A deep-time earth system carbon flux estimation method and system

Abstract

The present application belongs to the technical field of geochemistry, and particularly relates to the estimation of the carbon flux of the earth system, and especially relates to a method and system for estimating the carbon flux of the deep-time earth system. The method for estimating the carbon flux of the deep-time earth system provided by the present application solves the four defects in the traditional technology caused by the fixed carbon pool assumption, the neglect of the atmospheric / biosphere carbon content, the isotopic error, and the failure to consider the fractionation effect through dynamic carbon pool segmentation, the inclusion of multi-sphere isotopic composition, and the correction of fractionation effect. The high-precision and verifiable model framework not only improves the scientificity of the deep-time carbon cycle research, but also provides a key tool for analyzing the climate evolution mechanism in the geological history period and predicting the future climate change trend, and has important theoretical innovation and practical application value.

Description

Technical Field

[0001] This invention belongs to the field of geochemistry technology, specifically relating to the estimation of carbon flux in the Earth system, and particularly to a method and system for estimating carbon flux in the deep-time Earth system. Background Technology

[0002] In the field of geological research, the assessment of the deep-time Earth system carbon cycle and the estimation of carbon flux occupy a crucial position. The carbon cycle in the Earth system involves multiple spheres, including the atmosphere, ocean, and biosphere, and is a complex and dynamic process. A deeper understanding of this process not only helps us comprehend the Earth's evolutionary history but also provides important evidence for predicting future climate change trends. For example, by studying the carbon cycle in past geological periods, we can understand the patterns of climate change at different times, thus providing historical references for addressing current global climate change.

[0003] Current methods for assessing the carbon cycle in the deep-time Earth system treat the atmosphere, ocean, and biosphere as a single subsystem (Mo), i.e., the surface system. They quantify carbon injection (including volcanic eruptions, weathering and decomposition of carbonate rocks and organic matter) and carbon fixation (including carbon sequestration through photosynthesis by plants and plankton, and diagenesis of carbonate rocks) caused by geological processes during the carbon cycle. Based on the law of conservation of carbon mass, a carbon cycle assessment model is established to estimate deep-time carbon fluxes. This method is widely used in estimating carbon fluxes during various geological periods of the Phanerozoic Eon, especially during periods of intense carbon disturbance (such as large igneous provinces, rapid decomposition of natural gas hydrates, and ocean anoxic events).

[0004] In practical deep-time carbon flux estimation, existing technologies treat the Earth's surface system, including the atmosphere, ocean, and biosphere, as a whole. Since the carbon content of the surface system is much smaller than the total carbon content of the Earth system, and the carbon content of the atmosphere and biosphere is much smaller than the carbon content of the ocean, the following assumptions are often made during the estimation process: (1) The total carbon content of the surface system is taken as a constant; (2) The total carbon content of the surface system is equal to the carbon content of the ocean, ignoring the carbon content in the atmosphere and biosphere; (3) Stable carbon isotopes (δ¹⁸O) in the ocean are considered as a constant. 13 C o (4) The carbon isotopes in the carbon cycle process are directly imported into the carbon mass conservation model for calculation. In practical applications, this estimation method has exposed many problems. These problems seriously affect the accuracy and reliability of carbon flux estimation and urgently need to be solved, as follows: First, there's the problem of the assumption regarding the total carbon content of the Earth's surface system: Current technology treats the total carbon content of the Earth's surface system as a constant. However, throughout the Phanerozoic Eon, the total carbon content of the Earth's surface system was not static but dynamically changing over a considerable range. For example, during the Jurassic and Cretaceous periods, the total carbon content of the Earth's surface system was far greater than in the present day, exceeding twice the current level. During the ice-free period, ocean areas expanded significantly, and atmospheric carbon dioxide levels were also much higher than in other eras. Under these circumstances, treating the total carbon content of the Earth's surface system as a fixed value is clearly inconsistent with reality. This unreasonable assumption leads to an inability to accurately reflect the true changes in total carbon content during carbon flux estimation.

