GENERAL GEOLOGY

Detailed explanation-1: -Tmax = the temperature at which the maximum release of hydrocarbons from cracking of kerogen occurs during pyrolysis (top of S2 peak). Tmax is an indication of the stage of maturation of the organic matter.

Detailed explanation-2: -Tmax is the temperature at which the maximum rate of hydrocarbon generation occurs in a kerogen sample during pyrolysis analysis. The S2 peak represents the rate of hydrocarbon generation (the area under the curve represents the amount).

Detailed explanation-3: -Optimal formation temperatures for maturation and catagenesis range from 90° to 125 °C, reached at burial depths between 2 and 4 km. Greater depth and higher temperature destroy the hydrocarbons. After oil and gas form, propelled by their buoyancy, they migrate from source rocks to porous and permeable reservoir rocks.

Detailed explanation-4: -As temperatures and pressures increase (deeper burial) the process of catagenesis begins, which is the thermal degradation of kerogen to form hydrocarbon chains.

Detailed explanation-5: -This requires that the temperature must be 80–150◦C over long geological time (typically 1–100 million years). The conversion of kerogen to oil and gas is thus a process which requires both higher temperatures than one nds at the surface of the earth and a long period of geological time.