METHOD FOR DETERMINING THE PRESENCE AND LOCATION OF AN ACCUMULATION OF SUBSUPERFACE HYDROCARBONS AND

专利摘要:
a method for determining the presence and location of a subsurface hydrocarbon accumulation and the origin of the associated hydrocarbons a method for determining the presence and location of a subsurface hydrocarbon accumulation in a naturally occurring substance sample. a concentration of isotopologists of a hydrocarbon species is determined. an expected temperature dependence of the isotopologists present in the sample is modeled using high-level ab initio calculations. a grouped isotope signature of the isotopologists present in the sample is measured. the grouped isotopic signature is compared to the expected concentration of isotopologists. using the comparison, it is determined whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample have escaped from a subsurface accumulation. the current equilibrium storage temperature of the hydrocarbon species from the subsurface accumulation, before escaping to the surface, is determined. a location of subsurface accumulation is determined. this information can be integrated with the pre-drilling basin historical models to calibrate a basin model.
公开号:BR112014007825B1
申请号:R112014007825-4
申请日:2012-08-27
公开日:2021-03-23
发明作者:Robert J. Pottorf；Michael Lawson；Steven R. May；Sebastien Dreyfus；Sumathy Raman
申请人:Exxonmobil Upstream Research Company；
IPC主号:

专利说明:

[0001] [0001] This application claims the benefit of Provisional Patent Application US 61 / 558,822, filed on November 11, 2011, entitled METHOD FOR DETERMINING THE PRESENCE AND LOCATION OF A SUBSURFACE HYDROCARBON ACCUMULATION AND THE ORIGIN OF THE ASSOCIATED HYDROCARBONS incorporated herein by reference. FIELD OF THE INVENTION
[0002] [0002] The embodiments of the present description generally refer to the field of geochemistry. More particularly, the present description relates to systems and methods for determining the origin and storage temperature (and, consequently, the depth) of subsurface hydrocarbon accumulations. BACKGROUND OF THE INVENTION
[0003] [0003] This section is intended to introduce various aspects of the art, which can be associated with the exemplary embodiments of the present description. This discussion is believed to assist in providing a framework to facilitate a better understanding of the particular aspects of the present invention. Therefore, it should be understood that this section should be read in this light and not necessarily as admissions to the prior art.
[0004] [0004] The main components required for the presence of subsurface hydrocarbon accumulations in a sedimentary basin are (1) the generation and expulsion of liquid hydrocarbons from a source rock, (2) migration of liquid hydrocarbons to an accumulation in a reservoir, (3) a trap and a seal to prevent significant leakage of hydrocarbons from the reservoir.
[0005] [0005] Currently, seismic reflection is the dominant technology for the identification of hydrocarbon accumulations. This technique has proven successful in identifying structures that can house hydrocarbon accumulations and, in some cases, has been used to imagine hydrocarbon fluids within subsurface accumulations. However, in some cases, this technology does not have the required fidelity to provide accurate estimates of the location of subsurface hydrocarbon accumulations, due to poor subsurface imaging. Additionally, it is not easy to differentiate the presence and types of hydrocarbons from other fluids in the subsurface by remote measurements.
[0006] [0006] Current non-seismic hydrocarbon detection technologies do not significantly improve our ability to identify the location of a hydrocarbon accumulation. For example, the infiltration of hydrocarbons on the seabed or on land provides some indication of an active or functioning hydrocarbon system, where hydrocarbons were generated and expelled during the thermal maturation of a source rock in depth, and migrated via migration paths. more or less complex for the surface. However, it is difficult for current non-seismic technologies to determine whether such hydrocarbon infiltrations have migrated directly from a source rock or an accumulation of hydrocarbons, and it is not possible to locate subsurface accumulations associated with the infiltrations.
[0007] [0007] As such, there is a need for additional techniques that can more effectively detect the presence and location of hydrocarbon accumulations on the subsurface. In particular, a relatively inexpensive and fast method for determining the presence and location of an accumulation of subsurface hydrocarbons and the origin of the associated hydrocarbons (ie, facies and thermal maturity of the source of the source rock that generated these hydrocarbons) would provide a valuable tool that could be used in hydrocarbon exploration at all levels of commercial stage maturity, from frontier exploration to the extension of proven plays (conceptual models of hydrocarbon accumulation) or high-grade explorations in proven plays. SUMMARY OF THE INVENTION
[0008] [0008] According to the described aspects and methodologies, a system and method is provided to estimate / determine the equilibrium temperature of hydrocarbon samples.
[0009] [0009] According to the described aspects and methodologies, a method of determining the presence and location of an accumulation of subsurface hydrocarbons, from a naturally occurring substance sample, is described. According to the method, an expected concentration of isotopologists of a hydrocarbon species is determined. An expected temperature dependence of isotopologists present in the sample is modeled using high-level ab initio calculations. An agglomerated isotopic signature of the isotopologists present in the sample is measured. The clustered isotopic signature is compared with the expected concentration of isotopologists. Using the comparison, it is determined whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample escaped a subsurface accumulation. The current equilibrium storage temperature of hydrocarbon species from subsurface accumulation before escaping to the surface is determined. A location for subsurface accumulation is determined.
