1. Ch.9 Diagenesis, Catagenesis, & Metagenesis

3.
The changes in H/C and O/C atomic ratios for the pyrolysis of the Cameo coal from the Twin Arrow 4-14 C&K well as shown on a Van Krevelen diagram indicate that the simulated maturation of the coal follows the natural evolution trend for type III kerogen. The two faint dotted lines running from about 1.7 and 0.7 on the y axis to 0.18 and 0.14 on the x axis represent the stage boundaries of organic matter transformation from diagenesis to catagenesis and from catagenesis to metagenesis, respectively

4. Types of Kerogen Type I Type II Type III Type IV H/C ~1.6 ~1.3~
~0.5
Oxygen % ~5
~10
~25-30
Sources
Algal, bacterial
Mixed (cuticles, spores, pollen, plant debris)
Woody tissues
Fusitinized OM
High aliphatic, low aromatic
More aromatic
Not much aliphatic
Very highly aromatic
Oil Generation Potential
Very high
High
Low (gas prone)
Zero

8. Diagenesis Catagenesis Metagenesis H보다 O가 주로 감소 (C=O 제거를 통해) Ro ≤ 0.5%
Magnetic susceptibility χ ≤5*10-9 emu CGS/ g OC
Catagenesis
H, H/C 급격히 감소탄화수소(석유) 발생
잔류 C=O 제거
Main oil generation zone/Beginning of cracking zone (wet gas)
Aliphatic 감소, aromatic (napthene ring) 증가  aromatization
Ro ≒ 0.5-2%
χ ≒50-60*10-9 emu CGS/ g OC
Metagenesis
H 감소 둔화, H/C ≤ 0.5
Aliphatic, C=O 사라짐
Ro ≥ 2%
χ 최대치에 도달한 후 다시 감소
Dry gas zone