CN103529487B - The method of discrimination of a kind of curtain source carbon dioxide infilling time - Google Patents

Abstract

The present invention proposes a kind of curtain source CO ₂the method of discrimination of infilling time, belongs to oil and gas geology field.The present invention, by setting up the diagenesis paragenetic sequence of sandstones with dawsonite, differentiates the origin cause of formation of dawsonite, determines curtain source CO ₂with the sequential relationship of hydrocarbon charge, judge the oil charging time in dissimilar sandstones with dawsonite, finally carry out curtain source CO ₂the differentiation of infilling time, obtains curtain source CO ₂infilling time.The present invention judges curtain source CO by dawsonite ₂infilling time, for there being curtain source CO in the volcanicity of many phases and fluid-filled petroliferous basin ₂the judgement of infilling time provides effectively, method accurately.<!-- 2 -->

Description

The method of discrimination of a kind of curtain source carbon dioxide infilling time

Technical field

The invention belongs to oil and gas geology field, be specifically related to a kind of curtain source CO ₂the method of discrimination of infilling time.

Background technology

Curtain source CO in sedimentary basin ₂infilling time be carry out CO ₂-sandstone interacts and CO ₂the basis of-crude oil repercussion study.Most CO in the world ₂the formation in gas (Tibetan) field is relevant with magmation, and, CO ₂gas (Tibetan) field and have the volcanics of genetic relationship mostly spatially contiguous or have transfer passages and link up with it, the former is as developed or discarded CO 9 on Colorade USA plateau ₂gas field (non-patent literature 1), Bohai gulf basin spend 17, positive 25 gas reservoirs and Gaoqing gas field (non-patent literature 2), square atmosphere of being king of the latter as Bohai gulf basin is hidden and Pingnan County's gas reservoir (non-patent literature 3).The inorganic CO of commercial value that what Eastern China found at present have ₂gas field all belongs to the volcanic-mantle origin cause of formation (non-patent literature 4), as Song-liao basin south ten thousand quintar CO ₂gas reservoir, northern prosperous moral eastern gas reservoir, Jiyang Depression, The Bohaiwan Basin square king CO ₂huang Qiao CO of gas reservoir, Subei Basin ₂gas reservoir and three piece of water CO ₂gas reservoir etc.These volcanic-mantles CO ₂distribution and 9 north west basaltic magma mobile belt spread in Neogene period to Quaternary period consistent (non-patent literature 5) of gas reservoir (seedling), as Jiyang depression CO ₂gas reservoir is mainly distributed in Yangxin area that Cenozoic volcanic rocks grows and Gaoqing, Pingnan County, flower ditch one band; HUANGHUA DEPRESSION CO ₂gas accumulations distribution grow in Cenozoic basalt Zhai village, friendly village, big-and-middle prosperous and neat housework area (non-patent literature 6); Song-liao basin ten thousand Jinta area 10,000 well bores and meets cumulative thickness is the volcanics of 937m; Wuerxun Sag in Hailaer Basin CO ₂copper 1 well near gas reservoir bores meets geochemistry of Yanshanian granitoids, the high yield CO such as Soviet Union 8, Soviet Union 3, Soviet Union 16 ₂well also bore and meet the volcanics such as trachyte and eruptive tuff; And inorganic CO ₂(non-patent literature 7) on crater is just located in the Tian Chi Lake of Mountain Baitou that gas seepage is grown and Wudalianchi.Above statement of facts volcanics and inorganic CO ₂the distribution relation of gas reservoir (seedling) is close, is curtain source CO ₂the gas source rock of gas reservoir.

Based on this understanding, some researchers will with CO ₂the eruption age of the volcanics of genetic relationship is had to be considered as CO ₂the infilling time of gas reservoir, such as, the Bravo fornix CO on Colorade USA plateau ₂the infilling time in gas field is (10 ~ 8ka), McElmo fornix CO ₂the infilling time in gas field is 70 ~ 42Ma (non-patent literature 1); Australia Otway basin LadbrokeGrove natural-gas field (CO ₂content is 26 ~ 57mol%) infilling time be 1Ma ~ 4500a (non-patent literature 8).The method is current CO ₂the main method of discrimination of gas reservoir infilling time.