[0010] [0010] Also according to the methodologies and techniques described, a method is provided to determine the presence and location of an accumulation of subsurface hydrocarbons. According to the method, a hydrocarbon sample is obtained from a spring. The hydrocarbon sample is analyzed to determine its geochemical signature. The analysis includes measuring a distribution of isotopologists for a hydrocarbon species present in the hydrocarbon sample. A stochastic distribution of isotopologists for the hydrocarbon species is determined. A deviation from the measured distribution of isotopologists from the stochastic distribution of isotopologists for the hydrocarbon species is determined. The origin of the hydrocarbon sample is determined. The storage temperature of the hydrocarbon species is determined when the source of the hydrocarbon sample is an accumulation of hydrocarbon. By the storage temperature, the location of the hydrocarbon accumulation is determined.
[0011] [0011] According to the methodologies and techniques described here, a method is provided to determine the presence of an accumulation of subsurface hydrocarbons by a sample of the naturally occurring substance. According to the method, an expected concentration of isotopologists of a hydrocarbon species is determined. An expected temperature dependence of the isotopologists present in the sample is modeled using high-level ab initio calculations. A grouped isotopic signature of the isotopologists present in the sample is measured. The grouped isotopic signature is compared with the expected concentration of isotopologists. It is determined, using the comparison, whether the hydrocarbons present in the sample escaped from a subsurface accumulation, thereby determining the presence of subsurface accumulation.
[0012] [0012] According to the methodologies and techniques described, a computer system is provided that is configured to determine the presence and location of an accumulation of subsurface hydrocarbons in a naturally occurring substance sample. The computer system includes a processor and a machine-readable tangible storage medium, which stores machine-readable instructions for execution by the processor. Machine-readable instructions include: code to determine an expected isotopologist concentration of a hydrocarbon species; code to model, using high-level ab initio calculations, an expected temperature dependence of the isotopologists present in the sample; code to measure an agglomerated isotopic signature of the isotopologists present in the sample; code to compare the agglomerated isotopic signature with the expected concentration of isotopologists; and code to determine, using said comparison, whether the hydrocarbons present in the sample originated directly from a source rock or whether the hydrocarbons present in the sample escaped from a subsurface accumulation.
[0013] [0013] According to still described methodologies and techniques, a method is provided to determine the presence and location of an accumulation of subsurface hydrocarbons and the origin of associated hydrocarbons, collected from a surface spring. According to the method, molecular modeling is integrated to determine the expected concentration of isotopologists of a hydrocarbon species of interest. A concentration of the isotopologists of the hydrocarbon species of interest is measured. Statistical regression analysis is conducted to converge on a temperature dependent equilibrium constant and a single signature for the absolute concentrations measured for multiple coexisting isotopologists. For hydrocarbons collected from the surface spring, at least one of storage temperature, a source facies and thermal maturity of source rock, associated with them, is determined.
[0014] [0014] These and other details and advantages of the present description will be readily apparent when considering the following description, together with the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015] Figure 1 is a side elevation view of a seabed;
[0016] [0016] Figure 2 is a flow diagram of a method according to the methodologies and techniques described;
[0017] [0017] Figure 3 is a graph of isotopologist concentration versus temperature;
[0018] [0018] Figure 4 is a block diagram of a computer system according to the methodologies and techniques described; and
[0019] [0019] Figure 5 is a flow diagram, representing machine-readable instructions, according to the methodologies and techniques described. DETAILED DESCRIPTION OF THE INVENTION
[0020] [0020] Various terms as used herein are defined below. Insofar as a term used in a claim is not defined below, it should be given the definition that people in the relevant art have given that term, in the context in which it is used.
[0021] [0021] As used herein, "an" entity refers to one or more of that entity. As such, the terms "one" (or "one"), "one or more" and "at least one" can be used interchangeably here, unless a limit is specifically quoted.
[0022] [0022] As used herein, the terms "comprising", "understands", "understand", "understood", "containing", "contains", "having", "has", "have", "including", " includes ”and“ include ”are transition terms that are amenable to extension, used for transition from a cited subject, before the term to one or more elements cited after the term, where the element or elements listed after the transition term are not necessarily the only elements that make up the subject.
[0023] [0023] As used here, "exemplary" means exclusively "serving as an example or illustration". Any embodiment described here as exemplary is not to be interpreted as preferred or advantageous over other embodiments.
[0024] [0024] As used here, "hydrocarbons" are generally defined as molecules formed primarily of carbon and hydrogen atoms such as oil and natral gas. Hydrocarbons can also include other elements or compounds, such as but not limited to halogens, metallic elements, nitrogen, oxygen, sulfur, hydrogen sulfide (H2S) and carbon dioxide (CO2). Hydrocarbons can be produced from hydrocarbon reservoirs through wells penetrating a formation containing hydrocarbons. Hydrocarbons derived from a hydrocarbon reservoir may include, but are not limited to, petroleum, kerogen, bitumen, pyrobetum, asphaltenes, tar, natural gas or combinations thereof. Hydrocarbons can be located inside or adjacent to mineral matrices inside the earth, called reservoirs. The matrices may include, but are not limited to, sedimentary rock, sands, silicillites, carbonates, diatomites and other porous media.
