rondot ................................................................................................................................................ 4007 Structural Investigations in the Central Uplift of the Upheaval Dome Impact Crater, Utah D. Scherler, A. Jahn, and T. Kenkmann ................................................................................................. 4072 Composition of the Late Influx of the Earth G. Schmidt.............................................................................................................................................. 4006 The ICDP Drill Core Yaxcopoil-1, Chicxulub Impact Crater, Mexico: Shock Metamorphism of the Impactite Units (794–894 m) R. T. Schmitt, A. Wittmann, and D. Stöffler............................................................................................ 4061 Large Meteorite Impacts (2003) alpha_p-s.pdf Internal Shearing and Subsurface Erosion from the Chicxulub Ejecta Blanket (Albion Fm.), Quintana Roo, Mexico F. Schönian, T. Kenkmann, and D. Stöffler............................................................................................ 4128 Additional Observations on the Impact Breccias of the Chicxulub Ejecta Blanket from the UNAM-7 Drill Core, Yucatán, Mexico F. Schönian, T. Salge, D. Stöffler, and J. Urrutia Fucugauchi .............................................................. 4132 “Fingerprinting” Target Lithologies of the Chicxulub Crater in Ejecta from NE Mexico and Texas: Yucatán Subsurface Revisited P. Schulte, A. Kontny, and W. Stinnesbeck............................................................................................. 4090 Al-rich Orthopyroxenes in Impact Melt Coatings of Gneiss Bombs from Popigai, Russia — New ATEM Data A.-M. Seydoux-Guillaume, A. Deutsch, and R. Wirth............................................................................. 4085 Shocked Quartz at the Permian-Triassic Boundary (P/T) in Spiti Valley, Himalaya, India A. D. Shukla, N. Bhandari, and P. N. Shukla ......................................................................................... 4059 Cratering Process After Oblique Impacts V. V. Shuvalov ........................................................................................................................................ 4130 Mechanisms of Tsunami Generation by Impacts V. V. Shuvalov ........................................................................................................................................ 4131 Experimentally Shock-loaded Anhydrite: Unit-Cell Dimensions, Microstrain and Domain Size from X-Ray Diffraction R. Skála and F. Hörz .............................................................................................................................. 4093 Diaplectic Glass Content in Experimentally Shock-loaded Quartz Determined by X-Ray Powder Diffraction R. Skála, F. Hörz, and F. Langenhorst................................................................................................... 4033 Chilling Evidence for the Bulk Composition of the Impact Melt Sheet at Sudbury: Evidence from Offset Dykes J. G. Spray, A. J. Murphy, C. S. J. Shaw, and M. G. Tuchscherer ......................................................... 4101 Yaxcopoil-1 and the Chicxulub Impact W. Stinnesbeck, G. Keller, T. Adatte, M. Harting, and D. Stüben.......................................................... 4037 Origin and Emplacement of the Impact Formations at Chicxulub, Mexico, with Special Emphasis on the Yax-1 Deep Drilling D. Stöffler, B. A. Ivanov, L. Hecht, T. Kenkmann, R. T. Schmitt, T. Salge, F. Schönian, R. Tagle, S. Weseler, and A. Wittmann................................................................................................... 4092 Simulations of Very Large Impacts on the Earth V. V. Svetsov........................................................................................................................................... 4133 Large Meteorite Impacts (2003) 4015.pdf ESTIMATIONS OF AXIAL MOMENT OF THE GROWING EARTH G.V. Pechernikova, I.W. Davidenko, Institute for Dynamics of Geospheres RAS, 38 Lenin- sky prosp. (bldg. 1), 119334 Moscow, Russia, [email protected]. Introduction. 