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退积反射是地层厚度向凹陷中心减薄且其顶部被“削截”的一种反射现象 ,与一般发生在凹陷边缘地层顶界被削截减薄的情形不同。陆相盆地中退积反射较少见 ,一般仅出现在湖相沉积中 ,而且只有当湖平面快速长期上升和单一主物源碎屑供应逐渐减少后退 ,引起可容空间大幅度增大时才可形成。它的退覆方向一般指示了单一主物源的方向。在湖相层序地层学中 ,具退积反射地层就是水进体系域 ,顶界即密集段 ,上覆为具前积反射或平行反射的高位体系域。具退积反射的水进体系域往往发生在较大级别的湖面升降旋回 (4～ 10 Ma)中。
Reversed reflections are a reflection phenomenon that the thickness of the formation is thinned toward the center of the depression and the top of the formation is “truncated”, which is different from the situation where the top boundary of the marginal layer of the depression is truncated and thinned. The retrograde reflections are less common in continental basins and generally occur only in lacustrine sediments, and only when the lake level is rapidly and long-term rising and the supply of debris from a single primary source gradually recede, which results in a significant increase in the tolerable space form. Its direction of retirement generally indicates the direction of a single primary source. In the lacustrine sequence stratigraphy, the retrogressive reflection strata are the water-in-system tract, the top boundary is the dense segment, and the overlying strata are high-level system tract with pre-product reflections or parallel reflections. The water with retrograde reflection into the syenograd domain often occurs in the larger level of the lake lift cycle (4 ~ 10 Ma).