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  5.     <title>UTas ePrints - 120 to 0 Ma tectonic evolution of the southwest Pacific and analogous geological evolution of the 600 to 220 Ma Tasman Fold Belt System</title>
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  13.     <meta content="Crawford, A.J." name="eprints.creators_name" />
  14. <meta content="Meffre, S." name="eprints.creators_name" />
  15. <meta content="Symonds, P.A." name="eprints.creators_name" />
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  20. <meta content="2007-02-14" name="eprints.datestamp" />
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  23. <meta content="120 to 0 Ma tectonic evolution of the
  24. southwest Pacific and analogous geological evolution
  25. of the 600 to 220 Ma Tasman Fold Belt System" name="eprints.title" />
  26. <meta content="pub" name="eprints.ispublished" />
  27. <meta content="260100" name="eprints.subjects" />
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  29. <meta content="Australia, Lachlan Fold Belt, southwest Pacific, subduction, Tasman Fold Belt, tectonics" name="eprints.keywords" />
  30. <meta content="We review the tectonic evolution of the SW Pacific east of Australia from ca 120 Ma until the present. A
  31. key factor that developed early in this interval and played a major role in the subsequent geodynamic
  32. history of this region was the calving off from eastern Australia of several elongate microcontinental ribbons,
  33. including the Lord Howe Rise and Norfolk-New Caledonia Ridge. These microcontinental ribbons
  34. were isolated from Australia and from each other during a protracted extension episode from ca 120 to
  35. 52 Ma, with oceanic crust accretion occurring from 85 to 52 Ma and producing the Tasman Sea and
  36. the South Loyalty Basin. Generation of these microcontinental ribbons and intervening basins was
  37. assisted by emplacement of a major mantle plume at 100 Ma beneath the southern part of the Lord
  38. Howe Rise, which in turn contributed to rapid and efficient eastward trench rollback. A major change
  39. in Pacific plate motion at ca 55 Ma initiated east-directed subduction along the recently extinct spreading
  40. centre in the South Loyalty Basin, generating boninitic lithosphere along probably more than 1000
  41. km of plate boundary in this region, and growth of the Loyalty-Entrecasteaux arc. Continued subduction
  42. of South Loyalty Basin crust led to the arrival at about 38 Ma of the 70-60 million years old western
  43. volcanic passive margin of the Norfolk Ridge at the trench, and west-directed emplacement of the
  44. New Caledonia ophiolite. Lowermost allochthons of this ophiolite are Maastrichtian and Paleocene rift
  45. tholeiites derived from the underthrusting passive margin. Higher allochthonous sheets include a poorly
  46. exposed boninitic lava slice, which itself was overridden by the massive ultramafic sheets that cover
  47. large parts of New Caledonia and are derived from the colliding forearc of the Loyalty-Entrecasteaux
  48. arc. Post-collisional extensional tectonism exhumed the underthrust passive margin, parts of which have
  49. blueschist and eclogite facies metamorphic assemblages. Following locking of this subduction zone at
  50. 38-34 Ma, subduction jumped eastward, to form a new west-dipping subduction zone above which
  51. formed the Vitiaz arc, that contained elements which today are located in the Tongan, Fijian, Vanuatu
  52. and Solomons arcs. Several episodes of arc splitting fragmented the Vitiaz arc and produced first the
  53. South Fiji Basin (31-25 Ma) and later (10 Ma to present) the North Fiji Basin. Collision of the Ontong Java
  54. Plateau, a large igneous province, with the Solomons section of the Vitiaz arc resulted in a reversal of
  55. subduction polarity, and growth of the Vanuatu arc on clockwise-rotating, older Vitiaz arc and South Fiji
  56. Basin crust. Continued rollback of the trench fronting the Tongan arc since 6 Ma has split this arc and
  57. produced the Lau Basin-Havre Trough.
