1997 Vol. 15, No. 2
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Display Method:
1997, 15(2): 14-18.
Abstract:
There are some differences in sedimentary environments of continental and marine source rocks, thesedimentary model of organic-carbon-rich mudstones was investigated based on the data of marine sourcerocks at hove and abroad. The research result of paleo-oceanography,stratigraphic sequences and oxygenisotopes of plankton Foraminifera indicated that the organic-carbonich sediments in the north Pacificcoust are of similarity in age and paleodimate, according to the data of stratigraphic sequences andgeochemstry,the distribution and cotrolling factor of organic matter were discussed as well.
There are some differences in sedimentary environments of continental and marine source rocks, thesedimentary model of organic-carbon-rich mudstones was investigated based on the data of marine sourcerocks at hove and abroad. The research result of paleo-oceanography,stratigraphic sequences and oxygenisotopes of plankton Foraminifera indicated that the organic-carbonich sediments in the north Pacificcoust are of similarity in age and paleodimate, according to the data of stratigraphic sequences andgeochemstry,the distribution and cotrolling factor of organic matter were discussed as well.
1997, 15(2): 31-34.
Abstract:
he secondary ions of the hydrocarbon fragments suchas CH, CH3 and benzene series homologues,etc. can be detected by ion microprobe(SIM S) in the organic analysis of carbonate rocks. There is a close relationship of the peak and its abundance of these fragment ions with the themical com posi do nand molecular structure of the organic materials detected. There is certain regularity with the change ofCH/C and CH3 /C ratios which could reach the maximum at theoil forming period. And the value of themethyl ratio between arene compounds and benzene serial homologues can reflect the cha ng a of o rganicmatuity and shown good linear relationship vitrinite reflectance(R).This paper represented part of theexperimental results obtained during the study of the oil and soure rock correlation and oil-gas evolutionof marine carbonate rocks in the Yunnan, Guizhou and Guangxi area by using SIM S.
he secondary ions of the hydrocarbon fragments suchas CH, CH3 and benzene series homologues,etc. can be detected by ion microprobe(SIM S) in the organic analysis of carbonate rocks. There is a close relationship of the peak and its abundance of these fragment ions with the themical com posi do nand molecular structure of the organic materials detected. There is certain regularity with the change ofCH/C and CH3 /C ratios which could reach the maximum at theoil forming period. And the value of themethyl ratio between arene compounds and benzene serial homologues can reflect the cha ng a of o rganicmatuity and shown good linear relationship vitrinite reflectance(R).This paper represented part of theexperimental results obtained during the study of the oil and soure rock correlation and oil-gas evolutionof marine carbonate rocks in the Yunnan, Guizhou and Guangxi area by using SIM S.
1997, 15(2): 40-44.
Abstract:
According to the theory of petroleum system,it was not only to form the concept of the gas-geneticsystem first, but also to classify the gas-bearing system,gas-bearing association and gas-genetic systemin the Tarim basin .Moreover the characterization of the gas-bearing system in the Tarim basin was in-vestigated. All of these are important to the exploration of natural gases in the Tarim basin.
According to the theory of petroleum system,it was not only to form the concept of the gas-geneticsystem first, but also to classify the gas-bearing system,gas-bearing association and gas-genetic systemin the Tarim basin .Moreover the characterization of the gas-bearing system in the Tarim basin was in-vestigated. All of these are important to the exploration of natural gases in the Tarim basin.
1997, 15(2): 54-57.
Abstract:
The Fanzhi brown coal (R°% 0. 28) was subjected to hydrous pyrolysis. The brown coal and solidpyrolyer residues (R°% 0.32y-0.68) were studied by 13 Cnmr. The Shulan(R°% 0.32) and Huangxianbrown coal(R°% 0. 68) were also analyzed by 13C nmr. The results indicated that progressive changesin the chemistry of early coal evolution are likely.(1) demethylation of guaiacyl units to form catechollike structures that are dominant components of the brown coal,(2) cleavage of aryl ether linkages toform phenols and reactive carbocations that alkylate the catechol rings and(3) dehydration of the cate-chol-like structuens to form alkyl phenols. Aromatic ring substitution index(σ)was nearly constant inthe early evolution. The results suggested that aromatic ring in ligin structure did not fuse to form pol-yaromatic rings beforeR°% 0. 7 and CH4was one of the main products in the early coalification process.