[0025] [0025] As used herein, “hydrocarbon production” refers to any activity associated with the extraction of hydrocarbons from a well or other opening. Hydrocarbon production normally refers to any activity conducted in or on the well, after the well is completed. Therefore, the production or extraction of hydrocarbons includes not only primary extraction of hydrocarbons, but also secondary and tertiary production techniques, such as injection of gas or liquid to increase the thrust pressure, mobilizing the hydrocarbon or treating the well, for example. , by chemical or hydraulic fracturing, to promote increased flow, well maintenance, well measurement and other well and well drilling treatments.
[0026] [0026] As used here, the term "isotope" refers to one of two or more atoms with the same atomic number, but with different numbers of neutrons. Hydrocarbon molecules can contain a variety of isotopes. Hydrocarbon molecules contain both carbon and hydrogen atoms. Carbon can be present in the molecule as one of two stable isotopes: 12C, which has 6 protons and 6 neutrons (shown here as C); and, at very low concentrations, 13C, which has 6 protons and 7 neutrons. Similarly, hydrogen can be present in a molecule as one of two stable isotopes: H, which contains 1 proton, but not a neutron; and, in much lower concentrations, Deuterium (D), which has 1 proton and 1 neutron.
[0027] [0027] As used here, the term "signatures" refers to the abundances, concentrations and / or abundance ratios of the various elements, isotopes and isotopologists of a given species.
[0028] [0028] As used here, the term "isotopologist" generically refers to molecules that have the same chemical composition, but have different isotopic signatures; for example, methane contains 1 carbon atom and four hydrogen atoms. Each atom in the methane structure can contain one of the two stable isotopes of that atom and, as such, there are 10 possible methane isotopologists.
[0029] [0029] As used here, the term "multiply substituted isotopologist" refers generically to an isotopologist that contains at least two rare isotopes in its structure; for example, a multiply substituted methane isotopologist must contain a 13C atom and a D atom, or at least 2 D atoms, in the absence of a 13C atom.
[0030] [0030] As used here, the term "clustered isotopologist" refers to an isotopologist that contains at least two rare isotopes, which share a chemical bond in their structure; for example, a clustered methane isotopologist must have a 13C atom, which shares a chemical bond with at least one D atom.
[0031] [0031] As used herein, the term "stochastic distribution" refers generically to a system in which the stable isotopes of a given population of molecules are randomly distributed among all possible isotopologists of a given species. This stochastic distribution is the reference framework from which deviations are measured and is used to provide a baseline for identifying anomalies that can be associated with secondary isotope exchange processes.
[0032] [0032] Although for the sake of simplicity of explanation the illustrated methodologies are shown and described as a series of blocks, it should be appreciated that the methodologies are not limited by the order of the blocks, since some blocks can occur in different orders and / or concurrently with other blocks from the one shown and described. In addition, less than all the illustrated blocks may be required to implement an example methodology. The blocks can be combined or separated into multiple components. In addition, additional and / or alternative methodologies may employ additional blocks not illustrated. Although the figures illustrate several actions occurring serially, it should be appreciated that several actions could occur concurrently, substantially in parallel, and / or at substantially different points of time.
[0033] [0033] In the following section, specific embodiments of the present invention are described in connection with described aspects and techniques. However, insofar as the following description is specific to an aspect, particular technique, or a particular use, it is intended to be for exemplary purposes only. Therefore, the invention is not limited to the aspects and techniques described below, however, it undoubtedly includes the alternatives, modifications and equivalents falling within the scope of the appended claims.
[0034] [0034] According to aspects of the methodologies and techniques described, the grouped isotope signature of numerous coexisting hydrocarbon isotopologists can be used to determine (i) the presence and depth of an accumulation of subsurface hydrocarbons and, (ii) through integration with more conventional isotopic and molecular geochemical techniques, the origin of the associated hydrocarbons. With more integration with conventional geophysical techniques, such as seismic reflection, the precise location (depth plus lateral location) of subsurface hydrocarbon accumulation can be identified.
[0035] [0035] Figure 1 is a diagram illustrating the numerous subsurface sources and hydrocarbon migration paths present in or escaping from springs in the ocean floor 100. Hydrocarbons 102, generated in the source rock (not shown) migrate upward through faults and fractures 104. If limited by subsurface geology, hydrocarbons can be trapped in hydrocarbon accumulations, such as a gas reservoir 106, an oil / gas reservoir 108, or a hydrate gas accumulation 110. Hydrocarbons infiltrating of the accumulation of gaseous hydrate may dissolve within methane in ocean 112, as shown in 114, or may remain as a gaseous hydrate in ocean bed 100, as shown in 116. Alternatively, oil or gas from oil / gas reservoir 108 can seep into the ocean, as shown in 118, and form an oil slick 120 on the surface of ocean 122. The gas leaking from the gas reservoir can form a bac teriana 124, which can generate biogenic hydrocarbon gases, which is another sign of infiltration. Yet another method of hydrocarbon infiltration is via a mud volcano 126, which can form an oil slick 128 on the surface of the ocean. The oil stains 120 and 128 or methane gas 130 emitted by them are signs of hydrocarbon infiltration, which are, in turn, signs of possible hydrocarbon accumulation. The measured signatures of each of these infiltrations can be questioned according to methodologies and techniques described here, to discriminate between the different origins of the hydrocarbons found in these infiltrations. In particular, this invention will discriminate between hydrocarbons that have migrated directly to surface infiltration without finding a structure / seal within which they can be stored (source 1) and hydrocarbons that have escaped from subsurface accumulation (source 2). If the presence and location of such an accumulation of hydrocarbons can be identified, it is possible that the hydrocarbons from such an accumulation can be extracted.
