大陆碎片

大陆碎片(英语:continental fragment),与微大陆(英语:microcontinent)同义[1]。是从主要大陆块分裂出来形成不同岛屿的大陆片断,通常距其起源地数百公里[2]。大陆碎片包括一些海山和水下高原。

一些微大陆是冈瓦纳或其他古代克拉通大陆的碎片;一些例子包括马达加斯加及北部的马斯卡林高原(Mascarene Plateau),包括塞舌尔(Seychelles)微大陆;和帝汶岛[2]。其他岛屿,例如加勒比海的几个岛屿,也主要由花岗岩组成。在这种定义下岛屿和微大陆之间没有明确的分界线。凯尔盖朗高原(Kerguelen Plateau)是一个由火山热点形成的大型火成岩区域;然而,它与冈瓦纳大陆的解体有关,并且有一段时间在水面之上,因此它被认为是一个微大陆,尽管不是大陆碎片[3][4]

冰岛夏威夷等其他热点岛屿既不被视为微大陆,也不被视为大陆碎片。并非所有岛屿都可以被视为微大陆:例如,不列颠群岛斯里兰卡婆罗洲和纽芬兰都位于相邻大陆的大陆架内,被内陆海淹没其边缘与大陆隔开[5]

参考文献

  1. ^ Microcontinent" was initially the broader term, because it was defined morphologically rather than genetically (in term or genesis or origin). Scrutton, Roger A. (1976) "Microcontinents and Their Significance" pp. 177–189 In Drake, Charles L. (1976) (editor) Geodynamics: Progress and Prospects American Geophysical Union, Washington, D.C., ISBN 978-0-87590-203-6. But, using Scrutton's definition, "microcontinent" is a narrower term, excluding aseismic ridges of continental material, such as the Lomonosov Ridge and the Jan Mayen Ridge, which could still be considered "continental fragments"
  2. ^ 2.0 2.1 Monk, K.A.; Fretes, Y.; Reksodiharjo-Lilley, G. (1996). The Ecology of Nusa Tenggara and Maluku. Hong Kong: Periplus Editions Ltd. pp. 41–43. ISBN 978-962-593-076-3
  3. ^ UT Austin scientist plays major rule in study of underwater "micro-continent". Retrieved on 2007-07-03
  4. ^ Sci/Tech 'Lost continent' discovered Retrieved on 2007-07-03
  5. ^ Péron-Pinvidic, Gwenn; Manatschal, Gianreto (2010). "From microcontinents to extensional allochthons: witnesses of how continents rift and break apart?". Petroleum Geoscience. 16 (3): 189–197. ISSN 1354-0793