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SELF-ORGANIZED BREAKUP OF GONDWANA by JIM SEARS UNIVERSITY OF MONTANA MAIN CONCLUSIONS: BREAKUP OF GONDWANA WAS SELF-ORG

SELF-ORGANIZED BREAKUP OF GONDWANA by JIM SEARS UNIVERSITY OF MONTANA MAIN CONCLUSIONS: BREAKUP OF GONDWANA WAS SELF-ORGANIZED TO MINIMIZE WORK ARGUES AGAINST DEEP MANTLE PLUMES. HEARD ISLAND HOT SPOT. THE DEEP MANTLE PLUME PARADIGM:

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SELF-ORGANIZED BREAKUP OF GONDWANA by JIM SEARS UNIVERSITY OF MONTANA MAIN CONCLUSIONS: BREAKUP OF GONDWANA WAS SELF-ORG

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  1. SELF-ORGANIZED BREAKUP OF GONDWANA • by • JIM SEARS • UNIVERSITY OF MONTANA • MAIN CONCLUSIONS: • BREAKUP OF GONDWANA WAS SELF-ORGANIZED TO MINIMIZE WORK • ARGUES AGAINST DEEP MANTLE PLUMES HEARD ISLAND HOT SPOT

  2. THE DEEP MANTLE PLUME PARADIGM: AN INTEGRAL PART OF PLATE TECTONICS SINCE J.T. WILSON (1963) AND W.J. MORGAN (1981)

  3. STATIONARY HOT SPOT VOLCANOES: TAILS OF DEEP MANTLE PLUMES?

  4. LARGE IGNEOUS PROVINCES (LIPS): HEADS OF DEEP MANTLE PLUMES?

  5. HEADS AND TAILS LINKED BY HOT SPOT TRACKS?

  6. PLUMES RANDOMLY GENERATED AT CORE-MANTLE BOUNDARY? • PLUME OUTBREAKS INITIATE CONTINENTAL BREAKUP?

  7. INDIA GONDWANA AUST AF ANTARCTICA NZ SA

  8. CAMP - FERNANDO ACCEPTED MODEL FOR GONDWANA BREAKUP LAWVER ET AL. 1999 1999 UTIG

  9. KAROO-BOUVET 1999 UTIG

  10. GALLODAI-MARION 1999 UTIG

  11. PARANA-TRISTAN 1999 UTIG

  12. RAJMAHAL-KERGUELEN BANBURY-HEARD 1999 UTIG

  13. HOTSPOT CONSTELLATION 1999 UTIG

  14. ARABIA INDIA AFRICA AUSTRALIA FLORIDA ANTARCTICA SOUTH AMERICA N Z HOWEVER, BREAKUP OF GONDWANA WAS NOT RANDOM - IT WAS HIGHLY SELF-ORGANIZED

  15. ETHIOPIAN 38 Ma DECCAN 65 Ma RAJMAHAL 110 Ma CAMP 205 Ma MARANHAO 200 Ma GALLODAI 144 Ma PARANA 134 Ma KAROO 183 Ma TRANSKEI FERRAR 183 Ma LIMPOBO LARGE IGNEOUS PROVINCES

  16. ST HELENA MARION CROZET KERGUELEN ASCENCION HEARD FERNANDO TRISTAN BOUVET GOUGH GONDWANA HOT SPOT FAMILY

  17. GODAV ARI BENUE TRANSKEI TACUTU PERU-PARAGUAY DISCONTINUITY WEDELL THESE MAJOR GONDWANA FRACTURE POLYGONS RIGOROUSLY OBEY EULER’S THEOREM FOR CONVEX POLYTOPES

  18. GONDWANA NAMELY, TO TILE A SPHERE WITH 12 + PLATES, 12 MUST HAVE 5-FOLD SYMMETRY AT PRECISELY-DEFINED VERTICES OF ICOSAHEDRON