The Fanzhi brown coal (R°% 0. 28) was subjected to hydrous pyrolysis. The brown coal and solidpyrolyer residues (R°% 0.32y-0.68) were studied by 13 Cnmr. The Shulan(R°% 0.32) and Huangxianbrown coal(R°% 0. 68) were also analyzed by 13C nmr. The results indicated that progressive changesin the chemistry of early coal evolution are likely.(1) demethylation of guaiacyl units to form catechollike structures that are dominant components of the brown coal,(2) cleavage of aryl ether linkages toform phenols and reactive carbocations that alkylate the catechol rings and(3) dehydration of the cate-chol-like structuens to form alkyl phenols. Aromatic ring substitution index(σ)was nearly constant inthe early evolution. The results suggested that aromatic ring in ligin structure did not fuse to form pol-yaromatic rings beforeR°% 0. 7 and CH4was one of the main products in the early coalification process.
1997, 15(2): 66-69.
Abstract:
The geochemical parameters of the natural gas migration were disccussed in the paper basedgemical study of natural gasesin the Dongfang 1-1 gasfield, Yinggai Basin, South China Sea.showed that low molecular n-alkane,ratio of isoalkanes to n-alkane,ratio of aramatics ratio of isoalkanes to n-lkanes ratio of aramatics to n-alkcnes,δ13value of alkanes and nonhydrocarbon gas content, could be used as geochemical parameters of thegas migration. The vertical variations of these parameters indicated the vertical migration featureralgases in the Dongfang 1一1 gasfield
The geochemical parameters of the natural gas migration were disccussed in the paper basedgemical study of natural gasesin the Dongfang 1-1 gasfield, Yinggai Basin, South China Sea.showed that low molecular n-alkane,ratio of isoalkanes to n-alkane,ratio of aramatics ratio of isoalkanes to n-lkanes ratio of aramatics to n-alkcnes,δ13value of alkanes and nonhydrocarbon gas content, could be used as geochemical parameters of thegas migration. The vertical variations of these parameters indicated the vertical migration featureralgases in the Dongfang 1一1 gasfield
1997, 15(2): 84-88.
Abstract:
The type and distribution of fatty acids in the recent marine sediment, peat, Tertiary mud stone ofthe Fusha depression, oil shale of the Maomin basin and a cerise of Tertiary core samples from the east-ern depression of the Liaohe basin were analysed and investigated. As a result, the predominant fattyacids in the bitumen of sediments with planktons as the main input were found to be monocarboxylicacids,whereas more abundanta,cu dicarboxylic acids were found in the sediment with terrigenous highplants as the main input. The relative abundance of long-chain and short-chain acids in fatty acids ofsamples was found to be reducing and increasing, respectively, with increasing evolution of samples. E-limination in the preference of even to odd carbon acids was observed with increasing the evolution ofs am p les,too. The fact that fatty acids in the rock collected at 2266m from the eastern depression of theLiaohe basin are still showing preference of evencardo n to odd cardon demonstrated that the fatty acidswith preference of even to odd cardon can be reserved in sedimentary rocks before they reach to the peakstage of generating hydrocarbons and that the fatty acids in sedimentary rocks can play an important rolefor generating alkanes with preference of odd carhon to even caron in immature oils.
The type and distribution of fatty acids in the recent marine sediment, peat, Tertiary mud stone ofthe Fusha depression, oil shale of the Maomin basin and a cerise of Tertiary core samples from the east-ern depression of the Liaohe basin were analysed and investigated. As a result, the predominant fattyacids in the bitumen of sediments with planktons as the main input were found to be monocarboxylicacids,whereas more abundanta,cu dicarboxylic acids were found in the sediment with terrigenous highplants as the main input. The relative abundance of long-chain and short-chain acids in fatty acids ofsamples was found to be reducing and increasing, respectively, with increasing evolution of samples. E-limination in the preference of even to odd carbon acids was observed with increasing the evolution ofs am p les,too. The fact that fatty acids in the rock collected at 2266m from the eastern depression of theLiaohe basin are still showing preference of evencardo n to odd cardon demonstrated that the fatty acidswith preference of even to odd cardon can be reserved in sedimentary rocks before they reach to the peakstage of generating hydrocarbons and that the fatty acids in sedimentary rocks can play an important rolefor generating alkanes with preference of odd carhon to even caron in immature oils.