  58. This southwest Pacific style of crustal growth above a rolling-back slab is applied to the 600-220 Ma
  59. tectonic development of the Tasman Fold Belt System in southeastern Australia, and explains key
  60. aspects of the geological evolution of eastern Australia. In particular, collision between a plume-triggered
  61. 600 Ma volcanic passive margin and a 510-515 Ma boninitic forearc of an intra-oceanic arc had
  62. the same relative orientation and geological effects as that which produced New Caledonia. A new
  63. subduction system formed probably at least several hundred kilometres east of the collision zone and
  64. produced the Macquarie arc, in which the oldest lavas were erupted ca 480 Ma. Continued slab rollback
  65. induced regional extension and the growth of narrow linear troughs in the Macquarie arc, which
  66. persisted until terminal deformation of this fold belt in the late-Middle to Late Devonian. A similar pattern
  67. of tectonic development generated the New England Fold Belt between the Late Devonian and Late
  68. Triassic. Parts of the New England Fold Belt have been broken from Australia and moved oceanward to
  69. locations in New Zealand, and on the Lord Howe Rise and Norfolk-New Caledonia Rise, during the post-
  70. 120 Ma breakup. Given that the Tasman Fold Belt System grew between 600 and 220 Ma by crustal
  71. accretion like the southwest Pacific since 120 Ma, facing the open Pacific Ocean, we question whether
  72. the eastern (Australia-Antarctica) part of the Neoproterozoic Rodinian supercontinent was joined to
  73. Laurentia." name="eprints.abstract" />
  74. <meta content="2003-10-31" name="eprints.date" />
  75. <meta content="submitted" name="eprints.date_type" />
  76. <meta content="Geological Society of Australia Special Publication" name="eprints.publication" />
  77. <meta content="22" name="eprints.volume" />
  78. <meta content="Geological Society of Australia Special Publication" name="eprints.publisher" />
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  80. <meta content="377-397" name="eprints.pagerange" />
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  83. <meta content="Evolution and Dynamics of the Australian Plate" name="eprints.book_title" />
  84. <meta content="Crawford, A.J. and Meffre, S. and Symonds, P.A. (2003) 120 to 0 Ma tectonic evolution of the southwest Pacific and analogous geological evolution of the 600 to 220 Ma Tasman Fold Belt System. In: Evolution and Dynamics of the Australian Plate. . Geological Society of Australia Special Publication, Australia, pp. 377-397." name="eprints.citation" />
  85. <meta content="http://eprints.utas.edu.au/680/1/Crawford_2003%2C_SW_Pacific.pdf" name="eprints.document_url" />
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  87. <meta content="120 to 0 Ma tectonic evolution of the
  88. southwest Pacific and analogous geological evolution
  89. of the 600 to 220 Ma Tasman Fold Belt System" name="DC.title" />
  90. <meta content="Crawford, A.J." name="DC.creator" />
  91. <meta content="Meffre, S." name="DC.creator" />
  92. <meta content="Symonds, P.A." name="DC.creator" />
  93. <meta content="260100 Geology" name="DC.subject" />
  94. <meta content="We review the tectonic evolution of the SW Pacific east of Australia from ca 120 Ma until the present. A
  95. key factor that developed early in this interval and played a major role in the subsequent geodynamic
  96. history of this region was the calving off from eastern Australia of several elongate microcontinental ribbons,
  97. including the Lord Howe Rise and Norfolk-New Caledonia Ridge. These microcontinental ribbons
  98. were isolated from Australia and from each other during a protracted extension episode from ca 120 to
  99. 52 Ma, with oceanic crust accretion occurring from 85 to 52 Ma and producing the Tasman Sea and
  100. the South Loyalty Basin. Generation of these microcontinental ribbons and intervening basins was
  101. assisted by emplacement of a major mantle plume at 100 Ma beneath the southern part of the Lord
  102. Howe Rise, which in turn contributed to rapid and efficient eastward trench rollback. A major change