[0005] Second, the issue of neglecting atmospheric and biosphere carbon content: Current technologies, in estimating carbon flux, sometimes equate the total carbon content of the Earth's surface system with that of the oceans, thus ignoring the carbon content in the atmosphere and biosphere. However, the concentration of atmospheric carbon dioxide varied significantly throughout the Phanerozoic Eon. During the Triassic and Jurassic periods, especially during carbon disturbances, atmospheric carbon dioxide concentrations rose sharply, reaching 3000-4000 ppm, more than ten times the current atmospheric carbon dioxide concentration (400 ppm) and pre-industrial levels (270 ppm). Simultaneously, carbon isotope variations were also significant, ranging from -10 to -3‰. Such high carbon dioxide concentrations and pronounced carbon isotope characteristics clearly demonstrate that atmospheric carbon dioxide constitutes an indispensable and crucial component of the total carbon content in the Earth's surface system. Ignoring the carbon content of the atmosphere and biosphere in carbon flux estimation inevitably leads to an underestimation of the total carbon content in the Earth's surface system, resulting in significant deviations in carbon flux estimation.

[0006] Third, the issue of carbon isotope equivalence between ocean and surface systems: Current technologies still struggle with equivalence between stable carbon isotopes (δ¹⁸O) in the ocean. 13 C o Equating the stable carbon isotopes in the ocean with those in the Earth's surface system is an unreasonable approach. In reality, the Earth's surface system is composed of three main components: the ocean, the atmosphere, and biological organisms, and these three components have significantly different isotopic composition. Taking the Earth today as an example, the carbon isotopes of the ocean, atmosphere, and biological organisms are 0‰, -7‰, and -25‰, respectively, showing a clear difference in isotopic composition. Since the relative changes in the carbon content of these three components directly cause changes in the carbon isotopes of the Earth's surface system, simply equating the stable carbon isotopes in the ocean (δ¹⁸O) with the carbon isotopes of the surface system is not a sound approach. 13 C o Equating carbon isotopes with those of the Earth's surface system is completely inappropriate. This erroneous equivalence introduces significant errors when using carbon isotopes for carbon cycle research and carbon flux estimation.

[0007] Fourth, the carbon isotope fractionation effect was not considered: During the Earth's carbon cycle, carbon isotope fractionation occurs during both carbon output and fixation; for example, fractionation occurs when atmospheric carbon dioxide dissolves in water. However, previous carbon flux estimates did not adequately account for this fractionation effect. This omission of a crucial factor leads to an overestimation of carbon inputs and can easily result in misidentification of carbon emission sources. This not only affects the correct understanding of the carbon cycle process but also renders related policies and decisions based on these estimates lacking in scientific rigor and accuracy, hindering effective responses to environmental and resource issues related to the carbon cycle.

[0008] In summary, existing deep-time Earth system carbon flux estimation techniques suffer from a series of problems that severely affect the accuracy and scientific rigor of these estimates. These issues not only lead to biased understandings of the carbon cycle process but may also cause misleading conclusions in geological studies and climate change predictions based on these estimates. Therefore, there is an urgent need in this field to improve and innovate research methods, establish more scientific and accurate carbon cycle assessment models, and more realistically reflect the history and current state of the Earth system's carbon cycle, providing reliable data support for geological scientific research. Summary of the Invention

[0009] This invention aims to establish a more scientific and accurate method and system for estimating deep-time Earth system carbon flux by improving and innovating research methods, so as to more realistically reflect the history and current status of the Earth system's carbon cycle and provide reliable data support for geological science research.

