“…Previous studies have attempted to solve the genetic mechanism of these two types of kaolinite‐rich claystones. Thus, a series of discriminatory indicators have been proposed, mainly including mineral components, kaolinite morphology; and crystallinity (Dai et al, 2014; Ding, Liu, & Wang, 2009; Liu, Spears, Zhang, & Xu, 2001; Zadvernyuk, Kadoshnikov, Shekhunova, & Remez, 2021). However, these studies have focused more on the petrological and mineralogical differences between the two types of claystones, ignoring the differences in their geochemical characteristics.…”