Method of assessing at least one petroleum characteristic of a rock sample

Patent metadata

Field	Value
Publication number	US-2015346179-A1
Application number	US-201514725483-A
Country	US
Kind code	A1
Filing date	May 29, 2015
Priority date	Jun 3, 2014
Publication date	Dec 3, 2015
Grant date	—

Abstract

The invention is a Method of assessing at least one petroleum characteristic of a rock sample. Starting from a temperature ranging between 50° C. and 120° C., the temperature of a rock sample is raised to a temperature ranging between 180° C. and 220° C. which is maintained for a predetermined time duration. The temperature of the sample is increased to a temperature ranging between 330° C. and 370° C. which is maintained for a predetermined time duration. The temperature of the sample is then raised to a temperature ranging between 630° C. and 670° C. Three quantities representative of the amount of hydrocarbon compounds released during the temperature change stages are measured and at least one petroleum characteristic of the sample is deduced from these quantities.

First claim

17 . A method of assessing at least one petroleum characteristic of a rock sample from a geological formation, wherein a sample is heated in an inert atmosphere according to a temperature sequence, comprising:
a) raising a temperature of the sample from a first temperature ranging between 50° C. and 120° C., according to a first temperature gradient ranging between 1° C./min and 50° C./min, to a second temperature ranging between 180° C. and 220° C., and maintaining the sample at the second temperature for a first predetermined time duration; b) raising the temperature of the sample from the second temperature according to a second temperature gradient ranging between 1° C./min and 50° C./min to a third temperature ranging between 330° C. and 370° C., and maintaining the sample at the third temperature for a second predetermined time duration; c) raising the temperature of the sample from the third temperature according to a third temperature gradient ranging between 1° C./min and 50° C./min to a fourth temperature ranging between 630° C. and 670° C.; d) determining three quantities representative of the measured amount of hydrocarbon compounds released in steps a), b) and c) respectively; e) determining, from at least one of the three quantities, at least one petroleum characteristic of the sample.

18 . A method as claimed in claim 17 , wherein the rock sample comprises a hydrocarbon source rock.

19 . A method as claimed in claim 17 , wherein the first temperature ranges between 80° C. and 120° C.

20 . A method as claimed in claim 17 , wherein the first temperature ranges between 90° C. and 110° C.

21 . A method as claimed in claim 19 , wherein the first temperature ranges between 90° C. and 110° C.

22 . A method as claimed in claim 17 wherein, at a start of step a), the sample is maintained at the first temperature.

23 . A method as claimed in claim 17 , wherein the second temperature ranges between 190° C. and 210° C.

24 . A method as claimed in claim 19 , wherein the second temperature ranges between 190° C. and 210° C.

25 . A method as claimed in claim 17 , wherein the third temperature ranges between 340° C. and 360° C.

26 . A method as claimed in claim 19 , wherein the third temperature ranges between 340° C. and 360° C.

27 . A method as claimed in claim 17 , wherein the fourth temperature ranges between 640° C. and 660° C.

28 . A method as claimed in claim 19 , wherein the fourth temperature ranges between 640° C. and 660° C.

29 . A method as claimed in claim 25 , wherein the fourth temperature ranges between 640° C. and 660° C.

30 . A method as claimed in claim 18 , wherein the first and second time durations range between 2 and 4 minutes.

31 . A method as claimed in claim 17 , wherein the first, second and third temperature gradients range between 20° C./min and 30° C./min.

32 . A method as claimed in claim 17 , wherein the petroleum characteristic of the sample calculated in e) is selected from a free hydrocarbon content index denoted by a quality index of hydrocarbons, a production index, an API degree, a GOR parameter and a GCR parameter.

33 . A method as claimed in claim 32 , wherein the free hydrocarbon content index is calculated according to a formula as follows:
HC cont =S h0 +S h1 wherein S h0 , S h1 and HC cont are expressed in milligrams of hydrocarbon compound per gram of rock.

34 . A method as claimed in claim 32 , wherein a quality index HQI of the hydrocarbons is calculated according to a formula as follows:

HQI
=

S

h



0

S

h



0

+

S

h



1

×
100

wherein S h0 and S h1 are expressed in milligrams of hydrocarbon compound per gram of rock and HQI is expressed as percentage by mass.

35 . A method as claimed in claim 32 , wherein a production index is calculated according to the formula as follows:

PI
Shale

=

(

S

h



0

+

S

h



1

)

(

S

h



0

+

S

h



1

+

S

h



2

)

×
100

wherein S h0 , S h1 and S h2 an expressed in milligrams of hydrocarbon compound per gram of rock, and PI Shale is expressed as a percentage by mass.

36 . A method as claimed in claim 35 , wherein calculation of the production

Assignees

• IFP Energies Nouvelles

Inventors

• Pillot Daniel
• Letort Geremie
• Romero-Sarmiento Maria-Fernanda
• Lamoureux-Var Violaine
• Beaumont Valerie
• Garcia Bruno

Classifications

• G01N2203/0694

  Temperature · CPC title

• G01N33/0047

  Organic compounds · CPC title

• G01N33/004

  CO or CO2 · CPC title

• G01V9/005

  by thermal methods, e.g. after generation of heat by chemical reactions · CPC title

• G01N33/241 Primary

  for hydrocarbon content · CPC title