[0010] In view of this, the present invention provides a method for estimating carbon flux in the deep-time Earth system, comprising the following steps: S1, Segmentation of the Earth's Surface Carbon Pool: The Earth's surface carbon pool is segmented into the atmospheric carbon pool, the marine carbon pool, and the biosphere carbon pool, and M is used. S M A M O and M B These represent the carbon content of the surface system carbon pool, the atmospheric carbon pool, the marine carbon pool, and the biosphere carbon pool, respectively. Where M... S M A M O and M B The relationship between them satisfies Formula 1: M S =M O +M A +M B ; S2, incorporating carbon isotope composition: Incorporating carbon isotope composition into the carbon cycle of the Earth's surface system yields Formula 2: M S *δ 13 C S =M O *δ 13C O +M A *δ 13 C A +M B *δ 13 C B , where δ 13 C S δ 13 C O δ 13 C A and δ 13 C B The carbon isotope composition of the Earth's surface system, ocean system, atmosphere, and biosphere, respectively. S3, Establishing a deep-time Earth system carbon flux estimation model: Based on the law of conservation of mass and combined with the isotopic fractionation effect during the carbon injection process into the Earth's surface system, formula three for estimating deep-time Earth system carbon flux is constructed: ; in, The total carbon flux of the deep-time Earth system; F vm F carb F org These are the carbon emissions from volcanic activity, net weathering of carbonate rocks, and net emissions of organic carbon, respectively. δ 13 C vm δ 13 C carb δ 13 C org These are the carbon isotope compositions of carbon emitted by volcanic activity, carbon isotope compositions of carbon from net weathering of carbonate rocks, and carbon isotope compositions of carbon from net organic emissions, respectively. , These are the isotopic fractionation coefficients of atmospheric carbon dioxide dissolved in water and carbonate rock deposition processes, respectively. S4, Calculate the total carbon flux of the deep-time Earth system. Determine the start and end times for estimating the total carbon flux of the deep-time Earth system. This yields the start and end times for estimating the total carbon flux of the deep-time Earth system. Then, calculate M at these two different times using Formula 2. S *δ 13 C S The value of this is used to obtain the total carbon flux of the deep-time Earth system. The value of , where, M at the termination time and the start time S *δ 13 C S Difference of values ​​divided by time interval; S5, calculate the carbon emissions F from volcanic activity according to Formula 3. vm The value is obtained from the total carbon flux of the deep Earth system. Carbon emissions F from volcanic activity in the deep Earth system vm Net weathering of carbonate rocks in deep Earth systems, F carb And the net emissions of organic carbon F in the deep Earth system org This constitutes a set of deep-time Earth system carbon flux estimates.

[0011] Furthermore, in Formula 3, the net weathering amount F of the carbonate rock carb = F wcarb - F bcarb , of which F bcarb F represents the amount of carbonate rock deposits. wcarb This represents the amount of carbonate rock dissolved.

[0012] Furthermore, in Formula 3, the F org =F worg -F borg -F' borg , of which F worg F represents the amount of organic matter decomposed. borg For marine organic carbon deposition, F' borg This represents the amount of organic carbon deposited on land.

[0013] Furthermore, in Formula 1 and Formula 2, the carbon content M of the atmospheric carbon pool A =2.13* p CO2; among which, p CO2 is the concentration of carbon dioxide in the atmosphere.

[0014] Furthermore, the carbon content M of the marine carbon pool O The calculation method is as follows: M O =12*m seawater *DIC; Where, m seawater The mass of seawater in the Phanerozoic Eon; DIC stands for Total Dissolved Inorganic Carbon in the ocean.

[0015] Furthermore, the total dissolved inorganic carbon (DIC) content of the ocean is calculated as follows:

[0016] [CO2] represents the carbon dioxide content in seawater; K1 * K2 * K1 is the equilibrium constant for a chemical reaction. * ≈10-5.9, K2* ≈10-8.9; H + This represents the concentration of hydrogen ions in seawater.

[0017] Furthermore, the carbon dioxide content [CO2] in seawater is calculated as follows: [CO2]=K o * p CO2; Among them, K o is the Henry's constant.

[0018] Furthermore, in Formula 1 and Formula 2 above, the carbon content M of the biosphere carbon pool B The calculation method is as follows: M B =610PgC, where 610 is the carbon storage value of the biosphere carbon pool and PgC is the unit of measurement.

[0019] Furthermore, in Formula 2, the δ 13 C B The value of δ 13 C org The values ​​of δ are equal, 13 C A The value of δ 13 C CO2 The values ​​of δ are equal. 13 C CO2 and δ 13 C O The calculation method is as follows: ; ; in, This represents the carbon isotopic composition of carbonate rocks, where V represents the fractionation that occurs during the precipitation of carbonate ions in seawater.

[0020] A deep-time Earth system carbon flux estimation system is provided, which uses the above-mentioned estimation method to estimate the deep-time Earth system carbon flux.

