Page 67 - Introduction to Paleobiology and The Fossil Record

Metamorphic zones Diagenetic zone Anchizone Epizone Mesozone
Various measures of thermal maturation. Color changes recorded in conodonts (CAI), together with corresponding values for vitrinite
reflectance and the translucency index of palynmorphs, are related to the oil and gas window and metamorphic grades and zones. (Based on

Metamorphic grade ↑ oil and gas window ↓ dry gas

Thermal alteration index approx. 1.5 2.0 2.5 2.7 3.2 3.5 4.0 5.0 lower greenschist chlorite/muscovite greenschist meta-argillite upper greenschist biotite-garnet garnet

Palynomorph translucency index 1–5 5–5ur 5–6 5ur–6 6 6ur–7

Vitrinite ectance refl 0.8 0.7–0.85 0.85–1.3 1.4–1.95 1.95–3.6 3.6

Mean temperature (˚C) 65 70 100 135 160 205 245 285 330 365 400 460 550

Paleotemperature (˚C) 50–80 50–90 60–140 85–180 110–200 150–260 190–300 230–340 300–400 310–420 350–435 425–500 480–610 >530 >600

Jones, G.L. 1992. Terra Nova 4.) Color pale yellow very pale brown brown to dark brown very dark gray-brown light black dense black dark gray-black gray gray-white opaque white semi-translucent crystal clear

Table 2.2 CAI 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8