Figure 12.

(A–C) SEM images in BSE mode of sample E40 (KCF) showing typical OM particles of KCF rocks (A) before thermal maturation and after maturation at (B) 390 and (C) 470 °C for 72 h. Insets in (A–C) are SE images showing the progressive evolution of the OM texture during maturation. (D–F) SEM images in SE mode showing the dominant texture of OM in sample E40 after maturation at (D) 325, (E) 390 and (F) 470 °C for 72 h. The OM texture evolved from a homogeneous smooth nonporous texture to a very porous granular texture with increasing maturity. The orange arrow in (C) shows a large macropore probably resulting from the important conversion of the OM particle during gas generation, leaving behind a large pore lined with residual OM.