  103. in Pacific plate motion at ca 55 Ma initiated east-directed subduction along the recently extinct spreading
  104. centre in the South Loyalty Basin, generating boninitic lithosphere along probably more than 1000
  105. km of plate boundary in this region, and growth of the Loyalty-Entrecasteaux arc. Continued subduction
  106. of South Loyalty Basin crust led to the arrival at about 38 Ma of the 70-60 million years old western
  107. volcanic passive margin of the Norfolk Ridge at the trench, and west-directed emplacement of the
  108. New Caledonia ophiolite. Lowermost allochthons of this ophiolite are Maastrichtian and Paleocene rift
  109. tholeiites derived from the underthrusting passive margin. Higher allochthonous sheets include a poorly
  110. exposed boninitic lava slice, which itself was overridden by the massive ultramafic sheets that cover
  111. large parts of New Caledonia and are derived from the colliding forearc of the Loyalty-Entrecasteaux
  112. arc. Post-collisional extensional tectonism exhumed the underthrust passive margin, parts of which have
  113. blueschist and eclogite facies metamorphic assemblages. Following locking of this subduction zone at
  114. 38-34 Ma, subduction jumped eastward, to form a new west-dipping subduction zone above which
  115. formed the Vitiaz arc, that contained elements which today are located in the Tongan, Fijian, Vanuatu
  116. and Solomons arcs. Several episodes of arc splitting fragmented the Vitiaz arc and produced first the
  117. South Fiji Basin (31-25 Ma) and later (10 Ma to present) the North Fiji Basin. Collision of the Ontong Java
  118. Plateau, a large igneous province, with the Solomons section of the Vitiaz arc resulted in a reversal of
  119. subduction polarity, and growth of the Vanuatu arc on clockwise-rotating, older Vitiaz arc and South Fiji
  120. Basin crust. Continued rollback of the trench fronting the Tongan arc since 6 Ma has split this arc and
  121. produced the Lau Basin-Havre Trough.
  122. This southwest Pacific style of crustal growth above a rolling-back slab is applied to the 600-220 Ma
  123. tectonic development of the Tasman Fold Belt System in southeastern Australia, and explains key
  124. aspects of the geological evolution of eastern Australia. In particular, collision between a plume-triggered
  125. 600 Ma volcanic passive margin and a 510-515 Ma boninitic forearc of an intra-oceanic arc had
  126. the same relative orientation and geological effects as that which produced New Caledonia. A new
  127. subduction system formed probably at least several hundred kilometres east of the collision zone and
  128. produced the Macquarie arc, in which the oldest lavas were erupted ca 480 Ma. Continued slab rollback
  129. induced regional extension and the growth of narrow linear troughs in the Macquarie arc, which
  130. persisted until terminal deformation of this fold belt in the late-Middle to Late Devonian. A similar pattern
  131. of tectonic development generated the New England Fold Belt between the Late Devonian and Late
  132. Triassic. Parts of the New England Fold Belt have been broken from Australia and moved oceanward to
  133. locations in New Zealand, and on the Lord Howe Rise and Norfolk-New Caledonia Rise, during the post-
  134. 120 Ma breakup. Given that the Tasman Fold Belt System grew between 600 and 220 Ma by crustal
  135. accretion like the southwest Pacific since 120 Ma, facing the open Pacific Ocean, we question whether
  136. the eastern (Australia-Antarctica) part of the Neoproterozoic Rodinian supercontinent was joined to
  137. Laurentia." name="DC.description" />
  138. <meta content="Geological Society of Australia Special Publication" name="DC.publisher" />
  139. <meta content="2003-10-31" name="DC.date" />
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  144. <meta content="Crawford, A.J. and Meffre, S. and Symonds, P.A. (2003) 120 to 0 Ma tectonic evolution of the southwest Pacific and analogous geological evolution of the 600 to 220 Ma Tasman Fold Belt System. In: Evolution and Dynamics of the Australian Plate. . Geological Society of Australia Special Publication, Australia, pp. 377-397." name="DC.identifier" />
