非洲Muglad盆地高孔高渗储层成因机制探讨

Mechanism of Forming High Porosity and Permeability Reservoir in Muglad Basin of Africa

从岩石学、地球化学、储层地质学和构造地质学等角度,探讨了非洲中部的Muglad盆地高孔高渗储集层特征.研究表明,Muglad盆地优质储层发育的地质机理在于其独特的沉积构造背景--被动裂谷.在被动裂谷幕式旋回坳陷期相对稳定的构造背景下,沉积了远距离物源的高成熟度砂体,加之超淡的沉积水介质和偏低的地温梯度,形成了Muglad盆地高孔隙度、高渗透率、高石英比和胶结程度相对较弱的区域性优质储集层.

High porosity and permeability characters of reservoirs in Muglad basin of central Africa was researched from the point of view of lithology, geochemistry, reservoir geology, tectonics, and so on. The geological mechanism of high quality reservoir in Muglad basin is due to its particularsedimentary-tectonic background--passive rift. The high matured sandstone of far-forth masssource was deposited in the basin during every steady depression period of passive rifting, which, together with the geological environment of fresh diagenesis water and the lower geothermal degree, resulting in a regional high quality reservoir in Muglad basin with the characters of high porosity, high permeability, high quartz ratio and weak cementation.