30 yrs of analytical modeling calculated according to analytical theory [5- and numerical simulation have revealed two 7] and impacts of largest bodies to the general stages in the terrestrial accretion planet are treated statistically. We assume process: 1) stage in which planetesimals ex- complete mergers upon collisions in all perience runaway growth and form lunar- cases. sized “planetary embryos” in approximately I. Analytical part. According to [5] we 105 − 106 years; and 2) final stage domi- have v = (Gm/θ r) 1/2 ∝ m 1/3, where θ ~ 2, m nated by mutual gravitational perturbations is the mass of the growing planet. Such 1/3 between embryos, resulting in large, sto- quantities as ∆R ≅eR ≅vR/V K ∝ m , σ d = 2/3 2 chastic impact events and formation of the σ 0 [1 –(m/m ⊕ ) ], σ 0 = 10 g/cm , M = [1 – 8 2/3 − 2/3 final terrestrial planets after about 10 (m/m ⊕ ) ]m, Q = (m/m ⊕ ) m (here V K is the years. Recent dynamical models of lunar Kepler circular velocity at the distance R, formation in the giant impact scenario have m ⊕ is the present Earth’ mass) are calcu- raised new complicating issues. It was lated as functions of m. The time of the shown that (a) the angular momentum of the planet growth to the mass m is Earth-Moon system could have resulted from 1/3 1/3 t=(t 0 /P ⊕ )ln[(1 + (m/m ⊕ ) )/(1 − (m/m ⊕ ) )], more than one impact, (b) the moon-forming where t 0 /P ⊕ = δ r⊕ /[2(1+2θ)σ 0 ]. impact may not have been the last large im- It is suggested that the angular momentum pact on the Earth [1-3]. vector for the axial spin of a planet K, in- Some tentative results of calculations of clined at an angle ε to axis z (z is perpen- mass increase of the planet m and corre- dicular to the orbital plane), is equal to the sponding planetary spin K in the new model sum of the regular component K , which is [4] are presented. Our aim is to estimate the 1 directed along axis z and the random com- number of macro-impacts (with masses m imp ponent K , which is inclined at an angle γ to > 1026 g) and impact angular momenta and 2 z. K is calculated as a function of mass m the evolution of planetary spins during the 1 according to [5, 6]. late stage of terrestrial planet formation in II. Simulation. We calculated a growth dy- the framework Standard Scenario of the So- namics beginning from the initial value of lar System formation [5-9] with the use of new model. the mass m = 0.001 m ⊕ . At every step of Up to now there is a competition between calculation, the values of parameters enu- the model where planets are gradually spun merated in the previous section were calcu- up and another model where a massive late- lated. Then, one
Load more

Recommended publications
  • A PROTEROZOIC 40Ar/39Ar AGE for the SUVASVESI SOUTH STRUCTURE (FINLAND)
    72nd Annual Meteoritical Society Meeting (2009) 5076.pdf A PROTEROZOIC 40Ar/39Ar AGE FOR THE SUVASVESI SOUTH STRUCTURE (FINLAND). E. Buchner1, M. Schmieder1, W. H. Schwarz2, M. Trieloff2, J. Moilanen3, T. Öhman4 and H. Stehlik5. 1Institut für Planetologie, Universität Stuttgart, D-70174 Stuttgart, Germany. Email: [email protected]. 2Institut für Geowissenschaften, Universität Heidelberg, D-69120 Heidelberg. 3Pinkelikatu 6 B 48, FI-90520 Oulu, Finland. 4Department of Geosciences, FI-90014 University of Oulu, Finland. 5Hagedornweg 2/2/12, A-1220 Vienna, Austria Introduction: The Suvasvesi North (diameter ~3.5 km) and South (diameter ~4.0 km) structures [1-3] in Finland are thought to represent a double impact crater system, similar to the Clearwater lakes in Canada [4]. As no isotopic data have so far been available, only the age of the ~1.88 Ga Paleoproterozoic (and some ~2.7 Ga Archean) crystalline target rocks of the Baltic Shield [1] is cited as the maximum impact age. Paleomagnetic data suggested either a Permo-Triassic (~230-280 Ma) or a Neoproterozoic (770-790 Ma) age for the Suvasvesi North impact structure [4,5]. We here present the first 40Ar/39Ar age for the Suvasvesi South structure. Samples and analytical procedure: Clast-poor particles of impact melt rock (87.1 mg) recovered by one of the authors (J. M.) from the Mannamäki area were chosen for 40Ar/39Ar dat- ing at the University of Heidelberg [6,7]. Results and interpretation: 40Ar/39Ar step-heating analysis yielded no plateau within a perturbed, hump-shaped [8] age spectrum with younger apparent ages (~100-450 Ma) within the low-temperature (T) heating steps (~13% of 39Ar released), older apparent ages (~820 Ma) in the mid-T fractions (~47% of 39Ar), and intermediate apparent ages (~715-710) Ma in the four final high-T steps (~40% of 39Ar).
