	US 12,111,305 B2
	Method for determining subsurface hydrocarbon fluid properties of reservoired hydrocarbons
Leslie Owuraku Baksmaty, Houston, TX (US); Ram Ratan Ratnakar, Houston, TX (US); and Birol Dindoruk, Houston, TX (US)
Assigned to SHELL USA, INC., Houston, TX (US)
Appl. No. 17/611,349
Filed by SHELL OIL COMPANY, Houston, TX (US)
PCT Filed Jun. 12, 2020, PCT No. PCT/US2020/037412 § 371(c)(1), (2) Date Nov. 15, 2021, PCT Pub. No. WO2020/252246, PCT Pub. Date Dec. 17, 2020.
Claims priority of provisional application 62/860,847, filed on Jun. 13, 2019.
Claims priority of application No. 19185152 (EP), filed on Jul. 9, 2019.
Prior Publication US 2022/0205970 A1, Jun. 30, 2022
Int. Cl. G01N 33/24 (2006.01); E21B 49/08 (2006.01); G01V 1/38 (2006.01)

CPC G01N 33/241 (2013.01) [E21B 49/08 (2013.01); G01V 1/3808 (2013.01)]

9 Claims

1. A method for determining the fluid properties of subsurface reservoired hydrocarbons having a hydrocarbon seep, the method comprising the steps of:

a) locating a hydrocarbon seep at a seabed location where hydrocarbons are actively flowing out of the seabed;

b) collecting a sample of hydrocarbons from the hydrocarbon seep;

c) determining the fluid properties of subsurface reservoired hydrocarbons from the sample of hydrocarbons, the fluid properties selected from the group consisting of physical, transport and thermodynamic properties; and

d) determining whether the seep is at a steady state, indicative of reservoired hydrocarbons, by

(i) determining at least two temporally spaced compositions of the hydrocarbon seep, the at least temporally spaced compositions selected from the group consisting of isotopic compositions, molecular compositions, and combinations thereof,

(ii) determining a temporal variance between the at least two temporally spaced compositions; and

(iii) when the temporal variance falls with a predetermined temporal tolerance classifying the hydrocarbon seep as being indicative of the presence of reservoired hydrocarbons.