Said method is easy-to-understand, and application is simple, is the method that Chinese scholars generally adopts.But when basin and periphery have the volcanicity of many phases and be fluid-filled, simply quote the volcanic eruption age and really can not determine curtain source CO ₂infilling time, as Song-liao basin south middle-shallow layer once there are two phase hydrocarbon charge events, its infilling time is respectively 85 ~ 65Ma and 50 ~ 25Ma(non-patent literature 9); Inner and the surrounding area of Song-liao basin there occurs respectively with Upper Cretaceous Datun Huoshanqun (92.3Ma), Paleogene Period Shuangliao volcanic cluster (51.0 ~ 41.6Ma) (non-patent literature 10) and three phases volcanicity that the Quaternary period, Wudalianchi Huoshanqun (0.56 ~ 0.27Ma, 1719-1721a and 1721a) (non-patent literature 11) was representative.Therefore, must look for another way, find one and indirectly, effectively determine curtain source CO ₂the approach of infilling time.

Summary of the invention

Problem to be solved by this invention, when there is too much phase hydrocarbon charge event in stratum, how effectively to determine curtain source CO ₂infilling time.

The present invention is by CO ₂" tracing mineral "-dawsonite solve this difficult problem, emphasis has found out the CO of dawsonite record ₂the origin cause of formation and infilling time.

Concrete steps of the present invention comprise:

1, the diagenesis paragenetic sequence of sandstones with dawsonite is set up: the analysis test method such as X-ray diffraction analysis, JSM-6700 type scanning electron microscope, CL8200MK3 & 4 type optics cathodeluminescence platform, image analysis software adopting ﹤ 2 μm of parts in the dyeing of polarizing microscope, carbonate mineral, sandstone, determine classification and the content of sandstone skeleton composition, determine type and the content of cementing matter and authigenic mineral, determine the mutual relationship between diagenesis types, identify CO ₂fill front and CO ₂diagenesis paragenetic association after filling, and then set up the diagenesis paragenetic sequence of sandstones with dawsonite.

2, the origin cause of formation of dawsonite differentiates: utilize polarizing microscope or scanning electron microscope to find out the mineral with dawsonite symbiosis, then oxygen and carbon isotopes analysis is carried out to dawsonite, described oxygen and carbon isotopes analysis adopts Within Monominerals mass spectrometry or laser microprobe mass spectrometer analytic approach, by kalzit-CO ₂fractionation factor as being equivalent to synthermal lower dawsonite-CO ₂fractionation factor calculate the CO balanced with dawsonite ₂after the carbon isotope value of gas, utilize organic or inorganic CO ₂differentiate plate (see Fig. 1) method, differentiate the CO balanced with dawsonite ₂the origin cause of formation of gas, the i.e. origin cause of formation of dawsonite.

3, curtain source CO is determined ₂with the sequential relationship of hydrocarbon charge: judge that dawsonite is as inorganic, the CO namely balanced with dawsonite ₂gas is curtain source CO ₂afterwards, with oil-containing CO ₂in gas reservoir and oil reservoir, sandstones with dawsonite is research object, with polarizing microscope and fluorescent microscope for Main Means, carries out following observation and analysis: (1) utilizes polarizing microscope, with spike CO ₂the dawsonite filled is mark, in diagenesis paragenetic sequence, identify CO ₂fill front and CO ₂diagenesis paragenetic association after filling; (2) polarizing microscope, fluorescent microscope is utilized, at CO ₂fill front and CO ₂fill in the authigenic mineral formed afterwards and look for oil and gas inclusion, intergranular oil stain and pitch in healing crack; (3) on the basis of above-mentioned observation, comprehensively CO is determined ₂with the precedence of oil charging, if namely at CO ₂find oil gas inclusion, intergranular oil stain and pitch in the authigenic mineral formed before filling and in healing crack, hydrocarbon charge formerly; Vice versa.

The differentiation of the oil charging time 4, in dissimilar sandstones with dawsonite: (1) oil-containing CO ₂gas reservoir sandstones with dawsonite PetroChina Company Limited. infilling time, first, utilizes cold and hot of THMS600 and TS1500 type to measure oil-containing CO ₂the homogenization temperature of saline inclusion in gas reservoir (with oil gas inclusion symbiosis); Then, according to the phase time of peak value homogenization temperature determination hydrocarbon charge; Finally, the infilling time of time oil of each phase is determined in conjunction with buried history and thermal evolution history curve.(2) the oil charging time in oil reservoir sandstones with dawsonite, according to the authigenic illite K/Ar age determination data in oil reservoir, the infilling time of oil is determined.

