Abstract: A method of determining an API gravity of a crude oil is provided. The method includes obtaining a reservoir sample containing the crude oil and heating the sample to a first temperature using an oxidative testing apparatus. The sample is then heated to a second temperature, which is greater than the first temperature, over a period using a fixed heating rate. The rate of carbon dioxide emission from the sample is detected during the period of heating to the second temperature. The peak rate of carbon dioxide emission from the sample is then determined and the peak carbon dioxide emission temperature associated with the peak rate of carbon dioxide emission is also determined. The API gravity of the crude oil in the reservoir sample is determined using an empirical correlation between API gravity and the peak carbon dioxide emission temperature associated with the fixed heating rate.

Abstract: A method of determining an API gravity of a crude oil is provided. The method includes obtaining a reservoir sample containing the crude oil and heating the sample to a first temperature using an oxidative testing apparatus. The sample is then heated to a second temperature, which is greater than the first temperature, over a period using a fixed heating rate. The rate of carbon dioxide emission from the sample is detected during the period of heating to the second temperature. The peak rate of carbon dioxide emission from the sample is then determined and the peak carbon dioxide emission temperature associated with the peak rate of carbon dioxide emission is also determined. The API gravity of the crude oil in the reservoir sample is determined using an empirical correlation between API gravity and the peak carbon dioxide emission temperature associated with the fixed heating rate.

Abstract: An open system pyrolysis of a first hydrocarbon source rock sample obtained from a natural system is performed within a pyrolysis chamber by maintaining the pyrolysis chamber at a substantially constant temperature. Hydrocarbons are recovered from the pyrolysis chamber released by the first hydrocarbon source rock sample. A thermo-vaporization is performed within the pyrolysis chamber on the pyrolyzed sample at a substantially constant temperature. A first hydrocarbon expulsion efficiency of hydrocarbon source rock is determined. A second hydrocarbon rock sample is ground to a grain size less than or equal to or less than 250 micrometers. A second pyrolysis is performed on the ground hydrocarbon source rock sample by maintaining the chamber at a substantially constant temperature. A second hydrocarbon expulsion efficiency of the hydrocarbon source rock in the natural system is determined. The first hydrocarbon expulsion efficiency is verified using the second hydrocarbon expulsion efficiency.

Abstract: An open system pyrolysis of a first hydrocarbon source rock sample obtained from a natural system is performed within a pyrolysis chamber by maintaining the pyrolysis chamber at a substantially constant temperature. Hydrocarbons are recovered from the pyrolysis chamber released by the first hydrocarbon source rock sample. A thermo-vaporization is performed within the pyrolysis chamber on the pyrolyzed sample at a substantially constant temperature. A first hydrocarbon expulsion efficiency of hydrocarbon source rock is determined. A second hydrocarbon rock sample is ground to a grain size less than or equal to or less than 250 micrometers. A second pyrolysis is performed on the ground hydrocarbon source rock sample by maintaining the chamber at a substantially constant temperature. A second hydrocarbon expulsion efficiency of the hydrocarbon source rock in the natural system is determined. The first hydrocarbon expulsion efficiency is verified using the second hydrocarbon expulsion efficiency.

Abstract: A rock sample includes multiple rock samples that are each obtained from the borehole. The rock samples have been exposed to contamination during a drilling operation to drill the borehole. The rock sample is split into a first sample portion and a second sample portion. The first sample portion is decontaminated with a solvent. The second sample portion is decontaminated by thermovaporization for an initial duration of time at an initial thermovaporization temperature below that of a cracking temperature of an organic matter carried within the rock sample. A difference between a first pyrolysis Tmax value of the first sample portion decontaminated by the solvent and a second pyrolysis Tmax value of the second sample portion decontaminated by the thermovaporization is determined to satisfy a decontamination level threshold. The remainder of rock samples are decontaminated by the thermovaporization in response to determining that the difference satisfies the decontamination level threshold.

Abstract: An open system pyrolysis of a first hydrocarbon source rock sample obtained from a natural system is performed within a pyrolysis chamber by maintaining the pyrolysis chamber at a substantially constant temperature. Hydrocarbons are recovered from the pyrolysis chamber released by the first hydrocarbon source rock sample. A thermo-vaporization is performed within the pyrolysis chamber on the pyrolyzed sample at a substantially constant temperature. A first hydrocarbon expulsion efficiency of hydrocarbon source rock is determined. A second hydrocarbon rock sample is ground to a grain size less than or equal to or less than 250 micrometers. A second pyrolysis is performed on the ground hydrocarbon source rock sample by maintaining the chamber at a substantially constant temperature. A second hydrocarbon expulsion efficiency of the hydrocarbon source rock in the natural system is determined. The first hydrocarbon expulsion efficiency is verified using the second hydrocarbon expulsion efficiency.

Abstract: An open system pyrolysis of a first hydrocarbon source rock sample obtained from a natural system is performed within a pyrolysis chamber by maintaining the pyrolysis chamber at a substantially constant temperature. Hydrocarbons are recovered from the pyrolysis chamber released by the first hydrocarbon source rock sample. A thermo-vaporization is performed within the pyrolysis chamber on the pyrolyzed sample at a substantially constant temperature. A first hydrocarbon expulsion efficiency of hydrocarbon source rock is determined. A second hydrocarbon rock sample is ground to a grain size less than or equal to or less than 250 micrometers. A second pyrolysis is performed on the ground hydrocarbon source rock sample by maintaining the chamber at a substantially constant temperature. A second hydrocarbon expulsion efficiency of the hydrocarbon source rock in the natural system is determined. The first hydrocarbon expulsion efficiency is verified using the second hydrocarbon expulsion efficiency.

