Can the terrain of Lanzhou be regarded as a valley? Can it be regarded as a basin?

Lanzhou city is located in the Yellow River basin on the northeast side of the Qinghai-Tibet Plateau, surrounded by mountains. The elevation of the city center is about 1520m, and the relative height of the north and south mountains is 600m·m m. The Yellow River runs through the city from west to east, forming a belt-shaped dumbbell-shaped valley basin with a length of about 35km from east to west and a width of about 2 ~ 8 km from north to south.