5, curtain source CO ₂the differentiation of infilling time: according to the position of dawsonite in diagenesis paragenetic sequence, in conjunction with the oil charging time in this diagenesis paragenetic sequence, can determine curtain source CO ₂the range of age filled.(1) CO during first phase hydrocarbon charge ₂the differentiation of infilling time: first, according to the authigenic illite K/Ar age determination data in oil reservoir, determines the infilling time of oil; Then, curtain source CO is determined ₂with the sequential relationship of hydrocarbon charge, constraint curtain source CO ₂upper and lower limit time (the curtain source CO filled ₂fill and be later than hydrocarbon charge, this age data is the lower limit time; Otherwise be upper limit time); Finally, in conjunction with appearing and drilling well age of volcanic rock data, curtain source CO is determined ₂the appropriate age filled.(2) CO during hydrocarbon charge of many phases ₂the differentiation of infilling time: first utilize fluid inclusions homogenization temperature, determines the phase time of hydrocarbon charge; Then, according to the position of dawsonite in diagenesis paragenetic sequence, determine curtain source CO ₂with the sequential relationship of hydrocarbon charge; Finally, curtain source CO is determined according to the oil charging time ₂the range of age filled.(3) with the quasi-instantaneous CO of hydrocarbon charge ₂the differentiation of infilling time: according to paragenetic sequence and Fluid-inclusion analysis, if confirm curtain source CO ₂infilling time and the quasi-instantaneous words of certain phase hydrocarbon charge, utilize illite K/Ar to determine year or fluid inclusions homogenization temperature is comprehensively analyzed this phase oil charging time that (in conjunction with buried history and thermal history) draw and is curtain source CO ₂infilling time.

Within Monominerals mass spectrometry in described oxygen and carbon isotopes analysis is: for the sample that dawsonite content is high, adopts physical separation method to obtain dawsonite Within Monominerals and carries out oxygen and carbon isotopes analysis.The feature lower than silicate mineral and other carbonate minerals according to dawsonite proportion, first pulverizes sandstones with dawsonite, slightly grinds; Then, utilize heavy-fluid isolation technics to obtain dawsonite Within Monominerals, finally, utilize the purity of X-ray diffraction analytical control dawsonite.

Laser microprobe mass spectrometer analytic approach in described oxygen and carbon isotopes analysis is: " laser microprobe mass spectrometer analytic approach " for the sample that dawsonite content is lower, will be adopted to measure.Under the microscope, utilize laser beam heats object carbonate mineral, make it decomposite CO ₂gas.By the CO obtained ₂gas send mass spectrometer (MAT251/MAT252 etc.) micro-sampling system to test its oxygen and carbon isotopes after vacuum refrigeration purifying.Its great advantage is, has higher spatial resolution.

Described dawsonite-CO ₂fractionation factor calculate be adopt following equation calculate:

$1000\ln =\frac{1000+\mathrm{\&delta;}\left(\mathrm{calcits}\right)}{1000+\mathrm{\&delta;}\left(C{O}_2\right)}=-(8.914\&times;{10}^8)T^{-9}+(8.557\&times;{10}^6)T^{-2}+-(18.11\&times;{10}^3)T^{-1}+8.27\frac{1000+\mathrm{\&delta;}\left(\mathrm{dawsonits}\right)}{1000+\mathrm{\&delta;}\left({\mathrm{CO}}_2\right)}=\frac{1000+\mathrm{\&delta;}\left(\mathrm{calcits}\right)}{1000+\mathrm{\&delta;}\left({\mathrm{CO}}_2\right)}$

Mineral of the present invention determine the more conventional source rock Ding Nianfa of year method following advantage:

(1) method application of the present invention is wider.Curtain source CO ₂source rock Ding Nianfa is applicable to CO ₂only there is first phase volcanicity gas reservoir development area, or has volcano of many phases movable but the restriction of the migration pathway such as can to rupture, and judges which phase volcanicity and CO ₂gas reservoir be formed with direct relation.And curtain source CO ₂mineral Ding Nianfa has broken away from above-mentioned restriction, for there being curtain source CO in the volcanicity of many phases and fluid-filled petroliferous basin ₂the judgement of infilling time provides effective ways.

