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Radial structures surrounding lunar basins Item Type text; Thesis-Reproduction (electronic) Authors Hartmann, William K. Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 06/10/2021 23:41:39 Link to Item http://hdl.handle.net/10150/319774 RADIAL STRUCTURES SURROUNDING LUNAR BASINS by William K» Hartmann A Thesis Submitted to the Faculty of the .DEPARTMENT OF GEOLOGY In .Partial Fulfillment of the Requirements For the Degree of MASTER OF SCIENCE In the Graduate College . THE UNIVERSITY OF ARIZONA STATEMENT BY AUTHOR TtiA ttuesis hag been , submitted in partial fulfillment of require­ ments forvaE.advanced.-degr'ee.at The University of Arizona and is de­ posited in the University Library to be made available to borrowers under rules of the Library® Brief quotations: from this thesis are allowable without special permission® provided that accurate acknowledgment of source is made®. : Requests, for -permission for. extended quotation fr om Or .reproduction of this manuscr ipt in whole or in part may b e gr anted by the head of the major department or the Bean of the Graduate College w h en in his judg­ ment the proposed use of the material is in the interests of scholarship® In all other Instances, however, permission must be obtained from the author® SIGNED; APPROVAL BY THESIS DIRECTOR This thesis has been approved on the date shown below: S® Bo TITLpT Associate Professor of Geology AC KNOWLEBGME NTS I wish to thank Dre G.. P. Kuiper? Miss Barbara Ms Middlehurstg M essrs. Robert Strom, Be W. G. Arthur, and E. A® Whitaker, of. the Lunar and Planetary Laboratory, and Dr® Evans B® Mayo and Dr. Spencer Re Titley of the Bepartment of Geology for many helpful dis­ cussions® I r elied extensively on Mr* . Whitaker1 s help in selection of photographs from the Lunar and Planetary Laboratory plate collection® . Some of the rectified negatives were made by Mr®. Harold .Spradley* The work, was supported by the national Aeronautics and Space Administra­ tion through Grant NsG 161-61® .TABLE. OF CONTENTS LIST OF ILLUSTRATIONS <..<>. •. .o o = 0 o •»<><,»• eo»» -o .ee..« Ab s t r a c t ................................................................................ 1 UC_y TIQN . o . 0 . o . o . o .... o .... a ....... o ... o . THE IMBRIUM STSTE^/I ............ o...... Review of Literature ........... Morphology .................................... - o.ue.iu8torie . @..,..,..................o. * THE ORIENTALE SYSTEM .v.......... ..'........ Morphology .................................... : ' onehie ions ..................................... The n e c t Aris systeml ...... ........................... Morphology .............-----.................... Conclusions .o.........o.o........... THE HUMORUM SYSTEM ^ . Morphology ..................................... Conclusions .................................... THE CREIUM S YSTEM .................................. Morphology ............................ Conclusions ..................................... OTHER. M @ @ . GRID SYSTEMS ......................................... - V Page EADJA.Ii SYSTEMS AROUND CRATERS ..,............ 70 .CONCLUSIONS AND SUMMARY ............................. 78 APPENDIX I— PLATES ILLUSTRATING LUNAR .STRUCTURES ............ 82 REFERENCES .......___........................._____..... 150 LIST OF ILLUSTRATIONS Plat© Page 1. View of moon from above Mare Jmbrimm .................. 83 2, LooMng south from above Mare Imbrium .............. 84 3» The Apetinine Mountains and Mare VapOrum ............ 85 4. The Straight Wall .............................. 86 •5® The Cauchy scarp ..»* .............. ... ....... *...... $ 87 6. Haemus Mountains, sunrise .......................... 88 T* Haemus Mountains, sunset ^ ....... 89 8e Apennine Mountains and Mare Vaporum, sunrise ....... 90 90 Apennine Mountains and Mare Vaporum, full moon ....... 91 lOo Apennine Mountains and Mare Vaporum, sunset ........ 92 11. Region of Julius Caesar, sunrise ...................... 93 12. Region of Julius Caesar, sunset ...................... 94 13. Region of Ptolemaeus, sunrise ........................ 95 140 . Region of Ptolemaeus, full moon .......... 96 15o Region of Ptolemaeus, sunset ........................ 97 160 Region of Ar zachel, sunrise I ........................ 98 l'7o - Region of Ar zachel, sunr ise H ........... 9 9 18@ Region of Arzachel, full moon ........................ 100 vi vn Plate Page 19. Region of Arzachel, sunset ..........................101 20. Region of Arzachel with overlay ....................... 102 21. Region of Ptolemaeus with overlay ..................... 103 22. Region of Fra Mauro? sunrise I . 