[0036] [0036] Figure 2 represents a flow diagram of a method 200 to determine the (i) location of an accumulation of subsurface hydrocarbons, and (ii) the source facies and the thermal maturity of the associated hydrocarbons sampled from an infiltration of seabed. According to the method, in block 202, the stochastic distribution of the isotopologists of a hydrocarbon species of interest is determined for a given mass isotopic signature for that species. Determining the stochastic distribution of isotopologists requires knowledge of the mass isotope signature of the species from which it is derived. For example, determining the stochastic distribution of isotopologists for methane and calculating the stochastic distribution require the 13C and D methane signatures. The isotopic signature of hydrocarbon gases, which are stored in a subsurface accumulation or which are present in infiltrations, may reflect the isotopic signature of the gas generated by the source rock. As such, this signature can be concomitantly determined during the characterization of the hydrocarbons present in an infiltration and replaced directly in the calculation of the stochastic distribution. There may be occasions, however, when the isotopic signature of the gases can be altered, due to various processes, such as mixing with biogenic gas. In such examples, correction schemes, such as that proposed by Chung et al., “Origin of gaseous hydrocarbons in subsurface environment: theoretical considerations of carbon isotope distribution”, Chemical Geology, v. 71, p. 97 - 104 (1988), can be given to unfold such contributions and achieve the initial main isotope signature, which should be used in the calculation of the stochastic distribution.
[0037] [0037] In block 204, ab-initio calculations are made to determine the theoretical grouped isotopic signature of each isotopologist of the hydrocarbon of interest. The ab-initio calculations, conducted in molecular modeling, focus on a method to calculate the abundances of all isotopologists for any given hydrocarbon in a thermally balanced population of isotopologists. This method incorporates three linked algorithms. The first of these algorithms is capable of selecting a subset of isotopologists of any given species that can only define the mass isotopic composition of a given population of molecules (for example, H / D ratio, including contributions from all isotopologists). The second algorithm is used to define the set of isotopic exchange reactions among all isotopologists, for which the calculation of an equilibrium constant is required. Finally, the third algorithm is used to calculate the selected equilibrium constants of the molecular properties, such as molecular mass, rotational constants, vibrational frequencies, disharmonicity corrections and vibration-rotation coupling constants. The latter parameters are calculated using the first high-level principle calculations discussed below (eg, grouping singlet, doublet and triplet excitation approximation, using a very large set of consistent-correlation basis).
[0038] [0038] If methane, the main chemical component of natural gases, is used as an example, it is possible to investigate the formation potential of the grouped double substituted isotopologist 13CH3D, and the double substituted isotopologist 12CH2D2. As shown in Figure 3, where the thermal increase of various concentrations of 13CH3D is plotted versus temperature, the signatures of the modeled clustered isotopes of 13CH3D and 12CH2D2 vary with temperature. In fact, it is possible to calculate the thermal dependence for any isotopologist of any hydrocarbon species that has received the isotopic signature.
[0039] [0039] If the isotopologist 13CH3D is considered, its total relative abundance in mass methane must be controlled by (a) randomly populated processes independent of temperature (stochastic distribution) and (b) isotopic exchange of thermal equilibrium. The latter process is controlled or dependent on the surrounding temperature. These processes can be determined by first-principle quantum mechanical calculations (such as Couple-cluster Singles, Doubles and Triples, CCSD (t) or Functional Density Theory (DFT) calculations), to investigate the formation of 13CH3D, its thermodynamic balance and dependence of the temperature.
[0040] [0040] The concentration of the double substituted methane isotopologists N (13CH3D] 0 relative to the total concentration of methane N [CH4] 0 in a stochastic distribution can be calculated for any given relative concentration of 13C and D (N [13C) and N [D)] by equation (1) below:
[0041] [0041] Any deviation between this modeled concentration and the measured concentration for a given isotopologist (discussed below) is merely a function of the temperature at which the species was stored, assuming that it achieves isotopic equilibrium for a given temperature through geological time scales. The temperature-dependent isotopic exchange of any species is governed by thermal equilibrium with a known equilibrium constant, Keq (T), and can be described for the above examples by the reaction: 13CH4 + CH3D ↔ CH4 + 13CH3D (Keq) (2)
[0042] [0042] If the temperature-dependent difference between a stochastic and non-stochastic distribution is given by N [13CH3D] t, then, after obtaining thermal equilibrium, the concentration of isotopologists involved in equation (2) can be described by following equations: N [13CH3D] = N [13CH3D] 0 + N [13CH3D] t (3) N [13CH4] = N [13C] - N [13CH3D] t (4) N [CH3D] = N [D] - N [13CH3D] t (5) N [CH4] = N [CH4] 0 - (N [13CH4] -N [13CH3D] t] - (N [D] -N [13CH3D] t) - N [D] - (N [13CH3D] 0+ N [13CH3D] t) (6)
[0043] [0043] By equations (3) - (6) it is possible to describe an equilibrium constant for the initial reaction given in equation (2). The equilibrium constant can then be calculated for any given temperature by high-level quantum chemistry calculations and using the Urey Model of the product and reagent partition function.