(2) method precision of the present invention is higher.Curtain source CO ₂source rock Ding Nianfa be with CO ₂gas reservoir has the age of volcanic rock of genetic relationship to be its infilling time, these age of volcanic rock data and curtain source CO ₂infilling time can completely the same (the rapid pool-formation same period), also may differ comparatively large (later stage repeatedly becomes to hide).And curtain source CO ₂mineral Ding Nianfa is by curtain source CO ₂with the sequential relationship of hydrocarbon charge, differentiate curtain source CO by the oil charging time ₂infilling time, error is little, precision is high.

Accompanying drawing illustrates:

Fig. 1: organic or inorganic CO ₂differentiate plate

Fig. 2: Song-liao basin south forms the CO of dawsonite ₂the origin cause of formation differentiates figure

Embodiment:

The experimental technique used in embodiment below if no special instructions, is conventional method.

Below by curtain source CO ₂should the be used for further instruction of mineral Ding Nianfa in Song-liao basin south of infilling time.

1, the diagenesis paragenetic sequence of sandstones with dawsonite is determined

In Song-liao basin south, dawsonite authigenic mineral is mainly distributed in the spring head group four sections of magnificent word well terrace and Fuxin uplift, the Qingshankou group-Yao Jia group on the terrace, Qingshankou group three Duan Hehong hilllock of Changling Sag and Nenjiang group three sections of sandstone.The rock type of sandstones with dawsonite is mainly arkosic arenite, feldspar rock-fragment sandstone and landwaste arkosic arenite.Polarizing microscope and scanning electron microscopic observation show, CO ₂fill after formed authigenic mineral combination be mainly dawsonite, ferrodolomite and late period kalzit.Except with except authigenic mineral form output, at Fuxin uplift, dawsonite is also distributed in sandstone crack.In crack, dawsonite is half filling shape, and local, crack sees there is oil-impregnation phenomenon.

2, the origin cause of formation of dawsonite differentiates

Utilize polarizing microscope or scanning electron microscope to find out the mineral with dawsonite symbiosis, then oxygen and carbon isotopes analysis is carried out to dawsonite, find the δ of dawsonite in magnificent word well terrace, Changling Sag and Hong Gang terrace sandstone ¹³c distribution range is-5.30 ‰ ~ 3.29 ‰ (PDB), and wherein the Data distribution8 of 82.8% is interval in-2 ‰ ~ 2 ‰ (PDB); δ ¹⁸the distribution range of O is wider, is 8.95 ‰ ~ 21.04 ‰ (SMOW).Generally, δ wide with sample distribution ¹³c Data distribution8 is concentrated as feature.According to dawsonite-CO ₂fractionation factor accounting equation show and the δ that dawsonite balances ¹³c _cO2scope be-11.7 ‰ ~-4.2 ‰.Further analysis finds, the CO of Song-liao basin ₂based on inorganic, its δ ¹³c _cO2between-2 ‰ ~-10 ‰, mean value is about-5 ‰, is the volcanic-mantle origin cause of formation.According to this standard, the dawsonite main (89.6%) in Song-liao basin south is formed at inorganic CO ₂background, a small amount of (10.4%) is formed at organic C O ₂background (see Fig. 2).The CO that Song-liao basin south causes dawsonite to be formed is described ₂with the CO in gas reservoir ₂there is identical carbon source, be the volcanic-mantle origin cause of formation.

3, curtain source CO is determined ₂with the sequential relationship of hydrocarbon charge

(1) differentiation of Oil and gas charging period

According to the Hydrocarbon Property in the oil gas inclusion of Song-liao basin south, in conjunction with its host minerals or occurrence, the hydrocarbon charge in sandstones with dawsonite was obviously divided into for two phases.