    [Show full text]
  • Impact Structures and Events – a Nordic Perspective
    107 by Henning Dypvik1, Jüri Plado2, Claus Heinberg3, Eckart Håkansson4, Lauri J. Pesonen5, Birger Schmitz6, and Selen Raiskila5 Impact structures and events – a Nordic perspective 1 Department of Geosciences, University of Oslo, P.O. Box 1047, Blindern, NO 0316 Oslo, Norway. E-mail: [email protected] 2 Department of Geology, University of Tartu, Vanemuise 46, 51014 Tartu, Estonia. 3 Department of Environmental, Social and Spatial Change, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark. 4 Department of Geography and Geology, University of Copenhagen, Øster Voldgade 10, DK-1350 Copenhagen, Denmark. 5 Division of Geophysics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki, Finland. 6 Department of Geology, University of Lund, Sölvegatan 12, SE-22362 Lund, Sweden. Impact cratering is one of the fundamental processes in are the main reason that the Nordic countries are generally well- the formation of the Earth and our planetary system, as mapped. reflected, for example in the surfaces of Mars and the Impact craters came into the focus about 20 years ago and the interest among the Nordic communities has increased during recent Moon. The Earth has been covered by a comparable years. The small Kaalijärv structure of Estonia was the first impact number of impact scars, but due to active geological structure to be confirmed in northern Europe (Table 1; Figures 1 and processes, weathering, sea floor spreading etc, the num- 7). First described in 1794 (Rauch), the meteorite origin of the crater ber of preserved and recognized impact craters on the field (presently 9 craters) was proposed much later in 1919 (Kalju- Earth are limited.
    [Show full text]
  • Rocks, Soils and Surfaces: Teacher Guide
    National Aeronautics and Space Administration ROCKS, SOILS, AND SURFACES Planetary Sample and Impact Cratering Unit Teacher Guide Goal: This activity is designed to introduce students to rocks, “soils”, and surfaces on planetary worlds, through the exploration of lunar samples collected by Apollo astronauts and the study of the most dominant geologic process across the Solar System, the impact process. Students will gain an understanding of how the study of collected samples and impact craters can help improve our understanding of the history of the Moon, Earth, and our Solar System. Additionally, this activity will enable students to gain experience with scientific practices and the nature of science as they model skills and practices used by professional scientists. Objectives: Students will: 1. Make observations of rocks, “soil”, and surface features 2. Gain background information on rocks, “soil”, and surface features on Earth and the Moon 3. Apply background knowledge related to rocks, soils, and surfaces on Earth toward gaining a better understanding of these aspects of the Moon. This includes having students: a. Identify common lunar surface features b. Create a model lunar surface c. Identify the three classifications of lunar rocks d. Simulate the development of lunar regolith e. Identify the causes and formation of impact craters 4. Design and conduct an experiment on impact craters 5. Create a plan to investigate craters on Earth and on the Moon 6. Gain an understanding of the nature of science and scientific practices by: a. Making initial observations b. Asking preliminary questions c. Applying background knowledge d. Displaying data e. Analyzing and interpreting data Grade Level: 6 – 8* *Grade Level Adaptations: This activity can also be used with students in grades 5 and 9-12.
    [Show full text]
  • Supportive Comment On: “Morphology and Population of Binary Asteroid
    *Manuscript Click here to view linked References 1 Supportive comment on: “Morphology and population of binary asteroid 2 impact craters” , by K. Miljković , G. S. Collins, S. Mannick and P. A. 3 Bland [Earth Planet. Sci. Lett. 363 (2013) 121 –132] – An updated 4 assessment 5 6 Martin Schmieder 1,2 , Mario Trieloff 3, Winfried H. Schwarz 3, Elmar Buchner 4 and Fred Jourdan 2 7 1School of Earth and Environment, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia 8 2Western Australian Argon Isotope Facility, Department of Applied Geology and JdL Centre, Curtin University, GPO Box 9 U1987, Perth, WA 6845, Australia 10 3Institut für Geowissenschaften, Universität Heidelberg, Im Neuenheimer Feld 234-236, D-69120 Heidelberg, Germany 11 4HNU-Neu-Ulm University, Edisonallee 5, D-89231 Neu-Ulm, Germany 12 13 In their recent paper, Miljković et al. (2013) assess the appar ent contradiction that the near-Earth asteroid population 14 consists of 15% binaries, while the terrestrial (and Martian) impact crater populations have only 2-4% of observable 15 doublet craters. The authors suggest that only a small fraction of sufficiently well separated binary asteroids yield 16 recognizable doublets. We generally agree with the conclusions by Miljković et al. (2013) and acknowledge the high 17 quality and relevance of the study. However, we would like to bring into focus additional geochronologic constraints 18 that are critical when evaluating terrestrial impact crater doublets. Miljković et al. (2013) appraised five potential 19 terrestrial doublets using the Earth Impact Database (EID; as of 2010). We hereby warn against the indiscriminate 20 usage of impact ages compiled in this database without an assessment based on solid isotopic and stratigraphic 21 constraints and comment on the geological, geochronological, and geochemical evidence for doublet impact craters 22 on Earth.
