南美奥连特前陆盆地斜坡带低幅度构造形成物理模拟

摘要

The Oriente Basin is a back-arc foreland basin, located in front of the Andes in South America.A large number of low-amplitude structures with close relationship to hydrocarbon accumulation are developed in the eastern slope zone of the Oriente Basin.Based on deep analysis of development characteristics and corresponding structural physical simulation, formation process and main controlling factors of the low-amplitude structures are ad-dressed.The results show that the low-amplitude structures in the eastern slope zone of the Oriente Basin are usual-ly accompanied by thrust faults, inversion faults and strike-slip faults.They are generally situated on the hanging walls of these faults.The main dynamic mechanism controlling the development of the low-amplitude structures in-volves inversion and strike-slipping movement of faults.In addition, the pre-exiting normal faults with lower dip an-gle in deep layer have also exerted positive influence on late fault inversion and development of low-amplitude struc-tures.%奥连特盆地是一个位于南美安第斯山前的弧后前陆盆地，盆地东部斜坡带发育大量低幅度构造，并与油气有密切关系。为明确奥连特盆地东部斜坡带低幅度构造的形成过程及其主控因素，深入分析了低幅度构造的发育特征，针对性地开展了构造物理模拟实验研究。结果表明，奥连特盆地东部斜坡带低幅度构造主要与逆断层、反转断层和走滑断层相伴生，一般位于断层上盘，控制其发育的动力学机制主要是断层的正反转作用和走滑作用，而且先存正断层向深部变缓，有利于断层后期的反转以及低幅度构造的发育。