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  251.     <h1 class="ep_tm_pagetitle">120 to 0 Ma tectonic evolution of the southwest Pacific and analogous geological evolution of the 600 to 220 Ma Tasman Fold Belt System</h1>
  252.     <p style="margin-bottom: 1em" class="not_ep_block"><span class="person_name">Crawford, A.J.</span> and <span class="person_name">Meffre, S.</span> and <span class="person_name">Symonds, P.A.</span> (2003) <xhtml:em>120 to 0 Ma tectonic evolution of the southwest Pacific and analogous geological evolution of the 600 to 220 Ma Tasman Fold Belt System.</xhtml:em> In: Evolution and Dynamics of the Australian Plate. . Geological Society of Australia Special Publication, Australia, pp. 377-397.</p><p style="margin-bottom: 1em" class="not_ep_block"></p><table style="margin-bottom: 1em" class="not_ep_block"><tr><td valign="top" style="text-align:center"><a onmouseover="EPJS_ShowPreview( event, 'doc_preview_690' );" onmouseout="EPJS_HidePreview( event, 'doc_preview_690' );" href="http://eprints.utas.edu.au/680/1/Crawford_2003%2C_SW_Pacific.pdf"><img alt="[img]" src="http://eprints.utas.edu.au/style/images/fileicons/application_pdf.png" border="0" class="ep_doc_icon" /></a><div class="ep_preview" id="doc_preview_690"><table><tr><td><img alt="" src="http://eprints.utas.edu.au/680/thumbnails/1/preview.png" border="0" class="ep_preview_image" /><div class="ep_preview_title">Preview</div></td></tr></table></div></td><td valign="top"><a href="http://eprints.utas.edu.au/680/1/Crawford_2003%2C_SW_Pacific.pdf"><span class="ep_document_citation">PDF</span></a> - Requires a PDF viewer<br />2450Kb</td></tr></table><div class="not_ep_block"><h2>Abstract</h2><p style="padding-bottom: 16px; text-align: left; margin: 1em auto 0em auto">We review the tectonic evolution of the SW Pacific east of Australia from ca 120 Ma until the present. A&#13;
  253. key factor that developed early in this interval and played a major role in the subsequent geodynamic&#13;
  254. history of this region was the calving off from eastern Australia of several elongate microcontinental ribbons,&#13;
  255. including the Lord Howe Rise and Norfolk-New Caledonia Ridge. These microcontinental ribbons&#13;
  256. were isolated from Australia and from each other during a protracted extension episode from ca 120 to&#13;
  257. 52 Ma, with oceanic crust accretion occurring from 85 to 52 Ma and producing the Tasman Sea and&#13;
  258. the South Loyalty Basin. Generation of these microcontinental ribbons and intervening basins was&#13;
  259. assisted by emplacement of a major mantle plume at 100 Ma beneath the southern part of the Lord&#13;
  260. Howe Rise, which in turn contributed to rapid and efficient eastward trench rollback. A major change&#13;
  261. in Pacific plate motion at ca 55 Ma initiated east-directed subduction along the recently extinct spreading&#13;
  262. centre in the South Loyalty Basin, generating boninitic lithosphere along probably more than 1000&#13;
  263. km of plate boundary in this region, and growth of the Loyalty-Entrecasteaux arc. Continued subduction&#13;
  264. of South Loyalty Basin crust led to the arrival at about 38 Ma of the 70-60 million years old western&#13;
  265. volcanic passive margin of the Norfolk Ridge at the trench, and west-directed emplacement of the&#13;
  266. New Caledonia ophiolite. Lowermost allochthons of this ophiolite are Maastrichtian and Paleocene rift&#13;
  267. tholeiites derived from the underthrusting passive margin. Higher allochthonous sheets include a poorly&#13;
  268. exposed boninitic lava slice, which itself was overridden by the massive ultramafic sheets that cover&#13;
  269. large parts of New Caledonia and are derived from the colliding forearc of the Loyalty-Entrecasteaux&#13;
  270. arc. Post-collisional extensional tectonism exhumed the underthrust passive margin, parts of which have&#13;
  271. blueschist and eclogite facies metamorphic assemblages. Following locking of this subduction zone at&#13;
