Figure 12. Elements of our Petroleum System Process Model: 1) Deposition of hydraulically isolated and low relief sands bodies onto organic rich, self-sourcing shale facies; 2) Burial of sand and increase in temperature and pressure; 3) Hydrocarbon generation via organic diagensis; 4) Local hydrocarbon migration into isolated sand bodies; 5) In-situ hydrocarbon catagenesis and metagenesis causing a build-up of pressure from the fluid volume exchange and removal of all but the irreducible pore waters; 6) Cyclic process of: a) pressurizing the isolated sand bodies, b) vaporizing the irreducible pore fluids, c) leaking due to seal breach by the abnormal pressure, d) resealing of the shale facies once the pressure has decreased below the seal pressure, e) recharging by interbedded organic shales that continue to generate hydrocarbons at a greater rate than they can be diffused.