    [Show full text]
  • Ni in Impactite Sulphides in the Lappajärvi, Sääksjärvi, Suvasvesi S, 1,2 and Paasselkä Meteorite Craters in Finland
    Lunar and Planetary Science XXXVII (2006) 1676.pdf NI IN IMPACTITE SULPHIDES IN THE LAPPAJÄRVI, SÄÄKSJÄRVI, SUVASVESI S, 1,2 AND PAASSELKÄ METEORITE CRATERS IN FINLAND. D. D. BADJUKOV AND J. 2 1 RAITALA ; V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry RAS, 119991, 19, Kosygin str., Moscow, Russia ([email protected]), 2University of Oulu, P.O. Box 3000, FIN-90401, Oulu, Finland ([email protected]) Introduction: The craters are situated in Bravoite is present also in strongly re- the central part of Finland and were formed crystallized impact melt rocks of the in crystalline rocks. The melt rocks at these Paasselkä impact crater. Finnish meteorite craters are enriched in According to morphologic and siderophile elements and other meteoritic composition features, a fraction of sulphides components [1,2]. Contents of a meteoritic and metal in Lappajärvi and Sääksjärvi matter are around 2 – 0.1 % of a nominal CI impactites are a shock re-worked meteorite component and the distributions are matter, that experienced shock-induced heterogeneous on a fine scale [3,4]. melting or, less likely, are condensates of Sulphides in the impact melt rocks are main impact generated vapour cloud [5]. carriers of siderophile elements, especially Other fraction of sulphides and metal for Ni and Co. with low Ni and Co contents has terrestrial The studied impactites: The Lappajärvi origin and formed by shock melting of a melt rocks contain pyrrhotite droplets and target. The reduced from target rocks and oxide-silicate globules (d < 2 mm) rich in Ni Fe-sulphide metal suggests to be slightly rimmed by pyrrhotite and occasionally with enriched in Ni and Co due to presence of pentlandite and chalcopyrite.
    [Show full text]
  • Effects of Asteroid and Comet Impacts on Habitats for Lithophytic Organisms—A Synthesis
    Meteoritics & Planetary Science 40, Nr 12, 1901–1914 (2005) Abstract available online at http://meteoritics.org Effects of asteroid and comet impacts on habitats for lithophytic organisms—A synthesis Charles S. COCKELL1*, Pascal LEE2, Paul BROADY3, Darlene S. S. LIM2, Gordon R. OSINSKI4, John PARNELL5, Christian KOEBERL6, Lauri PESONEN7, and Johanna SALMINEN7 1Planetary and Space Sciences Research Institute, Open University, Milton Keynes. MK7 6AA, UK 2NASA Ames Research Center, Moffett Field, California 94035–1000, USA 3School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand 4Canadian Space Agency, 6767 Route de l’Aeroport, Saint-Hubert, Quebec, J3Y 8Y9, Canada 5Department of Geology, University of Aberdeen, Aberdeen, AB24 3UE, UK 6Department of Geological Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria 7Division of Geophysics, Department of Physical Sciences, University of Helsinki, P.O. Box 64, 00014 University of Helsinki, Finland *Corresponding author. E-mail: [email protected] (Received 04 April 2005; revision accepted 03 August 2005) Abstract–Asteroid and comet impacts can have a profound influence on the habitats available for lithophytic microorganisms. Using evidence from the Haughton impact structure, Nunavut, Canadian High Arctic, we describe the role of impacts in influencing the nature of the lithophytic ecological niche. Impact-induced increases in rock porosity and fracturing can result in the formation of cryptoendolithic habitats. In some cases and depending upon the target material, an increase in rock translucence can yield new habitats for photosynthetic cryptoendoliths. Chasmoendolithic habitats are associated with cracks and cavities connected to the surface of the rock and are commonly increased in abundance as a result of impact bulking.