104 23= Region of Fra Mauro, sunrise II oeo@eeoe©eoooooo 105 24. Region of Fra MaurOj full moon 000ffl®0 ©®00©0©0©0© ©© 25. Region of Fra Mauro^ sunset ... O © ® O ®00®®®® 0 0 0 26. Carpathian Mountains, sunrise . 108 27. , Carpathian Mountains, sunset .. o©®oeoo®o 109 28. Region of Hansteen ............ e©ee®®ooo©©oeffloo©©o,©p® 110 29. Region southwest of Hansteen ... 'o © o o o o o o o' a ® o o o 111 30. Region of O. Struve ........... 112 , 31. Western reaches of Mare Imbrium . 113 32. Aristarchus plateau and western reaches of Mare Imbrium.................................... 114 33. Aristarchus plateau, sunrise .... 115 34. Aristarchus plateau, high lighting 116 35. Aristarchus plateau, sunset ... 000©0®00®©00s© 00000©0©0© 117 36. Region of W. Bond, sunrise ........................... 118 37. Region of W= Bond, sunset ................ ©• ® ® o o o o o e oo 119 38. Region of J. Herschel..... 'o'eo®6©eoo®oo®©ooo0oeo®o©®®e®o120 39. Parallelism of wrinkle ridges in Mare Tranquillitatis .... 121 viii Plate ■ Page; 40.. The radial system of the. Imbr itrm basin .7 .........«... 122 41. Regioti of War gentin from above Mare Orientale . 123 42. Region .southeast of Mare Orientale,*'• sunrise '.»,.,»... *•. ' 124 .43 o . Region southeast of Mare. Orientale, high lighting » , 125 44 . Large-scale., view of Schickard and vicinity'-». „ ,.. 126 40.. Region northeast of Mare Orientale ...»........ 127 - 46. The Orientale. Basin System.......... ............, 128 47. Region south-southeast of Mare Nectar is, sunset I ...... 129 48. Region south-southeast of Mare. Nectar is, sunrise ... 130 49. R egion south-southeast of Mar e Nectar is, , sunset II ..... 131 50. Limb r egion east-southeast of Mar e Nectar is, sunr ise .. 132 51. Region east-southeast of Mare Neetaris, sunset «. L..... 133 52. The Neetaris .Basin. System u ......... 134 53. Region southeast of the Mare Humorum ................. 135 54. Orthogonal lineament pattern west of Mare Humorum, sunrise ...................... 136 55. Orthogonal lineament pattern west of Mar 6: Humorum, sunset................ o...-......................... " 137 56. The Humorum Basin.System .......................... 138 57. Lineaments northwest of Mare Crisium ................ 139 58. Mare Grisium at sunrise ............................. 140 . 59., The-Crisium Basin.System ... 141 60. Region of Mare Humboldfianum ...................... 142 ix . Plate Page 61. ■Region of Mare Huraboldtianum? sunset ,.............. 143 62* Radial systems around crater ss showing Aristillus and Bullialdus oo... oos.oo a a... • a ... ooooo o.oo. oo.ooo.. 144 63* Radial systems around craters, showing Copernicus, EratoStheneSg and Ar istar chus .................... 145 64. Comparison of valleys and troughs of radial system s ..... 146 65. Comparison of orthogonal lineaments (a, b# and c), scarps (dg e, and f), and deformed craters (g, h2 and i) of radial systems ............ ................. 147 66. Schematic diagram of lunar history ..... — ............ 148 ' 67. The lunar basin systems ............................... 149 ABSTRACT Most of the circular maria on the moon occupy structural ba­ sins surrounded by concentric mountainous arcs and radial lineament systems® Most basin systems are.discussed in detail here, and the structures are illustrated with numerous photographSo, Some remarks are made on the small radial systems around some recent craters and on the nonradial grid patterns® The radial systems of the oldest basins ar e the least well de­ veloped. The young basins of Mare Imbrium and Mare Orientale have the most prominent radial systems® ; The lineaments vary greatly in age, but conditions for producing them were probably optimum during the relatively short period when the maria were laid down. Many are spatially related to this flooding. The basins are pr obably the sites of great impacts, accom­ panied by radiating fractur es. Most lineaments are interpreted as the expression of tectonic adjustments in the stressed crust along these fractures as a result of heating of the subsurface. Most of the adjust­ ment is by vertical motion and destruction by flooding. There is little evidence for horizontal motion or for gouging of radial valleys by flying fragments® . x . INTRODUCTION As long ago as the 1890s s it was recognized that at least one ©f the lunar maria is accompanied by a family of radiating surface struc­ tures, Gilbert (1893) described the Imbrium system in a paper which discusses the ’’Imbrium sculpture, ” Most of the discussion: of such ra­ dial structures has concentrated on the array in the region from the Haemus Mountains to Ptolemaeus, radiating
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