Pattern Analysis and Dating for the Badain Jaran Dune Field
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Environmental Earth Sciences (2020) 79:347 https://doi.org/10.1007/s12665-020-09066-4 ORIGINAL ARTICLE Pattern analysis and dating for the Badain Jaran dune feld, northwestern China Wen‑Xiao Ning1,2 · Zhen‑Ting Wang1 Received: 22 May 2019 / Accepted: 17 June 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020 Abstract Pattern analysis can estimate dune formation ages, judge wind conditions and extract environmental signals from the com- mon pattern parameters of active dune feld. For the extraterrestrial dune felds, 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 feld 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 coefcients in diferent 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 feld 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 confrms that pattern analysis ofers an efective dating method for hard-to-reach or large-scale dune felds. Keywords Badain Jaran · Active dune feld · Pattern analysis · Remote sensing · Pattern dating Introduction defect/bedform repulsion and of-centre collision) efects coexist (Kocurek and Ewing 2005; Ewing and Kocurek Nature provides examples of many kinds of pattern, dune 2010a, b). However, the boundary conditions of the system, feld is one of them. Aeolian dune felds that exist in a simple including wind regime and sediment supply, often restrict form, usually exhibit some complexity, such as the nonlinear the external environment conditions of dune interactions, formation process and self-organized aggregation behavior thus afecting the evolution of dune felds. At the same (Werner 1999). Beginning with small and disordered dunes, time, dune felds also contain some important information dune felds gradually become better organized with longer of paleoenvironment and paleoclimate. Since aeolian dune crests and wider spacing, through interactions between felds are composed of diferent spatial scales of bedform bedforms (Sharp 1963; Kocurek et al. 1992; Werner and pattern (Ewing et al. 2015), the analysis of large-scale pat- Gillespie 1993; Werner 1995; Werner and Kocurek 1997, tern parameters can reveal the response of dunes to long- 1999). In fact, in the process of dune collisions, positive (it term atmospheric changes and sedimentary conditions (Fen- makes the pattern more ordered, e.g. merging and lateral ton et al. 2014; Savage et al. 2014). linking), negative (it produces more disorganized system, In recent years, with the improvement of spectral and e.g. defect creation and bedform splitting) and neutral (e.g. spatial resolution of remote sensing data, the study of aeolian sand dunes has gradually shifted from the map- * Wen-Xiao Ning ping and classification of dunes in the early stage to [email protected] quantitative analysis of dune morphological dynamics and dune field pattern analysis, see the review of Hugen- 1 Northwest Institute of Eco-Environment and Resources, holtz et al. (2012) and references therein for details. The CAS, Lanzhou 730000, People’s Republic of China common parameters of dune field patterns, i.e. dune spac- 2 University of Chinese Academy of Sciences, Beijing 100049, ing, crest length, defect density and crest direction etc., People’s Republic of China Vol.:(0123456789)1 3 347 Page 2 of 11 Environmental Earth Sciences (2020) 79:347 can be easily measured from the remote sensing images. Study area and methods As a convenient method, pattern analysis for active dune fields can obtain some valuable information from com- Study area plex spatial patterns (Ewing et al. 2006; Derickson et al. 2008; Fenton et al. 2014; Savage et al. 2014). Deserts are The Badain Jaran desert is located at east of the Heihe alluvial widely distributed in northern China (Wang 2011). As far fan, south of Guaizi lake, west of Zongnai mountain, north as we know, only a few pattern analyses for the Chinese of Heli, Beida, and Yabulai mountains in the northwest of dune fields have been conducted (Wu and Guo 2012; Li China, as shown in Fig. 1. The desert is 442 km long and 4 2 et al. 2016). The linear dunes in the northern Kumtagh 354 km wide, covering an area of 5.2 × 10 km (Zhu et al. desert might have developed since 13 ka BP (Wu and Guo 2010), and has a temperate continental climate with extreme 2012), if the empirical relations of Ewing et al. (2006) drought. It is cold and dry in winter, hot in summer, and the hold