[0021] Compared to existing technologies, the deep-time Earth system carbon flux estimation method provided by this invention systematically solves the four major defects of traditional technologies (fixed carbon pool assumption, neglect of atmospheric / biosphere carbon content, isotopic equivalence error, and failure to consider fractionation effect) through dynamic carbon pool segmentation, inclusion of multi-sphere isotopic composition, and correction for fractionation effect. Its high-precision and verifiable model framework not only enhances the scientific rigor of deep-time carbon cycle research, but also provides a key tool for analyzing climate evolution mechanisms in geological history and predicting future climate change trends, demonstrating significant theoretical innovation and practical application value. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the carbon cycle pathway in the deep-time surface system; Figure 2 This is a comparison chart of the estimation results obtained by using the deep-time Earth system carbon flux estimation method described in this invention and the traditional estimation method to estimate the carbon flux of the Early Jurassic oceanic anoxic event. Detailed Implementation

[0023] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0024] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0025] In view of the various problems exposed by traditional deep-time Earth system carbon flux estimation models, this invention proposes a novel deep-time Earth system carbon flux estimation method, which takes into account the carbon content of the Earth's surface systems such as the atmosphere, ocean, and organisms into the Earth's carbon cycle system. By calculating the carbon content of these three elements in the surface system and determining their carbon isotopic composition, and focusing on the fractionation effect in the carbon cycle process of the surface system, the deep-time Earth system carbon flux can be accurately calculated.

[0026] Specifically, this invention provides a method for estimating carbon flux in the deep-time Earth system, comprising the following steps: S1, Segmentation of the Surface System Carbon Pool: The deep-time surface system is divided into three parts: the ocean, the atmosphere, and the biosphere. This means the surface system carbon pool is segmented into an atmospheric carbon pool, a marine carbon pool, and a biosphere carbon pool, and M is used as the basis for this segmentation. S M A M O and M B These represent the carbon content of the Earth's surface carbon pool, atmospheric carbon pool, marine carbon pool, and biosphere carbon pool, respectively, where M S M A M O and M B The relationship between them satisfies Formula 1: M S =MO +M A +M B ; S2, incorporating carbon isotope composition: Incorporating carbon isotope composition into the carbon cycle of the Earth's surface system yields Formula 2: M S *δ 13 C S =M O *δ 13 C O +M A *δ 13 C A +M B *δ 13 C B , where δ 13 C S δ 13 C O δ 13 C A and δ 13 C B The carbon isotope composition of the Earth's surface system, ocean system, atmosphere, and biosphere, respectively. S3. Establishing a deep-time Earth system carbon flux estimation model: Based on the law of conservation of mass and combined with the isotopic fractionation effect during the carbon injection process into the Earth's surface system, Formula 3 for estimating deep-time Earth system carbon flux is constructed. Formula 3 is as follows: ; in, The total carbon flux of the deep-time Earth system; F vm F carb F org These are the carbon emissions from volcanic activity, net weathering of carbonate rocks, and net emissions of organic carbon, respectively. δ 13 C represents the corresponding carbon isotope composition, specifically δ 13 C vm δ 13 C carb δ 13 C org These are the carbon isotope compositions of carbon emitted by volcanic activity, carbon isotope compositions of carbon from net weathering of carbonate rocks, and carbon isotope compositions of carbon from net organic emissions, respectively. , These are the isotopic fractionation coefficients of atmospheric carbon dioxide dissolved in water and carbonate rock deposition processes, respectively. S4, determine the start and end times of the total carbon flux estimation of the deep-time Earth system, thereby obtaining the start and end times of the total carbon flux estimation of the deep-time Earth system. Calculate the carbon isotopes in the surface system at the two different times (start and end) according to Formula 2.13 C) Content, i.e., calculating M at two different times. S *δ 13 C S The value of this is used to obtain the total carbon flux of the deep-time Earth system. The value of , where, M at the termination time and the start time S *δ 13 C S Difference of values ​​divided by time interval; S5, calculate the carbon emissions F from volcanic activity according to Formula 3. vm The value of this can be used to obtain the total carbon flux of the deep Earth system. Carbon emissions F from volcanic activity in the deep Earth system vm Net weathering of carbonate rocks in deep Earth systems, F carb And the net emissions of organic carbon F in the deep Earth system org This constitutes a set of deep-time Earth system carbon flux estimates.

[0027] Furthermore, in Formula 3, the net weathering amount F of the carbonate rock carb = F wcarb - F bcarb , of which F bcarb F represents the amount of carbonate rock deposits. wcarb This refers to the amount of carbonate rock dissolved. It should be noted that the F mentioned... bcarb and F wcarb The value can be obtained by consulting existing materials.

