Figure F19. Microfacies of bioturbated nannofossil limestone from transition zone between Subunits IIIB and IIIA (Sample 192-1186A-26R-3, 24-27 cm; late Coniacian) (field of view = 2.8 mm; plane-polarized light; photomicrograph ID# 1186AS_14). The thin section shows a complex interfingering of brown, nearly unfossiliferous, clayey layers with abundant volcaniclastic grains and gray mudstone intervals with frequent, tiny planktonic foraminifers and much rarer volcaniclastic grains. Opaque minerals and clay are common.

Figure F19. Microfacies of bioturbated nannofossil limestone from transition zone between Subunits IIIB and IIIA (Sample 192-1186A-26R-3, 24-27 cm; late Coniacian) (field of view = 2.8 mm; plane-polarized light; photomicrograph ID# 1186AS_14). The thin section shows a complex interfingering of brown, nearly unfossiliferous, clayey layers with abundant volcaniclastic grains and gray mudstone intervals with frequent, tiny planktonic foraminifers and much rarer volcaniclastic grains. Opaque minerals and clay are common.