¿Por qué las columnas de piedra de Zhangjiajie parecen haber sido barbudas por cuchillos y hachas?

These stone pillars are made of 300-million-year-old quartz sandstone. After tectonic uplift lifted them upward, prolonged erosion by rainwater and rivers carved out vertical joints, making them appear as if sculpted by nature's precise "carving tools." The most iconic example, the "Avatar Hallelujah Mountain" (Qiankun Column), even inspired the floating mountains in the movie Avatar!