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来源：雅诚德英语网
Near NW-SE compressive folding occurred in early Yanshan orogeny, when it began to buckle.
燕山早期运动主要为NW-SE向的挤压褶皱作用，断裂带走向开始弯曲变形；
Near NW-SE compressive folding occurred in early Yanshan orogeny, when it began to buckle.
燕山早期运动主要为NW-SE向的挤压褶皱作用，断裂带走向开始弯曲变形；