On the influence of global change of Cenozoic climate and uplift of Himalayas, the area began to present a distinct seasonal climate on the basis of previous warmth and humidity in Pliocene.

• 受新生代全球气候变冷和喜马拉雅运动的影响，该盆地一方面受印度洋季风的影响增强，干湿季节交替明显；另一方面受地形地貌影响，沿袭了温暖湿润的气候条件。