1997, 15(2): 105-108.
Abstract:
Immature oils in the Zhaolanzhuang and Zhaoxian oil-fields are generated from Es4-Ek1source rocks(Ro around 0.4%)with gypsum collected form the north-middle Jingxian sag of the Jizhong depression.Characteristics of the immature oil are of high viscosity(0. 98-1.08 g/cm3)and H2S( 6.5%-15%)amount of soluble organic matter is more than 0.2%,the ratio of soluble organic matter total organiccarldn is 55% It has abundant asphaltense, cyclohydrocarbons and isohydrocarbons. n-Alkanes are dom-inated by even carbon. The area has a favorable expulsion condition and bright exploration prospect.
Immature oils in the Zhaolanzhuang and Zhaoxian oil-fields are generated from Es4-Ek1source rocks(Ro around 0.4%)with gypsum collected form the north-middle Jingxian sag of the Jizhong depression.Characteristics of the immature oil are of high viscosity(0. 98-1.08 g/cm3)and H2S( 6.5%-15%)amount of soluble organic matter is more than 0.2%,the ratio of soluble organic matter total organiccarldn is 55% It has abundant asphaltense, cyclohydrocarbons and isohydrocarbons. n-Alkanes are dom-inated by even carbon. The area has a favorable expulsion condition and bright exploration prospect.
1997, 15(2): 114-117.
Abstract:
The buried depth of oil and gas reservoirs is deep and over half of it is distributed in the depth of >4 500 m in the Tarim Basin. Deep burial causes high geopressure which is beneficial to the conservationof oil and gas reservoirs. The geotemperature at 7 000 m depth in the Tarim Basin is lower than 165below the lower limit of oil-generating temperature, so the conservation depth of oil and gas reservoirs can reach to 7 000 m. The Paleozoic craton basin of the Tarim Basin is characterized by the late secondary hydrocarbongeneration, which is important to the oil and gas reservoirs from the Paleozoic source rocks of the TarimBasin. TheRo> value of oil-genrating high peaks is about 1.2%and the range of the oil-generating win-low can be extended to Ro1.5% The Tieling limestone simulation experiment with high temperature and pressure demonstrated thathigh pressure is beneficial to the conservation of liquid hydrocarbons in carbonate rocks and retards the change of oil to gas. The simulation experiment also indicated that in the deeply buried condition the latesecondary hydrocarbon generation can take place in carbonate rocks because of high temperature andpressure.
The buried depth of oil and gas reservoirs is deep and over half of it is distributed in the depth of >4 500 m in the Tarim Basin. Deep burial causes high geopressure which is beneficial to the conservationof oil and gas reservoirs. The geotemperature at 7 000 m depth in the Tarim Basin is lower than 165below the lower limit of oil-generating temperature, so the conservation depth of oil and gas reservoirs can reach to 7 000 m. The Paleozoic craton basin of the Tarim Basin is characterized by the late secondary hydrocarbongeneration, which is important to the oil and gas reservoirs from the Paleozoic source rocks of the TarimBasin. TheRo> value of oil-genrating high peaks is about 1.2%and the range of the oil-generating win-low can be extended to Ro1.5% The Tieling limestone simulation experiment with high temperature and pressure demonstrated thathigh pressure is beneficial to the conservation of liquid hydrocarbons in carbonate rocks and retards the change of oil to gas. The simulation experiment also indicated that in the deeply buried condition the latesecondary hydrocarbon generation can take place in carbonate rocks because of high temperature andpressure.
1997, 15(2): 122-125.
