Because of Yizheng orogeny in Late Cretaceous, braided delta system of Anfeng was formed by rifling in Subei Basin and rising of sedimentary base level.

• 摘要受晚白垩世仪征运动的影响，苏北盆地拉张断陷，沉积基准面上升，从而形成了比较完整的安丰退积型辫状三角洲沉积体系。