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Download Full Article 15.6MB .Pdf File Memoirs of the National Museum of Victoria 1 July 1959 https://doi.org/10.24199/j.mmv.1959.23.01 TEKTITES by George Baker, D.Sc (Melbourne) ————— . .. .. CONTENTS PAGE List op Frustrations . 8, 9 Author's Preface . 10 Chapter [.— Introduction. General Distribution and Types of Tektites. Mode of Occurrence and Locations. Collecting and Collections .. .. 11 Chapter II.—- Tektite Terminology -Shape Terms, Structure Terms. Classification. 32 Chapter III.- The Nature of Tektite Glass—Optical Properties, Weight, Specific Gravity, Hardness, Behaviour to Heat . 42 Chapter [V.— External Surface Features (Sculpture). The Flanges of Australites. The Curvature of Tektite Surfaces . 61 Chapter v.— internal Structures of Tektites—Flow Structures, Inclusions, Gas Content . 82 Chapter VI. The Chemistry of Tektites . 94 Chapter VII.— Theories of Palls. Time of Arrival on the Earth's Surface. Age of Tektites . .. .. .. .. ..Ill Chapter VIII. The Origin of Tektites -Theories of Artificial and Terrestrial Modes of Origin . 120 Chapter IX. The Origin of Tektites—Theories of Extra-Terrestrial Origin .. 130 Chapter X.— The Origin arid Relationship of Tektite Shapes . 148 Chapter X L— The Origin of the Surface Features (Sculpture) of Tektites . 174 Chapter XII.— Motion, Velocity and Fragmentation of Tektites .. ,, ..181 Chapter XIII.— The Uses of Tektites. Vernacular Terminology . 187 Chapter XIV. Analogous Structures and Materials. Pseudo-tektites and " " Amerikanites .. .. .. .. ..191 Chapter XV. Experiments with and relating to Tektites .. .. .. 199 ('hapten XVI. Natural Glasses of Meteoritic. Lightning and I'nknown Origins . 207 Chapter XVI r. The Status of Tektite Origin. Summary of Fssential Fact and Theory 227 . bibliography . 231 Author Index .. .. .. .. .. .. 247 . Locality Index . 253 . Subject Index . , 260 TEXT FIGURES Pa Frontispiece: The Tektite Strewnfields of the World ,. .. Fig. 1.—Moldavite localities . ..12 Fig. 2. —Rizalite—billitonite- javaite localities . ..II Fig. 3.—Malaysianite and indochinite localities .. .. ]fl FlG. 4. —Australite localities in Australia .. .. ]*< Fig. 5. Australite localities — in Tasmania . 2" FlG. 6. —Bediasite localities in the United States of America .. ..22 Fig. 7. (?)Tektite localities in — South America .. .. ..2 1 Fig. 8. —Diagram illustrating australite nomenclature .. .. :i7 9. Fig. —The specific refractivity of tektites. .. .. ..!.*> Fig. 10.—Refractive index — specific gravity relationships in tektites .. n; Fig. 11. — Refractive index—silica relationships in tektites ..IT Fig. 12. —Specific gravity distribution in australites .. ..."»! Fig. IS.— Variation diagram showing relationship between specific gravity and ">'. silica in tektites. Fig. 14. - —Dilatation curve for indochinite .. .. s Fig. 15.—Teardrop-shaped australite showing wrinkled flow ridges 07 Fig. 10.— Diagrams illustrating shapes and positions of rims and flanges Oil 7(1 australites Fig. 17.—Relationship of the curvature of australite surfaces ;;; Fig. 18. —Curvature of anterior and posterior surfaces of various australite 77 shapes FlG. 19.—Scatter diagram showing relationships of radius of curvature of hack 7s and front surfaces on australites Fig. 20.—Graph illustrating relationship between mass and curvature of front 7" surfaces on australites Fig. 21 —Diagram of hollow australite showing relationship of curvature of Kf] outer and inner walls FlG. 22. Lechatelierite particles - — in australites .... s Fig. 23.—Stretched and twisted lechatelierite particles in australite flanges Fig. 24.—Triangular diagrams showing MgO-CaO-Nu,<> and Mg()-Ca(>-UIV|UK < > im ' relationships in tektites. ' Pig. 25.—Triangular diagrams showing Xa,()-K 2 ()-Mg() and Na.O-K.O-CaO- - 10* relationships in tektites ' - Fig. 26 —Variation diagram for alumina, ferrous oxide and magnesia in and related glasses tektitesuwa IflMl •' FlG 2 ariati °n diagl' am ior ,otaHh " f * soda and lime in lIs^J tektites and related t0o a illUStmtinK geJ **^«™ hypothesis of australite °*lf^SSr | M Fig. 29.—Great circle theory of tektite distribution KG iagrammatic representation of the development "^^f of ' australite 152 Fig. 31.—Graph of depth— diameter relationships in australites r -. Fig. 32.—Diagram showing the development of a button-shaped ' australitel d,lu an original sphere rronafrom Il.»fTi Fig. Six stages 33.— in the development of button and lens-shaped australitesl from original spheres ' <' »*uauies IV,i.,.» FlG. 34. —Fluidal flow past a cylindrical body Fig. Sketch ''~ 35.— from a ! photograph of a bullet in flight, ' K anowshowing rWl™ I of shock waves ' ™8 development Mil Fig. 36.—Final stages of supersonic atmospheric flight ofot a 1„,h i australite K button-shaped 165 Fig. 37.—Fragmentation of the peripheral zones of australites Fig. 38.