Abstract:
Kinetic parameters of kerogen pyrolysis have been widely used in basin modelling. Because the de-tection of gas products is more difficult than that of liquid products in thermal simulation experiments,the study of natural gas generation is random. The combination of TG( thermogravimetric)analysis with Fourier transform infrared(FTIR) spec-troscopy analysis was used to analyze different coal macerals and detect the pyrolysis products. The powdered samples were grogerssively heatedcatra to of 25℃/minute) and weighted in theT G A. A carrier gas transported the effluent through a multipass gas cell for continuos analysis by FTIRSelected infrared absorption bands were used to detect different compounds. Data were captured foraliphatics, aromatics, cardon dioxide and methane. The analytical results indicated that different coal macerals have different characters in pyrolysis. Hydrocarbon generation can be modelled by assuming that a number of parallel first grder reactions control the thermal decomposition of kerogen. Issler's optimization software was used to derive kineticparameters from the digitized pyrolysis traces. Kinetic solutions from TGA-FTIR data yield equations forspecial products. Inputting this equatioins into a numerical modelling package such as BASINMO D, alongwith other information, the generation of methane, aliphatics etc.coilld be predicted.
Kinetic parameters of kerogen pyrolysis have been widely used in basin modelling. Because the de-tection of gas products is more difficult than that of liquid products in thermal simulation experiments,the study of natural gas generation is random. The combination of TG( thermogravimetric)analysis with Fourier transform infrared(FTIR) spec-troscopy analysis was used to analyze different coal macerals and detect the pyrolysis products. The powdered samples were grogerssively heatedcatra to of 25℃/minute) and weighted in theT G A. A carrier gas transported the effluent through a multipass gas cell for continuos analysis by FTIRSelected infrared absorption bands were used to detect different compounds. Data were captured foraliphatics, aromatics, cardon dioxide and methane. The analytical results indicated that different coal macerals have different characters in pyrolysis. Hydrocarbon generation can be modelled by assuming that a number of parallel first grder reactions control the thermal decomposition of kerogen. Issler's optimization software was used to derive kineticparameters from the digitized pyrolysis traces. Kinetic solutions from TGA-FTIR data yield equations forspecial products. Inputting this equatioins into a numerical modelling package such as BASINMO D, alongwith other information, the generation of methane, aliphatics etc.coilld be predicted.
1997, 15(2): 130-133.
Abstract:
The new compositional models of hydrocarbon generation in and expulsion from source rocks wereproposed in this paper. The compositional model of hydrocarbon generation is based on the com posi do nalproductivity of source rocks vs. thermal maturity derived from thermal simulation experiment in labora-tory. The compositional model of hydrocarbon expulsion includes open system model and intermittentlyopen system model. The open system model describes the process of hydrocarbon expulsion throughpores of source rocks forced by compaction,and the intermittently open system model describes the pro-cess of hydrocarbon expulsion through microfractures forced by abnormally high fluid pressure. The changes of fluid volume and phases in the pore system and the distribution of hydrocarbon compositionsin different phases were calculated with thermodynaer cprinciples based on the temperature pressureand the fluid composition in the pore system. Thus, the expulsion history of hydrocarbon compositionsand the total expulsion amount can be simulated based on the difference between fluid volume and porevolume of source rocks and the distribution of hydrocarbon compositions in different phases. The resultof these models applied to the Paleozoic of the Ordos basin has shown the practical value of the models.
The new compositional models of hydrocarbon generation in and expulsion from source rocks wereproposed in this paper. The compositional model of hydrocarbon generation is based on the com posi do nalproductivity of source rocks vs. thermal maturity derived from thermal simulation experiment in labora-tory. The compositional model of hydrocarbon expulsion includes open system model and intermittentlyopen system model. The open system model describes the process of hydrocarbon expulsion throughpores of source rocks forced by compaction,and the intermittently open system model describes the pro-cess of hydrocarbon expulsion through microfractures forced by abnormally high fluid pressure. The changes of fluid volume and phases in the pore system and the distribution of hydrocarbon compositionsin different phases were calculated with thermodynaer cprinciples based on the temperature pressureand the fluid composition in the pore system. Thus, the expulsion history of hydrocarbon compositionsand the total expulsion amount can be simulated based on the difference between fluid volume and porevolume of source rocks and the distribution of hydrocarbon compositions in different phases. The resultof these models applied to the Paleozoic of the Ordos basin has shown the practical value of the models.