First phase inclusion is mainly liquid hydrocarbon inclusion, is gas-liquid hydrocarbon inclusion on a small quantity.Inclusion compose be stored in early stage quartz overgrowth limit, early stage kalzit and cut and do not cut wear quartz overgrowth limit crack in.In early days in quartz overgrowth limit, inclusion is fragmentary or one-tenth band distribution inside secondary enlargement limit, growth abundance differs greatly, low abundance (GOI<0.5%), median abundance (GOI is about 1% ~ 3%) and high abundance (GOI is about 10%) person all have output, being mainly liquid hydrocarbon inclusion, is gas-liquid hydrocarbon inclusion on a small quantity.Compose the inclusion be stored in early stage kalzit to distribute in groups, be brown, auburn liquid hydrocarbon inclusion.Cutting and do not cutting in the crack of wearing quartz overgrowth limit, inclusion is zonal arrangement, is mainly liquid hydrocarbon inclusion, is gas-liquid hydrocarbon inclusion individually.With the homogenization temperature peak value different regions slightly difference of the saline inclusion of first phase oil gas inclusion symbiosis, wherein, Hong Gang terrace is 70 ~ 90 DEG C, and Qianan depression is 70 ~ 80 DEG C, and magnificent word well terrace is 70 ~ 100 DEG C.

Second phase inclusion is mainly gas-liquid hydrocarbon inclusion (accounting for 60% ~ 90%), is secondly liquid hydrocarbon inclusion (accounting for 40% ~ 9%), is extremely individually gas hydrocarbon inclusion (accounting for about 1%).Inclusion compose be stored in kalzit in late period, quartz overgrowth in late period limit, dawsonite and wear cut clastic quitz and secondary enlargement limit thereof microfissure in and in chip feldspar.Compose and be stored in inclusion in quartz overgrowth in late period limit and grow abundance medium (GOI is about 3%), inclusion in groups, become band distribution.Compose be stored in late period kalzit and dawsonite in inclusion in groups or the distribution of isolated shape, wherein, the inclusion in late period kalzit grows abundance high (late period of about 70% ~ 80% sees there is inclusion in kalzit).Wearing in the microfissure cutting clastic quitz and secondary enlargement limit thereof, inclusion is zonal arrangement.In detrital feldspar, inclusion also in groups, become band distribution.The homogenization temperature peak value of the saline inclusion of Hong Gang terrace and second phase oil gas inclusion symbiosis is 100 ~ 120 DEG C, and Qianan depression is 90 ~ 100 DEG C, and magnificent word well terrace is 110 ~ 120 DEG C.

(2) curtain source CO ₂with the sequential relationship of hydrocarbon charge

The diagenesis paragenetic sequence of sandstones with dawsonite and Study of fluid inclusions show, Song-liao basin south once there occurs the fluid-filled process of three phase resources in middle-shallow layer stratum.The first phase fills based on liquid hydrocarbon, and the second phase fills based on gas-liquid hydrocarbon, and the third phase is curtain source CO ₂fill.Curtain source CO ₂fill slightly be later than second phase hydrocarbon charge or with its roughly simultaneously, material evidence is:

1. first phase oil gas inclusion (based on liquid hydrocarbon inclusion) is grown in the inner side on quartz overgrowth limit, and second phase oil gas inclusion (based on gas hydrocarbon inclusion) is grown in outside, and spike CO ₂the dawsonite filled generally is filled in the pore space of quartz overgrowth limit remaining after crystallization, and CO is described ₂fill slightly be later than second phase hydrocarbon charge.

2. compose in dawsonite and deposit second phase oil gas inclusion (gas liquid inclusion), imply that pore fluid is with CO when dawsonite crystallization ₂and the component being dissolved in local water is main, oil gas is auxiliary.

3. not only gas phase CO is detected wearing in the inclusion cut in clastic quitz and secondary enlargement limit microfissure thereof ₂, liquid phase CO ₂and CO ₃ ^2-, and CH detected ₄component, illustrates CO ₂in migration process, once there occurs the extraction to hydro carbons, although can not get rid of the possibility of the hydro carbons of extraction early origin, the possibility of the hydro carbons that extraction and its standard fill simultaneously is larger.

4, the differentiation of oil charging time

Zou Caineng etc. (non-patent literature 9) determine year for the illite K/Ar that Fuxin uplift Fuyu Reservoirs is carried out and fluid inclusions homogenization temperature is comprehensively analyzed the two phase oil gas injection lengths that (in conjunction with buried history and thermal history) draw and is followed successively by 85 ~ 65Ma and 50 ~ 25Ma, the former is equivalent to Nenjiang-open fire phase, and the latter's main body is Paleogene Period.

