Pattern analysis and dating for the Badain Jaran dune field, northwestern China

Pattern analysis can estimate dune formation ages, judge wind conditions and extract environmental signals from the common pattern parameters of active dune field. For the extraterrestrial dune fields, this method is a great advantage while many in situ and laboratory techniques cannot do anything. An ideal location for the large-scale pattern analysis test is the Badain Jaran desert where the tallest terrestrial aeolian dune occurs. In this study, the function forms of pattern parameters varying with the dune construction time are established, according to the natural evolution of a dune field in the duration of over 10 years. It is revealed that the relations between pattern parameters and time display power functions, in which the unknown coefficients in different conditions of wind regimes and sand availabilities can be estimated from the absolute ages of local deposits. From the northwest to southeast of the Badain Jaran desert, the dune crest length and mean spacing increase, and the defect density decreases. The pattern ages change correspondingly. Dune orientation mostly ranges between 10 ∘ and 60 ∘ . The crest length ages indicate that the modern active dune field began to form at about 20–75 ka BP, the dunes in the southeast and northeast are older than those in the western. This work confirms that pattern analysis offers an effective dating method for hard-to-reach or large-scale dune fields.