1997, 15(2): 138-141.
Abstract:
In this paper, the thermal simulation experiments on the koregen degradation of sauce rocks werecarried out by using pyrolysis gas chromatography. The isothermal experimental data were used to de-velop a kinetic model of oil and gas generation. A new method based on the kinetic reaction theory wasproposed which offers a quantitative approach to the evaluation of natural gas and petroleum. As an ex-ample, the fraction and intensity of the natural gas and petroleum generation were calculated for the dif-ferent burial units of the typical wells in the Turpan-Hamibasin.
In this paper, the thermal simulation experiments on the koregen degradation of sauce rocks werecarried out by using pyrolysis gas chromatography. The isothermal experimental data were used to de-velop a kinetic model of oil and gas generation. A new method based on the kinetic reaction theory wasproposed which offers a quantitative approach to the evaluation of natural gas and petroleum. As an ex-ample, the fraction and intensity of the natural gas and petroleum generation were calculated for the dif-ferent burial units of the typical wells in the Turpan-Hamibasin.
1997, 15(2): 145-149.
Abstract:
Using the thin layer chromatoraphy /flame ioniertion detector( TLC-FID) coupled with the oil showanaly zer(OSA),the Carboniferous cores from three wells on the Tazhong 4 structure were densely cal-lected and analy sed(about 3 /m),while typical oil samples selected were analysed by GC GC/MS and cardonisotope analysis. The study indicated that thegross composition of residual oils exists an obviousheterogeneities either vertically or laterally. The C group can be divided into three layers CⅢ1(oillay er)CⅢ2,CⅢ3(oil-water lay ers)·It was considered that local layers with high oil saturation within CⅢ2,CⅢ3 are of value to test oil and that the primary petroleum reservoir could be destroyed by the Himalayanmovement and petroleum of CⅢ3 was redistributed again from west to east. then the petroleum of CⅢ2flowed out along the fault and the oil-water system which has two palaeo-oil-water contacts was formed.According to the lateral maturity variation, it was considered that the filling direction of the main oilsource from the Lower Palaeo zoi c is tentatively from west-north to east-sorth. But data of chromatographic analysis and the valueof carbon isotopes of oils suggested that another type of oil from asubsidiarysou rcein the Upper Palaeozoic fill in the structural high 1on the TZ4 stmcture.
Using the thin layer chromatoraphy /flame ioniertion detector( TLC-FID) coupled with the oil showanaly zer(OSA),the Carboniferous cores from three wells on the Tazhong 4 structure were densely cal-lected and analy sed(about 3 /m),while typical oil samples selected were analysed by GC GC/MS and cardonisotope analysis. The study indicated that thegross composition of residual oils exists an obviousheterogeneities either vertically or laterally. The C group can be divided into three layers CⅢ1(oillay er)CⅢ2,CⅢ3(oil-water lay ers)·It was considered that local layers with high oil saturation within CⅢ2,CⅢ3 are of value to test oil and that the primary petroleum reservoir could be destroyed by the Himalayanmovement and petroleum of CⅢ3 was redistributed again from west to east. then the petroleum of CⅢ2flowed out along the fault and the oil-water system which has two palaeo-oil-water contacts was formed.According to the lateral maturity variation, it was considered that the filling direction of the main oilsource from the Lower Palaeo zoi c is tentatively from west-north to east-sorth. But data of chromatographic analysis and the valueof carbon isotopes of oils suggested that another type of oil from asubsidiarysou rcein the Upper Palaeozoic fill in the structural high 1on the TZ4 stmcture.
1997, 15(2): 155-159.
Abstract:
The planar fluid distribution of Cardomifero us v olcani c reservoi rs i n the Shixi Oilfi eld show s a re-markable trend i. e crude oil becomes heavier from south to north and its properties are not contro liedby the structure. There is difference between the formation water in the eastern and western parts. Theformation water has a lower salinity in the western part with gradient of ion concentration increasingform south to north while ion has a higher salinity in the east with gradient of ion concentration increas-ing from west to south. Asynthetic study indicated that the migration or injection direction of formationwater and crude oils is from south to noth and faults in the central part of reservoirs separated the dstri-bution of formation water and faults into two parts, and then affected oil and gas productivity.