[0028] Furthermore, in Formula 3, the F org =F worg -F borg -F' borg , of which F worg F represents the amount of organic matter decomposed. borg For marine organic carbon deposition, F' borg For terrestrial organic carbon deposition, it should be noted that the F mentioned... worg、 F borg and F' borg The value can be obtained by consulting existing materials.

[0029] As some examples of the present invention, in Formula 1 and Formula 2, the carbon content M of the atmospheric carbon pool is... A The calculation method is as follows: M A =2.13* p CO2; in, pCO2 is the atmospheric carbon dioxide concentration, which is a known value.

[0030] As some examples of the present invention, the carbon content M of the marine carbon pool O The calculation method is as follows: M O =12*m seawater *DIC; Where, m seawater The mass of Phanerozoic seawater can be obtained by consulting existing documents; DIC stands for Total Dissolved Inorganic Carbon in the ocean.

[0031] Furthermore, the carbon content of the marine inorganic carbon pool mainly includes the carbon dioxide content [CO2] and bicarbonate ion concentration [HCO3] in seawater. - ], carbonate ion concentration [CO3 2- The total inorganic carbon content (DIC) of the ocean. Given pCO2, [CO2] can be calculated using Henry's Law. Then, by combining this with the ocean's pH value, the total inorganic carbon content (DIC) of the ocean can be calculated.

[0032] Specifically, the total inorganic carbon content (DIC) of the ocean can be calculated according to Formula 4, which is as follows: ; [CO2] represents the carbon dioxide content in seawater; K1 * K2 * K1 is the equilibrium constant for a chemical reaction. * ≈10 -5.9 K2 * ≈10 -8.9 ; H + This represents the concentration of hydrogen ions in seawater.

[0033] Furthermore, the carbon dioxide content [CO2] in seawater is calculated as follows: [CO2]=K o * p CO2; Among them, K o K is the Henry's constant. o ≈10 -1.5 .

[0034] As some examples of the present invention, in Formula 1 and Formula 2 above, the carbon content M of the biosphere carbon pool is... B The calculation method is as follows: M B=610PgC, where 610 is the carbon storage value of the biosphere carbon pool and PgC is the unit of measurement.

[0035] Based on the example above, given M A M O and M B Based on the value, M at different times can be calculated according to Formula 1. S The value of .

[0036] As some examples of the present invention, in the second formula, the δ 13 C B The value of δ 13 C org The values ​​of δ are equal, 13 C A The value of δ 13 C CO2 The values ​​are equal, where δ 13 C org The value of δ can be obtained by consulting existing data. 13 C CO2 and δ 13 C O The value can be calculated according to the calculation method described later.

[0037] Furthermore, given M A M O M B and M S The value of δ, and the known δ 13 C O δ 13 C A and δ 13 C B Based on this, δ can be calculated using Formula 2. 13 C S The value of .

[0038] Similarly, given δ 13 C O δ 13 C A and δ 13 C B The value of M, and M A M O and M B Based on the value of M, we can use Formula 2 to calculate M at different times. S *δ 13 C S The value of .

[0039] As some examples of the present invention, considering that the fractionation of surface carbon cycle isotopes mainly occurs between atmospheric carbon dioxide and the ocean, and between the ocean and carbonate rocks, the present invention, when estimating the carbon flux of the deep-time Earth system, primarily considers the fractionation between atmospheric carbon dioxide and the ocean, and between the ocean and carbonate rocks, and uses... , These represent the isotopic fractionation coefficients of atmospheric carbon dioxide dissolving in water and during carbonate rock deposition, respectively, and are incorporated into the estimation process of total carbon flux in the deep-time Earth system.

[0040] As some preferred examples of the present invention, the The value is approximately 1‰. ≈8‰.

[0041] Furthermore, , These two fractionation coefficients can be expressed as: ; ; in, The carbon isotope composition of carbonate rocks can be obtained by consulting existing data. V represents the fractionation that occurs during the precipitation of carbonate ions in seawater, and V≈1.3‰. Based on this, using the aforementioned δ 13 C CO2 The calculation formula can be obtained from the isotope fractionation coefficient. , δ is calculated from the value of V. 13 C CO2 The specific value of δ is then obtained. 13 C A The value of .

[0042] Similarly, using the δ mentioned above 13 C O The calculation formula can be obtained through and The value of δ is calculated. 13 C O The value is then used in Formula 2 in step S2.