[0044] [0044] The total abundance of N [13CH3D] can, therefore, be calculated by the knowledge of Keq (T), N [13C] and N [D], combining statistical and thermal equilibrium effects at any given temperature.
[0045] [0045] The example described above can be applied to determine the expected abundance of any isotopologist in which measurements can be made, where the error associated with the measurement does not exceed the deviation from a purely etochastic distribution for a given temperature and mass isotopic signature. primary use of the hydrocarbon species of interest.
[0046] [0046] Returning to Figure 2, in block 206, the grouped isotopic signature of the hydrocarbon isotopologists of interest is measured. The measurement of the absolute abundance of isotopologists for any given hydrocarbon requires knowledge of the molecular mass in which they are present and, consequently, requires knowledge of the real identity of each possible isotopologist for that species. The measurement of the abundance of each isotopologist can be conducted using multiple techniques, such as mass spectrometry and / or leiser-based spectroscopy.
[0047] [0047] In block 208, the excess of temperature-dependent grouped isotopes is compared with the previously determined stochastic distribution. Following the measurement of the absolute abundance of co-existing isotopologists, it must be possible to integrate the modeled temperature dependence of isotopologists with measured concentrations to (1) differentiate between hydrocarbons that originate directly from a source rock and those that have escaped an accumulation of subsurface, and (2) determine the current equilibrium storage temperature of the reservoir species, before escaping to the surface.
[0048] [0048] The differentiation between direct infiltration of a source rock of hydrocarbon leakage from a subsurface accumulation requires consideration of the grouped isotopic signatures, which may result from the two infiltration models. Hydrocarbons that have migrated directly from a source rock may (i) retain a stochastic clustered isotopic signature that has received insufficient time for a thermal contribution to the "grouping" of multiple substituted isotopologists, or (ii) exhibit an inconsistent clustered isotope signature, which arises as a result of the variability in the isotope exchange rate of individual isotopologists. In contrast, hydrocarbons that derive from an accumulation of subsurface will retain an accumulated isotope signature, which most consistently reflects the temperature at which they were stored on the subsurface. This non-kinetic control over isotopic exchange reactions in hydrocarbon isotopologists that originate from a subsurface accumulation arises as a result of the inherently long residence times of the subsurface hydrocarbons. Aspects of the methodologies and techniques described can thus identify the presence of subsurface hydrocarbon accumulations. Once identified, it is possible to apply a geothermal gradient appropriate to the equilibrium storage temperature, to estimate the location (depth) within the subsurface where the associated hydrocarbon accumulation resides.
[0049] [0049] Another aspect of the described methodologies and techniques is to characterize the source rock from which the hydrocarbon originated. As represented by block 210, the results of the previous parts of the method are integrated with known geochemical substitutes, which can be used concurrently to determine the source facies by estimating the biomarker distribution of the associated hydrocarbons and estimates of thermal maturity through isotopic characterization of the associated hydrocarbons. More specifically, by knowing the biomarker distribution of different sources of organic material and how it can be genetically linked to the hydrocarbons that are produced from such sources, it is possible to determine the source facies from which the accumulated hydrocarbon was derived. Furthermore, by knowing how the isotopic signature of hydrocarbons of organic matter from different sources develops during maturation, it is possible to determine the thermal maturity of the source rock from which the hydrocarbons are derived. The results of method 200 can also be integrated with conventional exploration or expectation assessment technologies to confirm or not to risk the presence and / or location of a hydrocarbon accumulation and to assess the potential migration paths from the source rock to the infiltration. Such technologies may include seismic reflection, high resolution seismic imaging, acoustic, basin modeling and / or probabilistic or statistical assessments. By integrating these technologies, various characteristics of the accumulation can be estimated, such as hydrocarbon volume, type of hydrocarbon (eg, oil vs. gas) and the like. Once an accumulation of hydrocarbons has been identified and located, the hydrocarbons therein can be extracted or otherwise produced using known hydrocarbon control principles.
[0050] [0050] An alternative to concomitantly determine the temperature of the reservoir, source facies and thermal maturity may involve statistical regression analysis, to converge on the temperature dependent equilibrium constant and unusual isotopes, such as 13C and D, which may be unique for the relative concentrations reported for multiple coexisting isotopologists.
[0051] [0051] Figure 4 is a block diagram of a computer system 400, which can be used to perform some or all of the aspects and methodologies described. A central processing unit (CPU) 402 is coupled to the 404 system bus. CPU 402 can be any general purpose CPU, although other types of 402 CPU architectures (or other exemplary 400 system components) can be used, provided that CPU 402 (and other system components 400) supports inventive operations as described herein. The CPU 402 can execute the various logic instructions according to several exemplary embodiments. For example, CPU 402 can execute machine-level instructions to perform processing according to the operating flow described above. One or more graphics processing units (GPU) 414 can be included and used as known in the art.