    [Show full text]
  • The Ries-Steinheim Crater Pair and Two Major Earthquakes – New Discoveries Challenging the Double-Impact Theory
    The Ries-Steinheim crater pair and two major earthquakes – New discoveries challenging the double-impact theory Elmar Buchner ( [email protected] ) University of Applied Sciences Neu-Ulm Volker Sach Meteorkratermuseum Steinheim Martin Schmieder USRA, Houston, Texas Article Keywords: impact-earthquakes, Nördlinger Ries, Steinheim Basin Posted Date: July 27th, 2020 DOI: https://doi.org/10.21203/rs.3.rs-43745/v1 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Page 1/24 Abstract The Nördlinger Ries and the Steinheim Basin are widely perceived as a Middle Miocene impact crater doublet. We discovered two independent earthquake-produced seismite horizons in North Alpine Foreland Basin deposits. The older seismite horizon,associated with the Ries impact is overlain by in situ-preserved distal impact ejecta, forming a unique continental seismite-ejecta couplet within a distance up to 180 km from the crater. The younger seismite unit, also triggered by a major palaeo-earthquake, comprises clastic dikes that cut through the Ries seismite-ejecta couplet. The clastic dikes were likely formed in response to the Steinheim impact, some kyr after the Ries impact, in line with paleontologic results. With the Ries and Steinheim impacts as two separate events, Southern Germany witnessed a double disaster in the Middle Miocene. The magnitude–distance relationship of seismite formation during large earthquakes suggests the seismic and destructive potential of impact-earthquakes may be signicantly underestimated. Introduction The ~24 km-diameter Nördlinger Ries1,2,3,4 and the ~4 km-diameter Steinheim Basin1,5,6,7,8 impact structures in southern Germany (Fig.
    [Show full text]
  • The Geological Record of Meteorite Impacts
    THE GEOLOGICAL RECORD OF METEORITE IMPACTS Gordon R. Osinski Canadian Space Agency, 6767 Route de l'Aeroport, St-Hubert, QC J3Y 8Y9 Canada, Email: [email protected] ABSTRACT 2. FORMATION OF METEORITE IMPACT STRUCTURES Meteorite impact structures are found on all planetary bodies in the Solar System with a solid The formation of hypervelocity impact craters has surface. On the Moon, Mercury, and much of Mars, been divided, somewhat arbitrarily, into three main impact craters are the dominant landform. On Earth, stages [3] (Fig. 2): (1) contact and compression, (2) 174 impact sites have been recognized, with several excavation, and (3) modification. A further stage of more new craters being discovered each year. The “hydrothermal and chemical alteration” is also terrestrial impact cratering record is critical for our considered as a separate, final stage in the cratering understanding of impacts as it currently provides the process (e.g., [4]), and is also described below. only ground-truth data on which to base interpretations of the cratering record of other planets and moons. In this contribution, I summarize the processes and products of impact cratering and provide and an up-to-date assessment of the geological record of meteorite impacts. 1. INTRODUCTION It is now widely recognized that impact cratering is a ubiquitous geological process that affects all planetary objects with a solid surface (e.g., [1]). One only has to look up on a clear night to see that impact structures are the dominant landform on the Moon. The same can be said of all the rocky and icy bodies in the solar system that have retained portions of their earliest crust.