[0043] Furthermore, it should be noted that δ in Formula 3 above... 13 C vm The value of can be obtained by consulting existing materials; therefore, it is a known value.

[0044] In addition, generally, δ 13 C carb The value and The values ​​are equal.

[0045] Thus, in Formula 3, except for F... vm Based on the values ​​of other parameters, F can be calculated using Formula 3. vm The specific value.

[0046] In the deep-time Earth system carbon flux estimation method described in this invention, the carbon content of surface systems such as the atmosphere, ocean, and organisms is considered in the Earth's carbon cycle system. The surface system is divided into three carbon pools: atmosphere, ocean, and organisms. By calculating the content of these three elements in the surface system and determining their carbon isotope composition, and taking into account the fractionation effect in the carbon cycle process of the surface system, the accurate estimation of deep-time Earth system carbon flux is achieved. This provides an accurate evaluation and determination method for deep-time Earth system carbon flux and carbon source analysis during carbon disturbance periods.

[0047] The deep-time Earth system carbon flux estimation method described in this invention has the following advantages and positive effects compared with previous deep-time Earth system carbon flux estimation techniques: First, it significantly improves the accuracy of carbon flux calculations during the carbon cycle: This invention divides the surface carbon pool into the marine carbon pool, the atmospheric carbon pool, and the biosphere carbon pool, and incorporates all three into the carbon cycle calculation, using formula M. S =M O +M A +M B Dynamic calculation of total carbon accurately reflects the real changes in the carbon pool during different geological periods. It focuses on the changing characteristics of the three elements in the deep time Earth system and can improve the accuracy of carbon flux calculation during the carbon cycle.

[0048] Second, traditional methods simply convert marine carbon isotopes (δ¹²) into δ¹² values. 13 C o The carbon isotopes of the Earth's surface system are equal to those of the surface system, and this invention uses formula M. S *δ 13 C S =M O *δ 13 C O +M A *δ 13 C A +M B *δ 13 C B This improvement quantifies isotopic differences in the ocean, atmosphere, and biosphere, eliminating estimation biases caused by neglecting carbon isotopic characteristics of the atmosphere and biosphere.

[0049] Third, traditional methods do not consider the fractionation effect during carbon input / output processes, leading to overestimation of carbon input and misjudgment of emission sources. This invention, however, explicitly incorporates the fractionation coefficient through Formula 3 and uses the formula to accurately calculate isotopic composition. In the carbon flux estimation process, it emphasizes the significant carbon isotopic fractionation effect during carbon injection into the Earth's surface system. Combined with the carbon isotopic composition characteristics of various carbon pools on Earth, it can effectively determine carbon emission sources and carbon fluxes in deep-time Earth system carbon disturbance events, significantly improving the accuracy of carbon cycle simulation.

[0050] Fourth, this invention is based on the law of conservation of mass, combined with the carbon emissions F from volcanic activity. vm Net weathering amount of carbonate rocks F carb and net emissions of organic carbon F org Based on the dynamic changes in carbon flux, Formula 3 is constructed. This carbon flux estimation model achieves high-resolution simulation of key processes in the deep carbon cycle, such as the eruption of large igneous provinces and ocean anoxic events, by quantifying the dynamic relationship between carbon flux and isotopic composition.

[0051] Fifth, the carbon content M in the atmospheric carbon pool A In the calculation process, M is calculated directly using the known atmospheric CO2 concentration. A Not only is the calculation process simple and easy to implement, but it also avoids the shortcomings of traditional methods that ignore atmospheric carbon content; The carbon content M in the marine carbon pool O In the calculation process, the mass m of the Phanerozoic seawater is taken into account. seawater The total dissolved inorganic carbon (DIC) content of the ocean is used to dynamically update the DIC value through the formula for calculating DIC, which can adapt well to the changes in the marine chemical environment in different geological periods. The carbon content M in the biosphere carbon pool B In the calculation process, a fixed value of 610 PgC is used based on the carbon storage of the modern biosphere, which is simple, accurate and easy to implement.