5, curtain source CO ₂the differentiation of infilling time

By finding the research in crack, Song-liao basin south, in macroscopic fracture, both seeing there are drusy dawsonite stuff, seen again have oil-containing phenomenon, having illustrated that crack and microfissure were all formed at CO ₂before second phase hydrocarbon charge.Although for Song-liao basin south first phase oil gas injection length be Nenjiang phase-still there are different understanding or statement in Nenjiang end of term open fire phase, but second phase hydrocarbon charge betides Cretaceous period end (the open fire end of term)-Paleogene Period and but obtains general approval.In view of second phase hydrocarbon charge and curtain source CO ₂filled accurate simultaneously, therefore, curtain source CO ₂fill also should betide Cretaceous period end (the open fire end of term)) Paleogene Period.

List of references

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[3] Hu Anping, wears Venus, Yang Chun, Zhou Qinghua, Ni Yunyan. Bohai gulf basin C0 ₂gas field (Tibetan) Geochemical Characteristics and distribution. Petroleum finance, 2009,36(2): 181-189.

[4] Zhang Shuichang, Zhu Guangyou. the distribution of Sedimentary Basins of China medium gas fields and Natural Gas Origin. Chinese science D collects: geoscience .2007,37 (supplementary issue II): 1-11.

[5] Venus is worn, Hu Guoyi, Ni Yunyan etc. Eastern China Distribution of Natural feature. rock gas geoscience .2009,20 (4): 471-487.

[6] Wang Xingmou, Xia Bin, Chen Genwen etc. East China Cenozoic magmation is to regional CO ₂the restriction of formation time. macrotectonics and metallogeny, 2004a, 28 (3): 338-344.

[7] Qu Xiyu, Liu Li, high jade is skilful. Northeast Area of China volcanic-mantle CO ₂compose the geologic record of depositing. petroleum journal .2010,31 (1): 74-80.

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Claims (4)

1. a curtain source CO ₂the method of discrimination of infilling time, is characterized in that the method comprises the following steps:

A. the diagenesis paragenetic sequence of sandstones with dawsonite is set up: adopt the X-ray diffraction analysis of ﹤ 2 μm of parts in the dyeing of polarizing microscope, carbonate mineral, sandstone, JSM-6700 type scanning electron microscope, CL8200MK3 & 4 type optics cathodeluminescence platform or image analysis software analysis test method, determine type and the content of sandstone skeleton clastic constituents, determine type and the content of cementing matter and authigenic mineral, determine the mutual relationship between diagenesis types, identify CO ₂fill front and CO ₂diagenesis paragenetic association after filling, and then set up the diagenesis paragenetic sequence of sandstones with dawsonite;

B. the origin cause of formation of dawsonite differentiates: utilize polarizing microscope or scanning electron microscope to find out the mineral with dawsonite symbiosis, then oxygen and carbon isotopes analysis is carried out to dawsonite, described oxygen and carbon isotopes analysis adopts Within Monominerals mass spectrometry or laser microprobe mass spectrometer analytic approach, by kalzit-CO ₂fractionation factor be considered as being equivalent to synthermal lower dawsonite-CO ₂fractionation factor calculate the CO balanced with dawsonite ₂after the carbon isotope value of gas, utilize organic or inorganic CO ₂differentiate plate method, differentiate the CO balanced with dawsonite ₂the origin cause of formation of gas, the i.e. origin cause of formation of dawsonite.

C. curtain source CO is determined ₂with the sequential relationship of hydrocarbon charge: with oil-containing CO ₂in gas reservoir and oil reservoir, sandstones with dawsonite is research object, with polarizing microscope and fluorescent microscope for Main Means, carries out following observation and analysis: (1) utilizes polarizing microscope, with spike CO ₂the dawsonite filled is mark, in diagenesis paragenetic sequence, identify CO ₂fill front and CO ₂diagenesis paragenetic association after filling; (2) polarizing microscope, fluorescent microscope is utilized, at CO ₂fill front and CO ₂fill in the authigenic mineral formed afterwards and look for oil and gas inclusion, intergranular oil stain and pitch in healing crack; (3) on the basis of above-mentioned observation, comprehensively CO is determined ₂with the precedence of oil charging, if namely at CO ₂find oil gas inclusion, intergranular oil stain and pitch in the authigenic mineral formed before filling and in healing crack, hydrocarbon charge formerly; Vice versa;

