The intracratonic Irumide Belt of Zambia and its bearing on collision orogeny during the Proterozoic of Africa
The intracratonic Irumide Belt of Zambia and its bearing on collision orogeny during the Proterozoic of Africa
复制标题
赞比亚克拉通内伊鲁米德带及其对非洲元古代碰撞造山运动的影响
DOI：
10.1144/gsl.sp.1986.019.01.18
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
M. Daly
中科院分区：
文献类型：
--
作者：
M. Daly
赞比亚的伊鲁米德带经常被认为是典型的非洲克拉通内活动带，它不涉及地壳缩短或大位移。这里显示的这一带包括北西向的前陆褶皱和南莫拉蒂格带的逆冲带，并涉及到相当大的地壳缩短。地壳规模的“弹跳”构造将该前陆与马拉维和莫桑比克的内部高品位麻粒岩相岩石分开，在那里描述了Irumide时代的主要面向东南的推覆构造。确定了几个可能的缝合带，并解释了中元古代碰撞作用的结果。邻近的乌本底带是一个与伊鲁米德带地壳缩短有关的大陆转换断裂带。简要讨论了这些解释对元古宙和太古宙板块构造发生的意义。
Summary The Irumide Belt of Zambia is often quoted as being typical of African intracratonic mobile belts which involve no crustal shortening or major displacements. This belt is shown here to include the NW-facing foreland fold and thrust zone of the Southern Moçambique Belt and to have involved considerable crustal shortening. A crustal scale ‘pop-up’ structure separates this foreland from the internal higher-grade granulite-facies rocks of Malawi and Moçambique where major SE-facing nappe structures of Irumide age have been described. Several possible suture zones are identified and the Irumide-Moçambique Belt is interpreted as resulting from collisional processes during the Mid-Proterozoic. The adjacent Ubendian Belt represents a continental transform fault zone associated with crustal shortening across the Irumide Belt. The implications of these interpretations regarding the onset of plate tectonics in the Proterozoic and Archaean are briefly discussed.