The planar fluid distribution of Cardomifero us v olcani c reservoi rs i n the Shixi Oilfi eld show s a re-markable trend i. e crude oil becomes heavier from south to north and its properties are not contro liedby the structure. There is difference between the formation water in the eastern and western parts. Theformation water has a lower salinity in the western part with gradient of ion concentration increasingform south to north while ion has a higher salinity in the east with gradient of ion concentration increas-ing from west to south. Asynthetic study indicated that the migration or injection direction of formationwater and crude oils is from south to noth and faults in the central part of reservoirs separated the dstri-bution of formation water and faults into two parts, and then affected oil and gas productivity.
1997, 15(2): 164-168.
Abstract:
Study of a series of 125 coal and source rock samples ranging in rank from the brown coal to lowvolatile bi tomono us coal in different regions and ages of China revealed that vitrinite fluorescence is con-trolled not only by rank, but also by vitrinite type. The fluorescence intensity of huminites dereases dras-tically to the Ro stage of 0. 40y 0. 5070,thereafter the secondary fluorescence of the orthohydrous vit-rinites begins to develop, fluorescence intensity of the orthohydrous vitrinite increases with coal rank,reaching the maximum at the Ro stage of 0. 85-1.0%.There is significant difference of fluorescenceproperties in different types of vitrinites in the stage of oil window,the fluorescence intensity of the per-hydrous vitrinite is obviously higher than that of the orthohydrous vitrinite. The fluorescence intensity ofthe pethydrous vitrinite remains relatively high in the Ro stage of 0. 40%一0. 85%,independent of coalrank. There is no minimum of fluorescence intensity at the stage about 0.45% R for the perhydrous vit-rinite,which is different from the orthohydrous vitrinite. The peculiar fluorescence properties of the per-hydrous vitrinite were interpreted by relatively abundant submicroliptinites and high amounts of mobilephase in vitrinites according to the positive correlation omong fluorescence intensity of vitriites,amounts of suhmicroliptinite in vitrinites and chloroform extracted yields.
Study of a series of 125 coal and source rock samples ranging in rank from the brown coal to lowvolatile bi tomono us coal in different regions and ages of China revealed that vitrinite fluorescence is con-trolled not only by rank, but also by vitrinite type. The fluorescence intensity of huminites dereases dras-tically to the Ro stage of 0. 40y 0. 5070,thereafter the secondary fluorescence of the orthohydrous vit-rinites begins to develop, fluorescence intensity of the orthohydrous vitrinite increases with coal rank,reaching the maximum at the Ro stage of 0. 85-1.0%.There is significant difference of fluorescenceproperties in different types of vitrinites in the stage of oil window,the fluorescence intensity of the per-hydrous vitrinite is obviously higher than that of the orthohydrous vitrinite. The fluorescence intensity ofthe pethydrous vitrinite remains relatively high in the Ro stage of 0. 40%一0. 85%,independent of coalrank. There is no minimum of fluorescence intensity at the stage about 0.45% R for the perhydrous vit-rinite,which is different from the orthohydrous vitrinite. The peculiar fluorescence properties of the per-hydrous vitrinite were interpreted by relatively abundant submicroliptinites and high amounts of mobilephase in vitrinites according to the positive correlation omong fluorescence intensity of vitriites,amounts of suhmicroliptinite in vitrinites and chloroform extracted yields.
1997, 15(2): 173-178.
