“…In contrast to clay-rich mudstones (shales), whose diagenetic evolution has received much attention (for example, Nadeau et al, 2005;Laughrey et al, 2011;Milliken and Olson, 2017;Roberts and Elmore, 2018), coarser grained silt-rich mudstones (siltstones) are considerably understudied, with only one publication investigating the diagenesis of a pure siltstone (Orberger and Pagel, 2000) that documents physical compaction, diagenetic alteration of detrital quartz, Kfeldspar and mica and precipitation of calcite and dolomite cements. Although it has been established that rock fabric (grain size and sorting) of mudstones significantly affects both diagenetic processes and reservoir quality (Peng et al, 2020;Wilson et al, 2020), studies of the composition and diagenesis of mixed siltstone-mudstone or sandstone-siltstone sequences (e.g., Varga et al, 2005;Taylor and Macquaker, 2014;Lai et al, 2016;Cao et al, 2017) rarely focused on silty intervals, or grouped siltstones and fine sandstones together (McBride, 1989).…”