The Mashan Group is the basement of Jiamusi Massif, whereas the Heilongjiang Group represents an accretionary-collision complex containing remnants of oceanic crust.

• 穆棱地区的“麻山群”为佳木斯地块南缘的陆壳基底，其南侧的“黑龙江群”为包括洋壳残片在内的增生-碰撞杂岩。