Abstract:
tential of different assemblages of macerals was studied. The hydrocarbon potential per unit orgyi ccar-bon of the exino}itrinites is high which proves the oil and gas prospect in the PRM B.Coal petrographjcal identification and fluorescence testing for organic macerals of Paleogene sour cerrocks in the Pearl River Mouth Basin( PRMB) were carried out by using com prehersive microscopymethod of combining transmitted light, reflected light and fluorescent light. The new technology ofTransmitted Electronic Microscope( TEM)was also applied to study ultramicroliptinites invitrinites. Py-rolysis simulation was used to evaluate the hydrocarbon potential of source rocks with different composi-dons of organic macerals.(1),A unique feature of macerals in the studied area was discovered, i. e. richexinites and sapropellinites are endedded in the vitrinite, and a new name, exino-vitrinite was given forthis kind of maceral. The exino-vitrinite was further divided into submacerals through integrating finerdivision of the amorphous;(2),Ultramicroliptinites were identified and quantitated under the highfoklT EM;(3),The source rocks were classified into three types and seven assemblages of organic ma corals,Among them the assenblages of A2 and Bi are the primary ones, Bz the secondary. The exino-vitrinitesand ultramicroliptinites are the main hydrocarbon generating matter in the basin.(4),Hydrocarbon po
tential of different assemblages of macerals was studied. The hydrocarbon potential per unit orgyi ccar-bon of the exino}itrinites is high which proves the oil and gas prospect in the PRM B.Coal petrographjcal identification and fluorescence testing for organic macerals of Paleogene sour cerrocks in the Pearl River Mouth Basin( PRMB) were carried out by using com prehersive microscopymethod of combining transmitted light, reflected light and fluorescent light. The new technology ofTransmitted Electronic Microscope( TEM)was also applied to study ultramicroliptinites invitrinites. Py-rolysis simulation was used to evaluate the hydrocarbon potential of source rocks with different composi-dons of organic macerals.(1),A unique feature of macerals in the studied area was discovered, i. e. richexinites and sapropellinites are endedded in the vitrinite, and a new name, exino-vitrinite was given forthis kind of maceral. The exino-vitrinite was further divided into submacerals through integrating finerdivision of the amorphous;(2),Ultramicroliptinites were identified and quantitated under the highfoklT EM;(3),The source rocks were classified into three types and seven assemblages of organic ma corals,Among them the assenblages of A2 and Bi are the primary ones, Bz the secondary. The exino-vitrinitesand ultramicroliptinites are the main hydrocarbon generating matter in the basin.(4),Hydrocarbon po
1997, 15(2): 188-191.
Abstract:
A new unknow n compound(arbitrarily labelled”E here) was detected out in sediments and conden-sates from the Ying-Qing Basin, South China Sea. The component is in significantly high abundance in certain samples, and it elutes after 17β(H)一22, 29, 30-trinorhopane in m /z 191 fragmentogram and justafter C28 5α(H),17α(H),21α(H) sterane(22S) in m/z,218 fragmentogram. The spectrum of ompound”E”indicated that compound E is a C29 tetracyclic compound. GC/M S/M S analysis demonstrated thatfragment ions at m /z 191, 218 and 273 do belong to the compound”E".To the best of our knowledge,the compound E is first reported too ccur in sedimentary records. The presence of the compound E is in-ferred to be related to marine organic matter input, which may be a product of specific algal precursorsin a trophic marine depositional environment. In addition to environment significance, the relative con-centration of the compound E in rock extracts was observed to be dependent on the maturity of rocks.
A new unknow n compound(arbitrarily labelled”E here) was detected out in sediments and conden-sates from the Ying-Qing Basin, South China Sea. The component is in significantly high abundance in certain samples, and it elutes after 17β(H)一22, 29, 30-trinorhopane in m /z 191 fragmentogram and justafter C28 5α(H),17α(H),21α(H) sterane(22S) in m/z,218 fragmentogram. The spectrum of ompound”E”indicated that compound E is a C29 tetracyclic compound. GC/M S/M S analysis demonstrated thatfragment ions at m /z 191, 218 and 273 do belong to the compound”E".To the best of our knowledge,the compound E is first reported too ccur in sedimentary records. The presence of the compound E is in-ferred to be related to marine organic matter input, which may be a product of specific algal precursorsin a trophic marine depositional environment. In addition to environment significance, the relative con-centration of the compound E in rock extracts was observed to be dependent on the maturity of rocks.
1997, 15(2): 198-201.
Abstract:
The distribution characteristics of the aromatic hydrocarbons of Jurassic coal-measures sourrocksfrom the Turpan-Hami basin were been systematically studied in this paper. The results indicated thatoiler enerati ng cowls from the Turpan-Hamibasin had been formed in special sedimentary environmentsof coal-measures. The organic matter of coal-measures source rocks mainly came from higher plants,partly from lower aquatic living things, such as algae. The sedimentary environments of the co al-m ca-cures were mainly lake-marsh fades, freshwater emisalt water, weakty reducing-reducing environ-menu.
