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被动大陆边缘张裂形成过程中,在陆缘两侧很容易形成共轭型大陆边缘。大西洋两侧的西非和南美便是典型的例子,由于具有共轭的成因演化,因而具有相似的油气成藏条件。受此启示,推测东非大陆边缘也是在东西冈瓦纳大陆裂解背景下形成的,也应该发育类似大西洋共轭型大陆边缘。通过研究东非构造演化,东非海岸北段—孤岛区具备共轭型大陆边缘的特性,两侧均经历了早期裂谷和晚期被动陆缘的沉积和构造演化,油气地质条件十分相似,勘探成效也证实它们是东非大陆边缘油气最富集的区域。但共轭两侧油气类型差异较大,东非海岸北段以天然气为主,孤岛区则以稠油沥青为主,初步研究认为后期构造的改造和破坏作用直接导致了东非共轭型大陆边缘油气成藏的差异。
Passive continent edge of the crack formation process, both sides of the continental margin is easy to form conjugate continental margin. Typical examples are West and South America on both sides of the Atlantic, which have similar hydrocarbon accumulation conditions due to their conjugate evolution. Based on this revelation, it is speculated that the margins of the East African continent are also formed under the background of the dissolution of the East-West Gondwanaland continent, and a similar Atlantic margin should be developed. By studying the tectonic evolution of the East African continent, the northern part of the East African coast has the characteristics of conjugate continental margins. Both sides experienced sedimentation and tectonic evolution of the early rifting and the late passive continental margin. The geological conditions of oil and gas are very similar, Confirmed that they are the most abundant oil and gas on the margins of the East African continent. However, the types of oil and gas on both sides of the conjugate are quite different. Natural gas is dominant in the northern part of East Africa coast and heavy oil bitumen is mainly located in the island area. Preliminary studies suggest that the remolding and destructive effects of the later structures directly lead to the unconformity of East African conjugate continental margins Differences in accumulation.