    [Show full text]
  • Impact Melt Rocks from the Paasselkä Impact Structure (SE Finland): Petrography and Geochemistry
    Impact melt rocks from the Paasselkä impact structure (SE Finland): Petrography and geochemistry Item Type Article; text Authors Schmieder, M.; Moilanen, J.; Buchner, E. Citation Schmieder, M., Moilanen, J., & Buchner, E. (2008). Impact melt rocks from the Paasselkä impact structure (SE Finland): Petrography and geochemistry. Meteoritics & Planetary Science, 43(7), 1189-1200. DOI 10.1111/j.1945-5100.2008.tb01122.x Publisher The Meteoritical Society Journal Meteoritics & Planetary Science Rights Copyright © The Meteoritical Society Download date 23/09/2021 21:32:30 Item License http://rightsstatements.org/vocab/InC/1.0/ Version Final published version Link to Item http://hdl.handle.net/10150/656454 Meteoritics & Planetary Science 43, Nr 7, 1189–1200 (2008) Abstract available online at http://meteoritics.org Impact melt rocks from the Paasselkä impact structure (SE Finland): Petrography and geochemistry Martin SCHMIEDER1*, Jarmo MOILANEN2, and Elmar BUCHNER1 1Institut für Planetologie, Universität Stuttgart, Herdweg 51, D-70174 Stuttgart, Germany 2Vuolijoentie 2086, FIN-91760 Säräisniemi, Finland *Corresponding author. E-mail: [email protected] (Received 06 March 2007; revision accepted 09 January 2008) Abstract–Recently, samples of allochthonous melt rocks from the ∼10 km and ≤1.9 Ga Paasselkä impact structure, SE Finland, were obtained. In this study, we present a first detailed petrographic and geochemical description of clast-rich Paasselkä impact melt rocks. Shock metamorphic features comprise shocked feldspar grains, intensely shocked and toasted quartz, marginally molten and recrystallized clasts thought to have been diaplectic quartz glass, largely fresh and recrystallized feldspar glasses, decomposed biotite flakes, recrystallized fluidal silica glass (originally probably lechatelierite) in partially molten sandstone clasts, all set into a glassy to cryptocrystalline melt matrix.
    [Show full text]
  • LARGE METEORITE IMPACTS and Planetary EVOLUTION September 1-3,1997 Sudbury, Ontario CONFERENCE on LARGE METEORITE IMPACTS and PLANETARY EVOLUTION (SUDBURY1997)
    NASA/CR- - 207991 BURY 1997 LARGE METEORITE IMPACTS AND PlANETARY EVOLUTION September 1-3,1997 Sudbury, Ontario CONFERENCE ON LARGE METEORITE IMPACTS AND PLANETARY EVOLUTION (SUDBURY1997) Hosted by Ontario Geological Survey Sponsored by Inco Limited Falconbridge Limited The Bamnger Crater Company Geological Survey of Canada Ontario Ministry of Northern Development and Mines Quebec Ministere des Ressources naturelles Lunar and Planetary Institute Scientific Organizing Committee A. Deutsch University ofMunster, Germany B. O. Dressier, Chair Lunar and Planetary Institute, Houston, Texas B. M. French Smithsonian Institution, Washington, DC R. A. F. Grieve Geological Survey of Canada, Ottawa, Ontario G. W. Johns Ontario Geological Survey, Sudbury, Ontario V. L. Sharpton Lunar and Planetary Institute, Houston, Texas LPI Contribution No. 922 Compiled in 1997 by LUNAR AND PLANETARY INSTITUTE The Institute is operated by the Universities Space Research Association under Contract No. NASW-4574 with the National Aeronautics and Space Administration. Material in this volume may be copied without restraint for library, abstract service, education, or personal research purposes, however, republication of any paper or portion thereof requires the written permission of the authors as well as the appropriate acknowledgment of this publication. Abstracts in this volume may be cited as Author A. B. (1997) Title of abstract. In Conference on Large Meteorite Impacts and Planetary Evolution (Sudbury 1997), p. XX, LPI Contribution No. 922, Lunar and Planetary Institute, Houston. This volume is distributed by ORDER DEPARTMENT Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113, USA Mail order requestors will be invoiced for the cost of shipping and handling. LPI Contribution No 922 ill Contents BP and Oasis Impact Structures, Libya, and Their Relation to Libyan Desert Glass: Petrography, Geochemistry, and Geochronology B.