[0052] Sixth, compared with traditional methods, this invention significantly reduces the inaccuracy of estimation results through dynamic carbon pool segmentation and fractionation effect correction, providing more accurate data support for deep-time carbon cycle research. Simultaneously, by quantifying the contribution ratios of volcanic activity, carbonate weathering, and organic carbon cycling to carbon flux—for example, clarifying the dominant role of volcanic activity in carbon flux during the eruption of large igneous provinces, or the carbon-enhancing effect of organic carbon burial during ocean anoxic events—it helps to deepen the understanding of the carbon cycle driving mechanisms of dramatic climate changes in geological periods. The deep-time Earth system carbon flux estimation method described in this invention, by simulating carbon flux changes during periods of extreme carbon perturbation in the Phanerozoic Eon, can establish a "past-present-future" carbon cycle evolution framework, providing historical reference for assessing the degree of interference of current human activities on the carbon cycle, and helping to formulate more scientific carbon neutrality strategies.

[0053] In summary, the deep-time Earth system carbon flux estimation method provided by this invention systematically solves the four major defects of traditional techniques (fixed carbon pool assumption, neglect of atmospheric / biosphere carbon content, isotopic equivalence error, and failure to consider fractionation effect) through dynamic carbon pool segmentation, inclusion of multi-sphere isotopic composition, and correction for fractionation effect. Its high-precision and verifiable model framework not only enhances the scientific rigor of deep-time carbon cycle research but also provides a key tool for analyzing climate evolution mechanisms in geological history and predicting future climate change trends, demonstrating significant theoretical innovation and practical application value.

[0054] In addition, the present invention provides a deep-time Earth system carbon flux estimation system, which uses the above-mentioned deep-time Earth system carbon flux estimation method to estimate the deep-time Earth system carbon flux. Example

[0055] To verify the effectiveness of this invention in estimating carbon flux in the deep-time Earth system and analyzing carbon sources during periods of carbon disturbance, this design selected the Early Jurassic oceanic anoxic event as the research object. The carbon flux during this period was estimated using the aforementioned deep-time Earth system carbon flux estimation method, and possible carbon sources causing carbon disturbances during this period were speculated. The estimation results obtained are significantly different from those obtained using traditional methods; see details below. Figure 2 ,exist Figure 2 In the figure, the blue dashed box and the orange dashed box represent the results estimated by the conventional method and the method of the present invention, respectively: green represents the carbon emissions from organic carbon sources, thermogenic methane and natural gas hydrates as carbon sources, and red represents the carbon emissions from volcanic activity.

[0056] according to Figure 2 The results obtained using traditional methods (i.e., ignoring carbon isotope fractionation and equating the surface system with the ocean system) show negative carbon emissions in the explanation of the negative carbon isotope bias, indicating carbon fixation. This result is clearly inconsistent with reality, because a severe negative carbon isotope bias during carbon disturbance periods indicates the emission of light carbon, not fixation. In contrast, the results obtained by this invention are significantly more consistent with reality. Furthermore, the traditional method explains carbon emissions caused by volcanic activity as the cause of the negative carbon bias, which is also clearly inconsistent with reality. Volcanic emissions (carbon isotope values ​​of -4‰ to -6‰) are significantly higher than the carbon isotope values ​​of atmospheric carbon dioxide, and therefore could not cause a negative carbon isotope bias in the surface system. The estimation results obtained by this invention also prove that carbon emissions caused by volcanic activity cannot directly cause a severe negative carbon isotope bias.

