Fig. 2
a Map of China (modified according to the standard map GS(2016)2923 available on the official website of National Geomatics Center of China) showing the location of Ordos Basin; b Map of Ordos Basin and location of studied outcrops: ①Shijiachuan and ②Yangmahe in Zichang County, Yan’an City and ③Yaoqu in Yao County, Tongchuan City; c) Comprehensive stratigraphy column of Ordos Basin (modified after Pan et al. 2017). Fm. = Formation