地势自西北向东南阶梯下降，北部为内蒙古高原的东南边缘，中部为浅山区，南部为燕山山脉。

Terrain from the northwest to the southeast steps down, to the north is the southeastern edge of the Inner Mongolia plateau, the central is the lower mountain area, the south is the Yanshan mountains.

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油源对比表明，上二叠统优质烃源岩主要分布于达坂城次凹东北部，其生成的油气沿燕山、喜山期形成的断裂以及上二叠统孔、渗性较好的输导层向西南方向斜坡带的较高部位运移。

Oil and gas generated in the northeastmoved to the southwest, the higher part of the slope through fault and permeable carrier layer, and accumulated in the favorable place of strata and structure.

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