What does the blue axis diagram of Chengjiang show?

There is an oasis surrounded by turquoise on the river bank, with slender trees, houses like beans, pavilions with peaks and clouds.

Blue Cave Map of Chengjiang in Song Dynasty. Silk books are collected in Shanghai Museum, with a length of 23.8 cm and a width of 26.3 cm. In a short-sized picture, many scenes are concentrated in a small corner on the left, with a compact layout but great momentum. In terms of pen and ink techniques, it has the style of green mountains and rivers in the Tang Dynasty. The shapes of rocks are mostly hook-shaped, and then they are filled with stone green, flower green and ochre to express different textures and light feelings, which has a strong decorative meaning. However, the traces of brush strokes show that the vast blank space is a vast river. The whole painting still has a strong style of the times in composition and conception, and it is a fascinating masterpiece.