From csql to csq5 , the barrier system was the main system . from psql to psq5 , the carbonate ramp was the main system and from psq6 to psq8 the main system was fluvial and fluvial - delta system in brackish basin . from psq9 - psql2 , the main system turned to the fluvial - delta system 晚石炭世csq1 ? csq5層序以碎屑海岸障壁?瀉湖和碳酸鹽緩坡沉積體系為主;早二疊世早期psq1 ? psq5層序以碳酸鹽緩坡沉積體系為主,早二疊世晚期psq6 ? psq8層序以半咸水盆地河流、河流三角洲沉積體系為主;中二疊世psq9 ? psq12為陸相沖積扇、河流、湖泊三角洲沉積體系。