  272. 38-34 Ma, subduction jumped eastward, to form a new west-dipping subduction zone above which&#13;
  273. formed the Vitiaz arc, that contained elements which today are located in the Tongan, Fijian, Vanuatu&#13;
  274. and Solomons arcs. Several episodes of arc splitting fragmented the Vitiaz arc and produced first the&#13;
  275. South Fiji Basin (31-25 Ma) and later (10 Ma to present) the North Fiji Basin. Collision of the Ontong Java&#13;
  276. Plateau, a large igneous province, with the Solomons section of the Vitiaz arc resulted in a reversal of&#13;
  277. subduction polarity, and growth of the Vanuatu arc on clockwise-rotating, older Vitiaz arc and South Fiji&#13;
  278. Basin crust. Continued rollback of the trench fronting the Tongan arc since 6 Ma has split this arc and&#13;
  279. produced the Lau Basin-Havre Trough.&#13;
  280. This southwest Pacific style of crustal growth above a rolling-back slab is applied to the 600-220 Ma&#13;
  281. tectonic development of the Tasman Fold Belt System in southeastern Australia, and explains key&#13;
  282. aspects of the geological evolution of eastern Australia. In particular, collision between a plume-triggered&#13;
  283. 600 Ma volcanic passive margin and a 510-515 Ma boninitic forearc of an intra-oceanic arc had&#13;
  284. the same relative orientation and geological effects as that which produced New Caledonia. A new&#13;
  285. subduction system formed probably at least several hundred kilometres east of the collision zone and&#13;
  286. produced the Macquarie arc, in which the oldest lavas were erupted ca 480 Ma. Continued slab rollback&#13;
  287. induced regional extension and the growth of narrow linear troughs in the Macquarie arc, which&#13;
  288. persisted until terminal deformation of this fold belt in the late-Middle to Late Devonian. A similar pattern&#13;
  289. of tectonic development generated the New England Fold Belt between the Late Devonian and Late&#13;
  290. Triassic. Parts of the New England Fold Belt have been broken from Australia and moved oceanward to&#13;
  291. locations in New Zealand, and on the Lord Howe Rise and Norfolk-New Caledonia Rise, during the post-&#13;
  292. 120 Ma breakup. Given that the Tasman Fold Belt System grew between 600 and 220 Ma by crustal&#13;
  293. accretion like the southwest Pacific since 120 Ma, facing the open Pacific Ocean, we question whether&#13;
  294. the eastern (Australia-Antarctica) part of the Neoproterozoic Rodinian supercontinent was joined to&#13;
  295. Laurentia.</p></div><table style="margin-bottom: 1em" border="0" cellpadding="3" class="not_ep_block"><tr><th valign="top" class="ep_row">Item Type:</th><td valign="top" class="ep_row">Book Chapter</td></tr><tr><th valign="top" class="ep_row">Keywords:</th><td valign="top" class="ep_row">Australia, Lachlan Fold Belt, southwest Pacific, subduction, Tasman Fold Belt, tectonics</td></tr><tr><th valign="top" class="ep_row">Subjects:</th><td valign="top" class="ep_row"><a href="http://eprints.utas.edu.au/view/subjects/260100.html">260000 Earth Sciences &gt; 260100 Geology</a></td></tr><tr><th valign="top" class="ep_row">Collections:</th><td valign="top" class="ep_row">UNSPECIFIED</td></tr><tr><th valign="top" class="ep_row">ID Code:</th><td valign="top" class="ep_row">680</td></tr><tr><th valign="top" class="ep_row">Deposited By:</th><td valign="top" class="ep_row"><span class="ep_name_citation"><span class="person_name">Mr Ruben Chan</span></span></td></tr><tr><th valign="top" class="ep_row">Deposited On:</th><td valign="top" class="ep_row">14 Feb 2007</td></tr><tr><th valign="top" class="ep_row">Last Modified:</th><td valign="top" class="ep_row">30 Jan 2008 15:50</td></tr><tr><th valign="top" class="ep_row">ePrint Statistics:</th><td valign="top" class="ep_row"><a target="ePrintStats" href="/es/index.php?action=show_detail_eprint;id=680;">View statistics for this ePrint</a></td></tr></table><p align="right">Repository Staff Only: <a href="http://eprints.utas.edu.au/cgi/users/home?screen=EPrint::View&amp;eprintid=680">item control page</a></p>
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