Abstract: A global objective function is initialized to an initial value. A particular model simulation process is executed using prepared input data. A mismatch value is computed by using a local function to compare an output of the particular model simulation process to corresponding input data for the particular model simulation process. Model objects associated with the particular model simulation process are sent to another model simulation process. An optimization process is executed to predict new values for input data to reduce the computed mismatch value.

Abstract: An open system pyrolysis of a first hydrocarbon source rock sample obtained from a natural system is performed within a pyrolysis chamber by maintaining the pyrolysis chamber at a substantially constant temperature. Hydrocarbons are recovered from the pyrolysis chamber released by the first hydrocarbon source rock sample. A thermo-vaporization is performed within the pyrolysis chamber on the pyrolyzed sample at a substantially constant temperature. A first hydrocarbon expulsion efficiency of hydrocarbon source rock is determined. A second hydrocarbon rock sample is ground to a grain size less than or equal to or less than 250 micrometers. A second pyrolysis is performed on the ground hydrocarbon source rock sample by maintaining the chamber at a substantially constant temperature. A second hydrocarbon expulsion efficiency of the hydrocarbon source rock in the natural system is determined. The first hydrocarbon expulsion efficiency is verified using the second hydrocarbon expulsion efficiency.

Abstract: A rock sample includes multiple rock samples that are each obtained from the borehole. The rock samples have been exposed to contamination during a drilling operation to drill the borehole. The rock sample is split into a first sample portion and a second sample portion. The first sample portion is decontaminated with a solvent. The second sample portion is decontaminated by thermovaporization for an initial duration of time at an initial thermovaporization temperature below that of a cracking temperature of an organic matter carried within the rock sample. A difference between a first pyrolysis Tmax value of the first sample portion decontaminated by the solvent and a second pyrolysis Tmax value of the second sample portion decontaminated by the thermovaporization is determined to satisfy a decontamination level threshold. The remainder of rock samples are decontaminated by the thermovaporization in response to determining that the difference satisfies the decontamination level threshold.

Abstract: A rock sample includes multiple rock samples that are each obtained from the borehole. The rock samples have been exposed to contamination during a drilling operation to drill the borehole. The rock sample is split into a first sample portion and a second sample portion. The first sample portion is decontaminated with a solvent. The second sample portion is decontaminated by thermovaporization for an initial duration of time at an initial thermovaporization temperature below that of a cracking temperature of an organic matter carried within the rock sample. A difference between a first pyrolysis Tmax value of the first sample portion decontaminated by the solvent and a second pyrolysis Tmax value of the second sample portion decontaminated by the thermovaporization is determined to satisfy a decontamination level threshold. The remainder of rock samples are decontaminated by the thermovaporization in response to determining that the difference satisfies the decontamination level threshold.

Abstract: A rock sample includes multiple rock samples that are each obtained from the borehole. The rock samples have been exposed to contamination during a drilling operation to drill the borehole. The rock sample is split into a first sample portion and a second sample portion. The first sample portion is decontaminated with a solvent. The second sample portion is decontaminated by thermovaporization for an initial duration of time at an initial thermovaporization temperature below that of a cracking temperature of an organic matter carried within the rock sample. A difference between a first pyrolysis Tmax value of the first sample portion decontaminated by the solvent and a second pyrolysis Tmax value of the second sample portion decontaminated by the thermovaporization is determined to satisfy a decontamination level threshold. The remainder of rock samples are decontaminated by the thermovaporization in response to determining that the difference satisfies the decontamination level threshold.

Abstract: An open system pyrolysis of a first hydrocarbon source rock sample obtained from a natural system is performed within a pyrolysis chamber by maintaining the pyrolysis chamber at a substantially constant temperature. Hydrocarbons are recovered from the pyrolysis chamber released by the first hydrocarbon source rock sample. A thermo-vaporization is performed within the pyrolysis chamber on the pyrolyzed sample at a substantially constant temperature. A first hydrocarbon expulsion efficiency of hydrocarbon source rock is determined. A second hydrocarbon rock sample is ground to a grain size less than or equal to or less than 250 micrometers. A second pyrolysis is performed on the ground hydrocarbon source rock sample by maintaining the chamber at a substantially constant temperature. A second hydrocarbon expulsion efficiency of the hydrocarbon source rock in the natural system is determined. The first hydrocarbon expulsion efficiency is verified using the second hydrocarbon expulsion efficiency.

Abstract: A global objective function is initialized to an initial value. A particular model simulation process is executed using prepared input data. A mismatch value is computed by using a local function to compare an output of the particular model simulation process to corresponding input data for the particular model simulation process. Model objects associated with the particular model simulation process are sent to another model simulation process. An optimization process is executed to predict new values for input data to reduce the computed mismatch value.

Abstract: Some examples of pyrolysis to determine hydrocarbon expulsion efficiency of hydrocarbon source rock can be implemented by performing an open system pyrolysis of a hydrocarbon source rock sample obtained from a natural system. Sample includes hydrocarbon source rocks having an equivalent spherical diameter of substantially at least one centimeter. After the open system pyrolysis, the sample can be crushed and thermally vaporized. A hydrocarbon expulsion efficiency of hydrocarbon source rock in the natural system can be determined based on hydrocarbons recovered in response to the open system pyrolysis and in response to the crushing and thermal vaporization.