The differentiation of the oil charging time d. in dissimilar sandstones with dawsonite: (1) is for oil-containing CO ₂gas reservoir sandstones with dawsonite PetroChina Company Limited. infilling time, first, utilizes cold and hot of THMS600 and TS1500 type to measure oil-containing CO ₂the homogenization temperature of the saline inclusion in gas reservoir, described saline inclusion is with oil gas inclusion symbiosis; Then, according to the phase time of peak value homogenization temperature determination hydrocarbon charge; Finally, the infilling time of time oil of each phase is determined in conjunction with buried history and thermal evolution history curve; (2) the oil charging time in oil reservoir sandstones with dawsonite, according to the authigenic illite K/Ar age determination data in oil reservoir, the infilling time of oil is determined;

E. curtain source CO ₂the differentiation of infilling time: according to the position of dawsonite in diagenesis paragenetic sequence, in conjunction with the oil charging time in this diagenesis paragenetic sequence, determines curtain source CO ₂the range of age filled: CO during (1) first phase hydrocarbon charge ₂the differentiation of infilling time: first, according to the authigenic illite K/Ar age determination data in oil reservoir, determines the infilling time of oil; Then, curtain source CO is determined ₂with the sequential relationship of hydrocarbon charge, constraint curtain source CO ₂the upper and lower limit time filled, curtain source CO ₂fill and be later than hydrocarbon charge, this age data is the lower limit time; Otherwise be upper limit time; Finally, in conjunction with appearing and drilling well age of volcanic rock data, curtain source CO is determined ₂the appropriate age filled.(2) CO during hydrocarbon charge of many phases ₂the differentiation of infilling time: first utilize fluid inclusions homogenization temperature, determines the phase time of hydrocarbon charge; Then, according to the position of dawsonite in diagenesis paragenetic sequence, determine curtain source CO ₂with the sequential relationship of hydrocarbon charge; Finally, curtain source CO is determined according to the oil charging time ₂the range of age filled.(3) with the quasi-instantaneous CO of hydrocarbon charge ₂the differentiation of infilling time: according to paragenetic sequence and Fluid-inclusion analysis, if confirm curtain source CO ₂infilling time and the quasi-instantaneous words of certain phase hydrocarbon charge, utilize illite K/Ar to determine year or fluid inclusions homogenization temperature is comprehensively analyzed, and in conjunction with buried history and thermal history, this phase oil charging time drawn is curtain source CO ₂infilling time.

2. a kind of curtain source CO as claimed in claim 1 ₂the method of discrimination of infilling time, the Within Monominerals mass spectrometry in described oxygen and carbon isotopes analysis is for the high sample of dawsonite content, first, sandstones with dawsonite is pulverized, is slightly ground; Then, utilize heavy-fluid isolation technics to obtain dawsonite Within Monominerals, finally, utilize the purity of X-ray diffraction analytical control dawsonite.

3. a kind of curtain source CO as claimed in claim 1 ₂the method of discrimination of infilling time, the laser microprobe mass spectrometer analytic approach in described oxygen and carbon isotopes analysis is: for the sample that dawsonite content is lower, under the microscope, utilizes laser beam heats object carbonate mineral, makes it decomposite CO ₂gas, by the CO obtained ₂gas send the micro-sampling system of mass spectrometer to test its oxygen and carbon isotopes after vacuum refrigeration purifying.

4. a kind of curtain source CO as claimed in claim 1 ₂the method of discrimination of infilling time, described dawsonite-CO ₂fractionation factor calculate adopt equation

$1000\ln \frac{1000+\mathrm{\&delta;}\left(calcite\right)}{1000+\mathrm{\&delta;}\left({\mathrm{CO}}_2\right)}=-(8.914\&times;{10}^3)T^{-9}+(8.557\&times;{10}^6)T^{-2}+-(18.11\&times;{10}^3)T^{-1}+8.27\frac{1000+\mathrm{\&delta;}\left(dawsonite\right)}{100+\mathrm{\&delta;}\left({\mathrm{CO}}_2\right)}=\frac{1000+\mathrm{\&delta;}\left(calcite\right)}{1000+\mathrm{\&delta;}\left({\mathrm{CO}}_2\right)}.$

Calculate.