在被动大陆边缘盆地,水道作为深水油气的主要储集体,是深水油气勘探的重要目标.在下刚果盆地,由于盐构造的多期活动导致对水道砂体的展布规律认识不清.研究水道和盐构造的交互作用方式有利于预测含盐盆地中水道砂体的平面分布.利用三维地震资料,在盐构造与深水水道广泛发育的下刚果盆地研究盐构造与深水水道的交互作用,建立了盐构造与水道的交互作用模式.盐构造与水道的交互作用方式主要有6种,分别为限制、改向、封堵、侵蚀、迁移和剥蚀.盐构造的活动时期与水道形成演化时期的先后关系、水道中重力流的侵蚀能力决定了盐构造与水道的交互作用方式.水道经过早期发育的盐构造且水道中重力流侵蚀能力较弱多发生限制和改向;若水道中重力流侵蚀能力很强,可发生水道对盐构造的侵蚀;若盐构造的规模较大,其可阻止水道向下游输送沉积物并造成水道中重力流的回流,形成朵体沉积.若水道与盐构造同时活动多发生水道的迁移.晚期活动的盐构造可导致其上方的水道沉积体遭受剥蚀.%Submarine channels as the main reservoir of deep-water oil and gas is an important goal of deep-water oil and gas exploration in passive continental margin basin. The multi-periodic tectonic activities of the salt structures re-sult in being not clear about the distribution law of channel sand body in the Lower Congo Basin. The research on in-teractions between submarine channels and salt structures contributes to predict the distribution of channel sand body. In salt structures and submarine channels widely developed area of Lower Congo Basin, based on three-dimensional seismic data, the interactions between salt structures and submarine channels are analyzed and build the interaction model of salt structures related to submarine channels is established. Six submarine channels-salt structures interac-tions can be defined, respectively, as confinement, diversion, blocking, corrosion, deflection, and erosion. The in-teractions between channels and salt structures may be dictated by the timing of salt structural activities related to the channel development and the erosional power of the channels. Salt structures which predate the channel development and the weak erosional power of the flows within the submarine channels cause channels to take a moderate confine-ment or diversion. When the erosional power of the flows is strong enough, submarine channels can continue to incise across the salt structures. The large-scale salt structures can block the submarine channels causing reflection of turbid-ity alone the submarine channel, and lobes develop. Activities of the salt structures which are consistent with channels development may cause deflection. Overlying submarine channels which predate salt structures may be eroded.
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