Differences in Petroleum Geological Conditions of ConjugateContinental Margin in East Africa
Received date: 2013-06-03
Revised date: 2013-08-05
Online published: 2014-05-10
When passive continental margin extends to both sides,it is easy to form conjugate continental margin.On both sides of the Atlantic Ocean in the West Africa and South America is a typical example.Due to the conjugate evolution,continental margin usually has similar petroleum geological conditions.Based on this,East Africa continental margin,under the background of breakup of East and West Gondwana,should also be similar to the Atlantic conjugate type of continental margin.However,because of no consistent breakup time between the plates,the conjugate characteristics are not obvious and were not discussed in the past.By studying tectonic evolution in East Africa,the northern section of coastal East Africa and islands areas have features of conjugate type of continental margin.Both sides underwent the tectonic evolution of early rifting and late passive continental margin and have similar petroleum geological conditions.Exploration results have confirmed that they are the most enrichment of oil and gas regions in East Africa continental margin.However,conjugated hydrocarbon type has differences on both sides.The northern section of coastal East Africa is dominated by natural gas,while islands areas are mainly heavy oil or tar.Preliminary research suggests that the late period tectonic transformation and damage led directly to the differences among the conjugated hydrocarbon accumulation.
XU Zhi-gang,HAN Wen-ming,SUN Yu-mei . Differences in Petroleum Geological Conditions of ConjugateContinental Margin in East Africa[J]. Natural Gas Geoscience, 2014 , 25(5) : 732 -738 . DOI: 10.11764/j.issn.1672-1926.2014.05.732
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