A sequence of soils of about the same age, derived from similar parent material and occurring under similar climatic conditions, but having different characteristic due to variation in relief and drainage is called

A sequence of soils of about the same age, derived from similar parent material, occurring under similar parent material and occurring under similar climatic conditions, but having different characteristics due to variation in relief and drainage is called Catena.
The term catena was first coined by scientist Geoffrey Milne to describe these soil-topography units. A mature catena is in equilibrium as the processes of deposition and erosion are in balance.