What is Tmax in Rock Eval pyrolysis?

Tmax is the temperature at which the maximum rate of hydrocarbon generation occurs in a kerogen sample during pyrolysis analysis. The temperature at the time the S2 peak is recorded during pyrolysis is Tmax, given in °C. Figure 1 shows output from a pyrolysis analysis and when Tmax is recorded.

What is S2 in Rock Eval?

Rock Eval pyrolysis S2 = the amount of hydrocarbons generated through thermal cracking of nonvolatile organic matter. Tmax = the temperature at which the maximum release of hydrocarbons from cracking of kerogen occurs during pyrolysis (top of S2 peak).

How does Rock Eval work?

The Rock Eval (RE) pyrolysis method consists of a programmed temperature heating (in a pyrolysis oven) in an inert atmosphere (helium) of a small sample (~100 mg) to quantitatively and selectively determine (1) the free hydrocarbons contained in the sample and (2) the hydrocarbon- and oxygen-containing compounds (CO2) …

What is pyrolysis in geology?

Pyrolysis is the decomposition of organic matter by heating in the absence of oxygen. Organic geochemists use pyrolysis to measure richness and maturity of potential source rocks. The amount of hydrocarbons and carbon dioxide released is measured. The most widely used pyrolysis technique is Rock-Eval.

What role does kerogen play in generation?

Formation. The formation of kerogen represents a major step in the formation of oil and natural gas, as kerogen serves as the source of these fossil fuels. For kerogen to form, dead phytoplankon, zooplankton, algae, and bacteria must sink to the bottom of an ancient still water environment.

What is the hydrogen index?

The number of hydrogen atoms per unit volume divided by the number of hydrogen atoms per unit volume of pure water at surface conditions. The hydrogen index (HI) is thus the density of hydrogen relative to that of water. It is a key factor in the response of a neutron porosity log.

What is maturation petroleum geology?

Maturation is the conversion of organic matter to hydrocarbons. The first stage is the formation of kerogen. As the pressure and temperature is the source rock is further increase, kerogen converts to petroleum. If the temperature is raised above 130C for even a short period of time, crude oil will convert to gas.

What is Rock Eval instrument?

Description. The Rock-Eval 7 is the fully automated Vinci instrument that performs geochemical analysis of kerogen-containing rock samples.

What is source rock in oil and gas?

Petroleum source rock is defined as the fine-grained sediment with sufficient amount of organic matter, which can generate and release enough hydrocarbons to form a commercial accumulation of oil or gas [1]. Source rocks are commonly shales and lime mudstones, which contain significant amount of organic matter [2].

How do you identify kerogen?

Determining kerogen quality The type of kerogen present in a rock determines its quality. Type I kerogen is the highest quality; type III is the lowest. Type I has the highest hydrogen content; type III, the lowest.

What is difference between kerogen and bitumen?

Kerogen—the organic matter that is solid and insoluble in organic solvents—is a key component of organic-rich mudstones. Kerogen is consumed during thermal maturation, whereas bitumen is an intermediary formed at low maturity from kerogen and consumed at higher maturities in formation of oil and gas.

What does the index of hydrogen deficiency tell you?

By calculating the index of hydrogen deficiency (IHD), we can tell from the molecular formula whether and how many multiple bonds and rings are involved. This will help cut down the possibilities one has to consider in trying to come up with all the isomers of a given formula.