[0057] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for estimating carbon flux in the deep-time Earth system, characterized in that, Including the following steps: S1, Segmentation of the Earth's Surface Carbon Pool: The Earth's surface carbon pool is segmented into the atmospheric carbon pool, the marine carbon pool, and the biosphere carbon pool, and M is used. S M A M O and M B These represent the carbon content of the surface system carbon pool, the atmospheric carbon pool, the marine carbon pool, and the biosphere carbon pool, respectively. Where M... S M A M O and M B The relationship between them satisfies Formula 1: M S =M O +M A +M B ; S2, incorporating carbon isotope composition: Incorporating carbon isotope composition into the carbon cycle of the Earth's surface system yields Formula 2: M S *δ 13 C S =M O *δ 13 C O +M A *δ 13 C A +M B *δ 13 C B , where δ 13 C S δ 13 C O δ 13 C A and δ 13 C B The carbon isotope composition of the Earth's surface system, ocean system, atmosphere, and biosphere, respectively. S3, Establishing a deep-time Earth system carbon flux estimation model: Based on the law of conservation of mass and combined with the isotopic fractionation effect during the carbon injection process into the Earth's surface system, formula three for estimating deep-time Earth system carbon flux is constructed: ； in, The total carbon flux of the deep-time Earth system; F vm F carb F org These are the carbon emissions from volcanic activity, net weathering of carbonate rocks, and net emissions of organic carbon, respectively. δ 13 C vm δ 13 C carb δ 13 C org These are the carbon isotope compositions of carbon emitted by volcanic activity, carbon isotope compositions of carbon from net weathering of carbonate rocks, and carbon isotope compositions of carbon from net organic emissions, respectively. , These are the isotopic fractionation coefficients of atmospheric carbon dioxide dissolved in water and carbonate rock deposition processes, respectively. S4, Calculate the total carbon flux of the deep-time Earth system. Determine the start and end times for estimating the total carbon flux of the deep-time Earth system. This yields the start and end times for estimating the total carbon flux of the deep-time Earth system. Then, calculate M at these two different times using Formula 2. S *δ 13 C S The value of this is used to obtain the total carbon flux of the deep-time Earth system. The value of , where, M at the termination time and the start time S *δ 13 C S Difference of values ​​divided by time interval; S5, calculate the carbon emissions F from volcanic activity according to Formula 3. vm The value is obtained from the total carbon flux of the deep Earth system. Carbon emissions F from volcanic activity in the deep Earth system vm Net weathering of carbonate rocks in deep Earth systems, F carb And the net emissions of organic carbon F in the deep Earth system org This constitutes a set of deep-time Earth system carbon flux estimates.

2. The method for estimating carbon flux in the deep-time Earth system according to claim 1, characterized in that, In Formula 3, the net weathering amount F of the carbonate rock carb = F wcarb - F bcarb , of which F bcarb F represents the amount of carbonate rock deposits. wcarb This represents the amount of carbonate rock dissolved.

3. The method for estimating carbon flux in the deep-time Earth system according to claim 1, characterized in that, In Formula 3, F org =F worg -F borg -F' borg , of which F worg F represents the amount of organic matter decomposed. borg For marine organic carbon deposition, F' borg This represents the amount of organic carbon deposited on land.

4. The method for estimating carbon flux in the deep-time Earth system according to claim 1, characterized in that, In Formulas 1 and 2, the carbon content M of the atmospheric carbon pool A =2.13* p CO2; in, p CO2 is the concentration of carbon dioxide in the atmosphere.

5. The method for estimating carbon flux in the deep-time Earth system according to claim 1, characterized in that, The carbon content M of the marine carbon pool O The calculation method is as follows: M O =12*m seawater *DIC; Where, m seawater The mass of seawater in the Phanerozoic Eon; DIC stands for Total Dissolved Inorganic Carbon in the ocean.

6. The method for estimating carbon flux in the deep-time Earth system according to claim 5, characterized in that, The total dissolved inorganic carbon (DIC) content in the ocean is calculated as follows: ； [CO2] represents the carbon dioxide content in seawater; K1 * K2 * It is the chemical reaction equilibrium constant; H + This represents the concentration of hydrogen ions in seawater.

7. The method for estimating carbon flux in the deep-time Earth system according to claim 6, characterized in that, The carbon dioxide content [CO2] in seawater is calculated as follows: [CO2]=K o * p CO2; Among them, K o is the Henry's constant.

8. The method for estimating carbon flux in the deep-time Earth system according to claim 1, characterized in that, In Formulas 1 and 2 above, the carbon content M of the biosphere carbon pool is... B The calculation method is as follows: M B =610PgC, where 610 is the carbon storage value of the biosphere carbon pool and PgC is the unit of measurement.

9. The method for estimating carbon flux in the deep-time Earth system according to claim 1, characterized in that, In the second formula, the δ 13 C B The value of δ 13 C org The values ​​of δ are equal, 13 C A The value of δ 13 C CO2 The values ​​of δ are equal. 13 C CO2 and δ 13 C O The calculation method is as follows: ； ； in, This represents the carbon isotopic composition of carbonate rocks, where V represents the fractionation that occurs during the precipitation of carbonate ions in seawater.

10. A deep-time Earth system carbon flux estimation system, characterized in that, It uses the estimation method described in any one of claims 1 to 9 to estimate the carbon flux of the deep-time Earth system.

Images