[0052] [0052] Computer system 400 may also include computer components, such as random access memory (RAM) 406, which may be SRAM, DRAM, SDRAM or similar. Computer system 400 may also include read-only memory (ROM) 408, which may be PROM, EPROM, EEPROM or similar. RAM 406 and ROM 408 hold user and system data and programs, as is known in the art. Computer system 400 may also include an input / output (I / O) adapter 410, a communications adapter 422, a user interface adapter 424 and a monitor adapter 412. The I / O adapter 410, the adapter User interface 424 and / or communications adapter 422 may, in certain embodiments, enable the user to interact with computer system 400 in order to enter information.
[0053] [0053] The I / O 410 adapter preferably connects a storage device (s) 412, such as one or more of hard disk, compact disk drive (CD, floppy drive, magnetic tape drive etc.) with the system computer 400. The storage device (s) can be used when the RAM 406 is insufficient for the memory requirements associated with storage data for operations of carrying out the present techniques. data storage of computer system 400 can be used to store information and / or other data used or generated as described here The communications adapter 422 can couple computer system 400 with a network (not shown), which can enable information is entered into and / or issued by the 400 system, via the network (for example, the internet or other wide-area network, an area-local network, a public or private switched telephone network, a wireless network , any combination of the precedents). User interface adapter 424 couples user input devices, such as a 428 keyboard, pointing device 426 and the like, to computer system 400. Monitor adapter 418 is driven by CPU 402 to control, via a drive monitor 416, the display of a monitor device 420. Information and / or representations pertaining to a part of a supply chain project or shipping simulation, such as display data corresponding to a physical or financial property of interest, may thereby be displayed, in accordance with certain exemplary embodiments.
[0054] [0054] The architecture of the 400 system can be varied as desired. For example, any suitable processor-based device can be used, including, without limitation, personal computers, laptop computers, computer workstations and multi-processor servers. In addition, the embodiments can be implemented in application-specific integrated circuits (AICs) or very large-scale integrated circuits (VLSI). In fact, people of ordinary skill in the art can use any number of suitable structures, capable of performing logical operations according to the embodiments.
[0055] [0055] Figure 5 shows a representation of a machine-readable logic or code 500, which can be used or executed with a computing system, such as computing system 400. In block 502, code is provided to determine an expected concentration of isotopologists of a hydrocarbon species. In block 504, a code is provided to model, using high-level ab initio calculations, a temperature dependence of isotopologists present in the sample. In block 506, a code is provided to measure a grouped isotopic signature of the isotopologists present in the sample. In block 508, a code is provided to compare the grouped isotopic signature with the expected concentration of isotopologists. In block 510, a code is provided to use said comparison to determine whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample escaped from a subsurface accumulation. When executed or applied with a computer system, such as computer system 400, such code is configured to determine the presence and location of a subsurface hydrocarbon accumulation in a naturally occurring substance sample. The code effecting or executing other details of the aspects and methodologies described can be provided as well. This additional code is represented in Figure 5 as block 512 and can be placed anywhere within code 500, according to computer code programming techniques.
[0056] [0056] Illustrative, non-exclusive examples of methods and products according to the present description are presented in the following non-enumerated paragraphs. It is within the scope of the present description that an individual step in a method narrated here, including the following paragraphs enumerated, may additionally or alternatively be referred to as a "step to" carry out the aforementioned action.
[0057] [0057] A method of determining the presence and location of a subsurface hydrocarbon accumulation in a naturally occurring substance sample, the method comprising: determine an expected concentration of isotopologists of a hydrocarbon species; model, using high-level ab initio calculations, an expected temperature dependence of the isotopologists present in the sample; measure a grouped isotopic signature of the isotopologists present in the sample; compare the grouped isotopic signature with the expected concentration of isotopologists; to determine, using this comparison, whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample escaped a subsurface accumulation; determine the current equilibrium storage temperature of the hydrocarbon species in the subsurface accumulation before escaping to the surface; and determine a location for subsurface accumulation.
[0058] [0058] A1. The method of paragraph A, in which determining an expected concentration of isotopologists includes determining a stochastic distribution of isotopologists of the hydrocarbon species for a given mass isotopic signature for the species.
[0059] [0059] A2. The method of any of the preceding paragraphs A - A1, further comprising:
[0060] [0060] where the given mass isotopic signature of the hydrocarbon species was altered by secondary isotope exchange processes or by mixing, applying a correction scheme to arrive at an initial primary isotopic signature, representative of what was produced by source rock.
[0061] [0061] A3. The method of any of the preceding paragraphs A - A2, in which the location comprises a depth.
[0062] [0062] A4. The method of any of the preceding paragraphs A - A3, where determining a location includes applying a thermal gradient to an equilibrium storage temperature of subsurface accumulation.
[0063] [0063] A5. The method of any of the preceding paragraphs A - A4, further comprising determining a source facies from which the hydrocarbons from subsurface accumulation were derived.
[0064] [0064] A6. The method of any of the preceding paragraphs A - A5, in which determining a source facies includes generically linking the biomarker distribution of the sources of organic matter to hydrocarbons produced from the source facies.
[0065] [0065] A7. The method of any of the preceding paragraphs A - A6, further comprising determining the thermal maturity of the source rock from which the hydrocarbons of subsurface accumulation are derived.