—Outline sketches of droplets from glass ", ," ° " b wool 'stoeIsteel ,i,'ihul (slag) bombs ' * an d smoke ]U\ Fig. 39.—Shapes formed by dropping clay suspension into clear w-.t ' 203 Fig. 40.—Sketch diagrams showing internal ' character of silica ela Fig. 41. —Sketch micro-section of a fulgurite 208 217 LIST OF PLATES Page. Plate I. Surface — structures of billitonites and australite cores . 269 Plate II. Surface — structures of indochinites . 271 Plate III. Surface — structures of moldavites . 273 Plate IV. Surface — structures of moldavites . 275 Plate V. Surface — structures of australites . 277 Plate VI. Surface structures — of indochinites . 279 Plate VII.—Surface structures of bediasites and photomicrographs of 281 lechatelierite particles and gas bubbles in tektites Plate VIII. —Flange of australite on button-shaped form . 283 Plate IX.—Flange of australite on boat-shaped form and wrinkled flow 285 ridges on dumb-bell-shaped form Plate X.—Boat-shaped australite core showing equatorial zone and button- 287 shaped australite showing internal flow structures Plate XI.—Flow structures in button-, boat-, lens-, and oval-shaped 289 australites Plate XII. —Flow structures in flanges of australites 291 Plate XIII.—Crystal, gas and glass inclusions in Peruvian tektite 293 Plate XIV.—Exterior and interior of bubble-bearing tektites 295 Plate XV,—Bubble pits on the surfaces of australites 297 Plate XVI.- -Bubble craters on indochinites 299 Plate XVII.—Photomicrographs of minute bubbles in indochinites 301 Plate XVIII. —Sculpture of indochinites 303 Plate XIX.-—Sculpture and shapes of rizalites 305 Plate XX.—Flattened rifle bullets. Straw silica glass. Artificially etched 307 indochmite showing flow lines Plate XXI. -Fragments of pseudo-tektite glass 309 Plate XXII.—Artificially produced external markings on colophany compared 311 with surface markings on an australite Plate XXTII. —Darwin Glass (Queenstownite) and fulgurites .. .. 313 TEKTITES By George Baker, D.Sc. (Melbourne). AUTHORS PREFACE. together the more ^rtarU In this monograph it is endeavoured to bring Stress has been laid more and interesting facts and ideas concerning tektites. acquaintance with them, ann particularly on australites because of a closer because of their unique shapes. considerably in the last two The literature dealing with tektites has grown astronomers ha\e decades. Many articles by mineralogists, geologists and centres of appeared with the discovery of new types of tektites and additional for over 100 years. concentration within the strewnfields of types already known sculpture have also The controversies prevalent concerning tektite origin and their favoured theory led to increased contributions from writers supporting of origin. Fenner (1940, The study of tektites has reached a stage when, to quote facts, and to correlate them where p 305)—" we should continue to accumulate regarding their origin. possible We should not suppress speculation and theory accumulation of Theories might well progress, step by step, with the far played a information " Physical scientists and mathematicians have so theories leading to the minor part in tektite studies, but may yet stimulate solving of certain problems peculiar to tektites. Linck, The works of F. E. Suess, R. H. Walcott, E. J. Dunn, H. Michel, G. Janoschek, A Lacroix, A. Rzehak, F. Berwerth, H. Otley Beyer, F. Heide, R. and others from among C. Fenner, L. J. Spencer, H. S. Summers, V. E. Barnes drawn upon in the the extensive literature on tektites, have been freely compilation of the chapters of this monograph. University Geology The author is grateful to staff members of the Melbourne Department, particularly to Professor E. S. Hills who originally suggested that University the work be undertaken, and to Dr. F. Loewe of the Melbourne Meteorological Department, for valuable help and criticism, also to Mr. J. Spencer Mann for many of the photographic preparations. The former Director of the Victorian Geological Survey, Mr. W. Baragwanath, granted access to the Victorian Mines Department's files on australites, supplied valuable information upon many matters relating to tektites in Victoria, and kindly permitted certain illustrations to be reproduced from articles written by E. J. Dunn. Mr. P. W. Crohn translated several foreign papers on the subject-matter of tektites. Thanks are due to M. K. Baker, E. Wall, A. J. Wall, R. E. Jacobson, E. D. Gill and others for their assistance in searches for australites in the southern portion of western Victoria. The manuscript in its initial stages, was read and criticized by A. B. Edwards, D.Sc, Ph.D., D.I.C., and by the late H. B. Hauser, M.Sc, and in its later stages by Dr. M. H. Hey and Dr. W. Campbell-Smith of the British Museum is to of Natural
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