almost everywhere. Three possible evolution stages transition between summer and winter is very rapid. Precipita- of the linear dune field on the northern margin of Qarhan tion is scarce and mostly occurs in June, July and August. The Salt Lake were proposed in terms of the statistical char- overall topography of the desert is high in the southeast and acteristics and spatial variation of the pattern parameters low in the northwest. The mega-dunes, mainly concentrated (Li et al. 2016). In the evolution process of an active dune in the southeast of the desert, extend toward northeast–south- field, pattern parameters always change with the passage west, perpendicular to the prevailing northwest wind (Ning of time. But, the expressions of local pattern parameters and Wang 2018). Most of these dunes are between 200 and as functions of time remain unsolved in the aforemen- 300 m in height. The tallest terrestrial dune with the height of tioned works. 460 m is found in the desert (Yang et al. 2011). The types of Since dune fields often develop at the geologic time- mega-dunes include compound transverse dunes and complex scale, it is impossible to record their entire dynamic star dunes (Breed et al. 1979; Walker et al. 1987; Dong et al. process by the conventional field investigations and 2004, 2013). Many aeolian lakes exist between mega-dunes observations. Various chronological techniques have to (Wang et al. 2016). In this study, a few small solidifed or fos- be introduced. Optically stimulated luminescence (OSL) sil dunes occasionally distributed in this desert are not taken proposed by Huntley et al. (1985) is a powerful dating into account. tool for aeolian sediments in practice (Aitken 1998; Win- tle 2008; Zhang et al. 2015a). It is possible to reconstruct Data and methods the developmental stages of individual dunes by combina- tion of grand penetrating radar (GPR) and OSL (Bristow Following Ewing et al. (2006), crest length, dune orientation, et al. 2000, 2007). OSL is more suitable for the dunes mean spacing and defect density are selected as the dominat- with less or no migrations, because this method measures ing pattern parameters. Crest length refers to the boundary the elapsed years since the sediment was last consigned to between the windward and lee slope of dunes, which can darkness by burial. As for actively migrating dunes, OSL be used to measure the continuity of dune (Al-Masrahy and dating produces recent ages, whereas a pattern age rep- Mountney 2013). Dune orientation is defned as the angle resents the total development time of dune fields (Ewing between dune crest and the east direction. Dune spacing is et al. 2006). Moreover, for the extraterrestrial dune fields the horizontal distance between adjacent dune crests, which is (Greeley and Iversen 1985; Lorenz and Zimbelman 2014; closely related to formation time, initial conditions and defect Telfer et al. 2018), the direct dating techniques are cur- behavior of dunes. Given an area, the mean spacing is defned rently not available, pattern analysis is a great advantage. as (Werner and Kocurek 1999) For example, the Titan dunes have grown toward a steady A state for a long period of time (Savage et al. 2014), and Sp = , N L (1) the relation between dune spacing and “interaction” den- c sity on Earth, Mars, and Titan can be well described by where A is the area, and L and Nc are the mean length and a unified inverse quadratic function (Day and Kocurek number of crests in it. Defects are the breaking points or 2018). end points of dunes. The defect density, defned as the num- In the present study, the general relations between pat- ber of pairs of defects per unit of dune crest length, can be tern parameters and dune construction time are established expressed by frst. The local parameters of the Badain Jaran dune feld are then extracted from the remote sensing images and Nd = , (2) DEM, and their statistical characteristics and spatial NcL changes are quantifed. Finally, the pattern ages of the N whole dune feld are computed. where d is the number of defect pairs in the area of A. 1 3 Environmental Earth Sciences (2020) 79:347 Page 3 of 11 347 Fig. 1 Geographic setting of the Badain Jaran desert (BJD). The feld experiment performed by Ping et al. (2014) is sited in the Tengger desert. The sampling grids in the Badain Jaran desert are denoted by small rectangles The defnitions of (1) and (2) are convenient for dune squares in Fig.