大陸碎片(英語:continental fragment),與微大陸(英語:microcontinent)同義[1]。是從主要大陸塊分裂出來形成不同島嶼的大陸片斷,通常距其起源地數百公里[2]。大陸碎片包括一些海山和水下高原。

一些微大陸是岡瓦納或其他古代克拉通大陸的碎片;一些例子包括馬達加斯加及北部的馬斯卡林高原(Mascarene Plateau),包括塞舌爾(Seychelles)微大陸;和帝汶島[2]。其他島嶼,例如加勒比海的幾個島嶼,也主要由花崗岩組成。在這種定義下島嶼和微大陸之間沒有明確的分界線。凱爾蓋朗高原(Kerguelen Plateau)是一個由火山熱點形成的大型火成岩區域;然而,它與岡瓦納大陸的解體有關,並且有一段時間在水面之上,因此它被認為是一個微大陸,儘管不是大陸碎片[3][4]

冰島夏威夷等其他熱點島嶼既不被視為微大陸,也不被視為大陸碎片。並非所有島嶼都可以被視為微大陸:例如,不列顛群島斯里蘭卡婆羅洲和紐芬蘭都位於相鄰大陸的大陸架內,被內陸海淹沒其邊緣與大陸隔開[5]

參考文獻 编辑

  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