[0066] [0066] A8. The method of any of the preceding paragraphs A - A7, in which determining thermal maturity includes using knowledge of how the isotopic signature of hydrocarbons from organic matter from different sources develops during maturation.
[0067] [0067] A9. The method of any of the preceding paragraphs A - A8, also comprising determining the precise location of the subsurface hydrocarbon accumulation, using a geophysical imaging technique.
[0068] [0068] A10. The method of any of the preceding paragraphs A -A9, in which the geophysical imaging technique is seismic reflection.
[0069] [0069] B. A Method of determining the presence and location of an accumulation of subsurface hydrocarbon, comprising: obtain a hydrocarbon sample from a spring; analyzing the hydrocarbon sample to determine its geochemical signature, said analysis including measuring the distribution of isotopologists for a hydrocarbon species present in the hydrocarbon sample; determine a stochastic distribution of isotopologists for the hydrocarbon species; determine the deviation of the measured distribution of isotopologists from the stochastic distribution of isotopologists for the hydrocarbon species; determine the origin of the hydrocarbon sample; determine the storage temperature of the hydrocarbon species, when the source of the hydrocarbon sample is an accumulation of hydrocarbon; and determine the location of the hydrocarbon accumulation by the storage temperature.
[0070] [0070] B1. The method of paragraph B, in which the geochemical signature comprises one or more of mass composition, isotopic signatures, molecular geochemistry and isotope / isotopologist chemistry grouped.
[0071] [0071] B2. The method of any of the preceding paragraphs B - B1, in which the hydrocarbon species is methane.
[0072] [0072] B3. The method of any of the preceding paragraphs B - B2, wherein the location of the hydrocarbon accumulation includes a depth.
[0073] [0073] B4. The method of any of the preceding paragraphs B - B3, in which the origin of the hydrocarbon sample is a facies of source.
[0074] [0074] B5. The method of any of the preceding paragraphs B - B4, further comprising identifying the source facies associated with the hydrocarbon sample.
[0075] [0075] B6. The method of any of the preceding paragraphs B - B5, further comprising determining the thermal maturity of a source rock associated with the hydrocarbon sample.
[0076] [0076] B7. The method of any of the preceding paragraphs B - B6, further comprising confirming the presence of the hydrocarbon accumulation site using one or more of the following: seismic, acoustic, probabilistic reflections, of the presence and location of the hydrocarbon accumulation, and a basin model.
[0077] [0077] B8. Method of any of the preceding paragraphs B - B7, further comprising producing hydrocarbons from subsurface accumulation.
[0078] [0078] C. Method of determining the presence of an accumulation of subsurface hydrocarbon from a naturally occurring substance sample, the method comprising: determine the expected concentration of isotopologists of a hydrocarbon species; modeling, using high-level ab initio calculations, an expected temperature dependence of the isotopologists present in the sample; measure a grouped isotopic signature of the isotopologists present in the sample: compare the grouped isotopic signature with the expected concentration of isotopologists; to determine, using this comparison, whether the hydrocarbons present in the sample escaped a subsurface accumulation, thereby determining the presence of subsurface accumulation;
[0079] [0079] C1. The method of paragraph C, further comprising: determine the current equilibrium storage temperature of the hydrocarbon species from subsurface accumulation before escaping to the surface; and determine the location of subsurface accumulation.
[0080] [0080] A computer system configured to determine the presence and location of an accumulation of subsurface hydrocarbon from a naturally occurring substance sample, the computer system comprising: a processor; and a machine-readable, tangible storage medium that stores machine-readable instructions for execution by the processor, machine-readable instructions including: code to determine an expected isotopologist concentration of a hydrocarbon species, code to model, using high-level ab initio calculations, an expected temperature dependence of isotopologists present in the sample, code to measure a grouped isotopic signature of the isotopologists present in the sample, code to compare the grouped isotopic signature with the expected concentration of isotopologists, and code to determine, using said comparison, whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample escaped from subsurface accumulation.
[0081] [0081] D1. The system in paragraph D, where the code for determining an expected concentration of isotopologists includes code for determining a stochastic distribution of isotopologists of the hydrocarbon species for a given mass isotopic signature for the species.
[0082] [0082] D2. The system of any of the preceding paragraphs D - D1, further comprising code to determine the current equilibrium storage temperature of the hydrocarbon species in the subsurface accumulation, to escape to the surface.
[0083] [0083] D3. The system of any of the preceding paragraphs D - D2, further comprising code for determining the location of subsurface accumulation, applying a thermal gradient at an equilibrium storage temperature of subsurface accumulation.
[0084] [0084] D4. The system of any of the preceding paragraphs D - D3, further comprising code to determine the source facies from which the subsurface accumulation hydrocarbons derived.
[0085] [0085] E. A method of determining the presence and location of an accumulation of subsurface hydrocarbon and the origin of associated hydrocarbons, collected from a surface spring, comprising: integrate molecular modeling to determine the expected concentration of isotopologists of a hydrocarbon species of interest; measure the concentration of isotopologists of the hydrocarbon species of interest; conduct a statistical regression analysis, to converge on a temperature dependent equilibrium constant and a unique isotopic signature for the absolute concentrations measured for multiple coexisting isotopologists; and for hydrocarbons collected from the surface source, determine at least one of: storage temperature, a font facies and thermal maturity of source rock associated with it.
