Samples | S1 | S2 | S3 | TOC | Tmax |
|---|
Starting | 4.2 | 8.3 | 0.27 | 3.35 | 446 |
100% CH4 | 3.67 | 12.45 | 0.28 | 3.69 | 443 |
2% CH4 | 3.56 | 7.97 | 0.25 | 3.35 | 443 |
- Shale was prepared for analysis by grinding in argon to 60 mesh. Three aliquots were treated as follows: Aliquot 1: analyzed directly by Rock-Eval. Aliquot 2: Rock-Eval analysis after 9 exposures to methane (450 psi, 100°C, 10 min.). Aliquot 3: Rock-Eval analysis after 9 exposures to methane (450 psi, 100°C, 10 min.) followed by 5 exposures to 2% methane in helium (450 psi, 100°C, 10 min.). Samples in sealed brass containers were pressurized to 450 psi at 100°C for 10 minutes in each exposure, and slowly vented (1 minute) to atmospheric pressure. Samples showed no evidence of adsorbed methane after sequential exposures to methane; standard gc analysis: 1 g shale in 5 ml. Ar, 100°C, 1 hr. S1 = mg g-1 volatile hydrocarbons, < 300°C; S2 = mg g-1 solid hydrocarbon cracking, 350 – 550°C; S3 = mg CO2 g-1; TOC =% organic carbon. Values of starting shale are averages of triplicate analyses with sd: S1 ± 0.3; S2 ± 0.3; TOC ± 1.4; TMAX ± 3. Values for products are single analyses, although one (100% CH4) was verified in a second analysis. Rock-Eval analyses by GeoMark Research, Humble, Texas.
