“…These rocks have been named the Umphang Group by Meesook and Saengsrichan (2011). The Late Toarcian to basal Aalenian age (Early to Middle Jurassic) has been assigned to these rocks on the basis of paleontological evidences (ammonites, bivalves, large benthic foraminifera and algae) and stratigraphic correlation (Meesook and Grant-Mackie, 1996;Kozai et al, 2006Kozai et al, , 2011.…”