[0086] [0086] E1. The method of paragraph E, further comprising integrating at least one storage temperature, the source facies and the thermal maturity of the source rock associated with the hydrocarbons collected from the surface spring with pre-drilling basin burial history models, for calibrate an associated basin model.
[0087] [0087] The methodologies and techniques described may be susceptible to various modifications and alternative forms and the embodiments discussed here are not limiting examples. In reality, the methodologies and techniques described include all alternatives, modifications and equivalents, falling within the spirit and scope of the attached claims.

权利要求:
Claims (15)
[0001]
Method for determining the presence and location of an accumulation of subsurface hydrocarbon in a sample of naturally occurring substance, said method characterized by the fact that it comprises: determine an expected concentration of isotopologists of a hydrocarbon species; modeling, using high-level ab initio calculations, a temperature dependence expected from isotopologists present in the sample; measure a grouped isotopic signature of the isotopologists present in the sample; integrate the modeled temperature dependence of the isotopologists present in the sample; compare the grouped isotopic signature with the expected concentration of isotopologists; determine, using said comparison, and using any deviation between the expected concentrations and measurements of isotopologists, whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample escaped from a subsurface accumulation; determine, using said comparison, the current equilibrium storage temperature of the hydrocarbon species of the subsurface accumulation before escaping to the surface; and estimate the location of subsurface accumulation by applying a geothermal gradient of equilibrium storage temperature.
[0002]
Method according to claim 1, characterized by the fact that determining an expected concentration of isotopologists includes determining a stochastic distribution of isotopologists of the hydrocarbon species for a given mass isotopic signature for the species.
[0003]
Method according to claim 2, characterized by the fact that it further comprises: where the given mass isotopic signature of the hydrocarbon species was altered by secondary isotope exchange processes or by mixing, apply a correction scheme to arrive at an initial primary isotopic signature, representative of what was produced by the source rock.
[0004]
Method according to claim 1, characterized by the fact that the location comprises a depth.
[0005]
Method according to claim 1, characterized by the fact that it further comprises determining facies of source from which the hydrocarbons in the subsurface accumulation were derived.
[0006]
Method according to claim 5, characterized in that determining source facies includes generically linking the biomarker distribution of sources of organic matter with the hydrocarbons produced from the source facies.
[0007]
Method according to claim 1, characterized by the fact that it further comprises determining a thermal maturity of the source rock from which the hydrocarbons of subsurface accumulation are derived.
[0008]
Method according to claim 1, characterized by the fact that it also comprises determining a location of the subsurface hydrocarbon accumulation, using a geophysical imaging technique.
[0009]
Method according to claim 8, characterized by the fact that the geophysical imaging technique is seismic reflection.
[0010]
Method according to claim 1, characterized in that it further comprises obtaining a hydrocarbon sample from a spring.
[0011]
Method according to claim 10, characterized by the fact that it comprises confirming the presence and location of the hydrocarbon accumulation, using one or more of the following: seismic, acoustic and probabilistic reflection estimates, the presence and location of the hydrocarbon accumulation , and a basin model.
[0012]
Method according to claim 10, characterized by the fact that it also comprises producing hydrocarbons from the subsurface accumulation.
[0013]
Computer system configured to determine the presence and location of a subsurface hydrocarbon accumulation in a naturally occurring substance sample, said computer system characterized by the fact that it comprises: a processor; and a machine-readable, tangible storage medium that stores machine-readable instructions for execution by the processor, machine-readable instructions including: code to determine an expected isotopologist concentration of a hydrocarbon species, code to model, using high-level ab initio calculations, an expected temperature dependence of isotopologists present in the sample, code to measure a grouped isotopic signature of the isotopologists present in the sample, code to interpret the modeled temperature dependence of isotopologists with the measured concentrations, and to compare the grouped isotopic signature with the expected concentration of isotopologists, code to determine, using said comparison, and using deviations between the expected and measured isotopologists, whether the hydrocarbons present in the sample originate directly from a source rock or whether the hydrocarbons present in the sample escaped from a subsurface accumulation, code to determine, using said comparison, the current equilibrium storage temperature of hydrocarbon species in subsurface accumulation before escaping to the surface, and code to estimate a location of subsurface accumulation, applying a geothermal gradient at equilibrium storage temperature.
[0014]
System according to claim 13, characterized by the fact that the code for determining an expected concentration of isotopologists includes code for determining a stochastic distribution of isotopologists of the hydrocarbon species for a given mass isotopic signature for the species.
[0015]
System according to claim 13, characterized by the fact that it also comprises code to determine source facies from which the hydrocarbons of subsurface accumulation were derived.

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法律状态:
2018-12-11| B06F| Objections, documents and/or translations needed after an examination request according [chapter 6.6 patent gazette]|

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2019-12-10| B06U| Preliminary requirement: requests with searches performed by other patent offices: procedure suspended [chapter 6.21 patent gazette]|

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2021-02-23| B09A| Decision: intention to grant [chapter 9.1 patent gazette]|

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