  19. GONDWANA REMAINING (N-12) PLATES HAVE 6-FOLD SYMMETRY

  20. ICOSAHEDRAL ARRANGEMENTS Euler’s formula relating faces (F), vertices (V), and edges (E) of a convex polytope (F + V = E + 2)

  21. ICOSAHEDRAL VIRUS HERPES SIMPLEX

  22. FINITE ELEMENT SOLUTION FOR THOMSON PROBLEM WITH 912 CHARGES ON SPHERE (Altschuler et al., 1997)

  23. GONDWANA EDGE LENGTHS AND CENTERS ARE RIGOROUSLY DEFINED EACH EDGE = 2600 KM AT EARTH SCALE

  24. ANTARCTICA

  25. PENTAGON RIFT EDGES ~ 2600 KM 2600 KM 2600 KM 2600 KM

  26. P GONDWANA H H H P H P H PENTAGONS AND HEXAGONS IN EXACT ARRANGEMENT

  27. P GONDWANA H H H P H P H 16 EDGES, >20,000 KM

  28. GONDWANA PATTERN MINIMIZES TOTAL FRACTURE LENGTH AND THEREFORE MINIMIZES WORK FUNCTION OF STRENGTH OF GONDWANA SHELL STRONGER GONDWANA WEAKER

  29. GONDWANA PATTERN MINIMIZES TOTAL FRACTURE LENGTH AND THEREFORE MINIMIZES WORK FUNCTION OF STRENGTH OF GONDWANA SHELL STRONGER X GONDWANA WEAKER

  30. LARGE IGNEOUS PROVINCES • ERUPTED DIACHRONOUSLY ALONG FRACTURE PATTERN • DEPENDED ON PLATE TECTONICS TO OPEN • FRACTURES TO INDUCE DECOMPRESSION MELTING

  31. CONCORDANCE OF FAMILY OF HOT SPOTS WITH FRACTURE TESSELLATION • SHOWS HOT SPOTS ARE NON-RANDOM

  32. YELLOW STRESS TESSELLATION IS DUAL OF FRACTURE TESSELLATION: THEY CROSS ONE ANOTHER ORTHOGONALLY HOTSPOTS ON TESSELLATION

  33. HOOP STRESS ALONG NORTHERN GONDWANA MARGIN NOTE RADIAL FRACTURES AT MARGIN HOTSPOTS ON TESSELLATION

  34. NOTE PERFECT SYMMETRY OF STRESS TESSELLATION ACROSS GONDWANA HOTSPOTS FAVOR CENTERS HOTSPOTS ON TESSELLATION EXPANSION OF GONDWANA LEADS TO FRACTURES

  35. FRACTURE SYSTEM INDICATES GONDWANA WAS UNDER UNIFORM TENSION

  36. NOTE SYMMETRY OF STRESS TESSELLATION ACROSS GONDWANA HOTSPOTS ON TESSELLATION

  37. INITIAL GEOMETRY OF GONDWANA DETERMINED BEST ORIENTATION OF TESSELLATION TO ACHIEVE MINIMUM FRACTURE LENGTH • AND THEREFORE LEAST WORK

  38. AFRICAN GEOID ANOMALY SYMMETRICAL TO FRACTURES WHEN GONDWANA IS RESTORED TO TRIASSIC POSITION HOTSPOTS ON TESSELLATION

  39. GONDWANA SPREAD OUTWARD DOWN GEOID GRADIENT SEE ANDERSON, 1982 HOTSPOTS ON TESSELLATION

  40. GONDWANA STALLED ON MANTLE FRAMEWORK • INSULATED UNDERLYING MANTLE • THERMAL EXPANSION OF MANTLE DROVE UPLIFT AND UNIFORM TENSION IN GONDWANA • FRACTURE TESSELLATION OCCURRED AT CLIMAX OF UPLIFT, IN EARLY TRIASSIC • FRACTURES LATER SEPARATED AS REQUIRED BY PLATE TECTONICS, DRIVING DECOMPRESSION MELTING

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