    [Show full text]
  • Science Article on Fast-Breaking Items Or Current Topics of General Inter- Some Errors
    Vol. 5, No. 10 October 1995 INSIDE • Aerial Photos by Washburn, p. 200 • Call for Award Nominations, p. 203 • Rocky Mountain Section Meeting, GSA TODAY p. 206 A Publication of the Geological Society of America • Cordilleran Section Meeting, p. 207 Figure 2. Topography of the Manicouagan complex impact The Record of Terrestrial structure, Quebec, Canada. The original diameter of this Impact Cratering 214 ± 1 Ma structure is esti- mated to have been 100 km. Richard Grieve, James Rupert, Janice Smith, Ann Therriault Erosion, however, has removed the rim, and the structure Continental Geoscience Division. Geological Survey of Canada appears as a series of circular Ottawa, Ontario K1A 0Y3, Canada features with positive and nega- tive relief, beginning with a 150-km-diameter outer fracture zone, seen most easily in the western and southern sectors, ABSTRACT INTRODUCTION and culminating in slightly off- center topographic peaks. The Approximately 150 terrestrial The first studies of a terrestrial annular Manicouagan reservoir impact structures are currently impact structure, of the now famous (dark green area slightly left of known, representing a small, biased Meteor or Barringer Crater, Arizona, in center) is ˜65 km in diameter sample of a much larger population. the early 1900s by D. M. Barringer and and at ˜360 m elevation. Eleva- The spatial distribution indicates colleagues, produced more controversy tions in the center are as much as 1100 m (brown). concentrations in cratonic areas— than acceptance. There was, however, a ˜ in particular, ones where there have gradual increase in the number of rec- been active search programs. The ognized small craters with meteorite majority of the known impact struc- fragments until the 1960s, when so- tures are <200 m.y.
    [Show full text]
  • PLANETAARINEN GEOFYSIIKKA 2011 Tänään!
    PLANETAARINEN GEOFYSIIKKA 2011 Aikataulu, Kl 2011- Periodit III&IV; Luennoitsijat L.J. Pesonen, M. Poutanen ja K. Muinonen; kurssiassistenttina Olli Wilkman Luennot maanantaisin klo 12-14 Physicum E206 ellei toisin mainita 17.1.11 Kurssin esittely, käytännön asiat +Johdantoluento, Lauri, Karri ja Markku 2h 24.1.11 Maailmankaikkeuden ja aurinkokunnan synty ja rakenne, Markku 2h 31.1.11 Taivaanmekaniikan perusteet, satelliittien/planeettojen radat ja liikkeet, Markku 2h 07.2.11 Lähiavaruuden asteroidit ja komeetat sekä törmäykset, Karri 2h 04.2.11 Neptunuksen takaiset kohteet, Karri 2h 21.2.11 Painovoima, vetovoima, vaikutukset ja mittaaminen, Markku 2h 28.2.11 Jupiter-järjestelmä ja Galileo-luotain, Karri 2h 07.3.11 Väliviikko: ei luentoa 14.3.11 Harjoitusten I osan palautus (4 pakollista + 4 vapaaehtoista tehtävää), Olli 14.3.11 Saturnus-järjestelmä ja Cassini-Huygens-luotain, Karri 2h 14.3.11 Harjoitusten osan I tehtävien läpikäynti, Olli 21.3.11 Uranus ja Neptunus-järjestelmät, Karri 2h 28.3.11 Törmäyskraattereista, Lauri 2h 04.4.11 Meteoriittien ja asteroidien fysikaaliset ominaisuudet, Lauri 2h tänään! 11.4.11 Maankaltaiset planeetat I, Lauri 2h 18.4.11 Maankaltaiset planeetat II, Lauri 2h 25.4.11 Pääsiäismaanantai: ei luentoa 02.5.11 Harjoitusten II osan palautus (4 pakollista + 4 vapaaehtoista tehtävää), Olli 02.5.11 Harjoitusten osien I/2 tehtävien läpikäynti, Olli 1h (Huom: laskarit ovat 20% ja ekskursio 5% arvosanasta!) 02.5.11 Ekskursio geofysiikan laboratorioon (meteoriitteja, kuunäytteitä jne), Lauri 1h 09.5.11 Tentti (Sali, aikataulu vielä auki) ...75% arvosanasta 1 Planetaarinen geofysiikka 2011 Törmäskraattereista L.J. Pesonen TÖRMÄYSKRAATTEREISTA Lauri J. Pesonen Kiinteän maan geofysiikka Helsingin yliopisto • Törmäyskraattereiden rooli planeettojen kehityksessä • Planeetta Maan törmäyskraattereista: koko, muoto, iät: Geofysiikan rooli tutkimuksissa • Kuinka tunnistaa törmäyskraatteri? - energia, shokkimuutokset kivissä • Joukkotuhot ja suuret törmäykset.
    [Show full text]