The distribution characteristics of the aromatic hydrocarbons of Jurassic coal-measures sourrocksfrom the Turpan-Hami basin were been systematically studied in this paper. The results indicated thatoiler enerati ng cowls from the Turpan-Hamibasin had been formed in special sedimentary environmentsof coal-measures. The organic matter of coal-measures source rocks mainly came from higher plants,partly from lower aquatic living things, such as algae. The sedimentary environments of the co al-m ca-cures were mainly lake-marsh fades, freshwater emisalt water, weakty reducing-reducing environ-menu.
1997, 15(2): 212-215.
Abstract:
Carbon isotope research on the characteristics of nC15 N-alkane elements in different types of as-phaltic residues from hydrocarbon source rock reveals a rich 12C property of caro bn i so topic com posi do nfor nC15 N-alkane elements in marine carbonate source rock of Palaeozoic and lacustrine-facies argilla-ceons source rock of Mesozoic as well as a rich 13C property for N-flkane elements in paludal faciessapro
Carbon isotope research on the characteristics of nC15 N-alkane elements in different types of as-phaltic residues from hydrocarbon source rock reveals a rich 12C property of caro bn i so topic com posi do nfor nC15 N-alkane elements in marine carbonate source rock of Palaeozoic and lacustrine-facies argilla-ceons source rock of Mesozoic as well as a rich 13C property for N-flkane elements in paludal faciessapro
1997, 15(2): 220-225.
Abstract:
Large area of the Erlian Basin has been investigated with the method of surface geochemicalprospecting for searching oil and gas. In this article, these data obtained were re-processed carelly andreanalysed under the combination with other gelolgical data. Thus the models of surface geochemical ab-normalities were summarized,and all methods used in the Erlian Basin were evaluated. Also effect analy-sis of geochemical prospecting in the Erlian Basin was made.Large area of the Erlian Basin has been investigated with the method of surface geochemicalprospecting for searching oil and gas. In this article, these data obtained were re-processed carelly andreanalysed under the combination with other gelolgical data. Thus the models of surface geochemical ab-normalities were summarized,and all methods used in the Erlian Basin were evaluated. Also effect analy-sis of geochemical prospecting in the Erlian Basin was made.
Large area of the Erlian Basin has been investigated with the method of surface geochemicalprospecting for searching oil and gas. In this article, these data obtained were re-processed carelly andreanalysed under the combination with other gelolgical data. Thus the models of surface geochemical ab-normalities were summarized,and all methods used in the Erlian Basin were evaluated. Also effect analy-sis of geochemical prospecting in the Erlian Basin was made.Large area of the Erlian Basin has been investigated with the method of surface geochemicalprospecting for searching oil and gas. In this article, these data obtained were re-processed carelly andreanalysed under the combination with other gelolgical data. Thus the models of surface geochemical ab-normalities were summarized,and all methods used in the Erlian Basin were evaluated. Also effect analy-sis of geochemical prospecting in the Erlian Basin was made.
1997, 15(2): 232-235.
Abstract:
The hydrological character and water quality of the Pearler in Guangou are greatly affected bytidal action. In the Pearl River the west channel and the Liuxi river, as main water sources inGuangzhou, are in the upstream of the urban city of Guangzhou, and their water quality is greatly dete-riorated by the heavily polluted water going upstream from down stream due to tidal action, so it is ofgreat importance to investigate in what degree and in what range the source water quality is influencedby tidal action for the purpose of the protection and utilization of water resources. This paper carried outanalyses of the organic matter in bottom sediments from down stream to upstream in the water sourcearea, and was a biomarker approach to the influence of tidal action, the results revealed that tidal actionhas little influence on the water quality in the upstream of Yagang; but in Xicen and Shimen, there ex-fists obvious influence of tidal action on the water body, organic matter is caracterized by sources frompollution by human activities. The study also indicated that principles and methods organic geochemistry could be applied to the study on hydrological features and water quality in the river system.
The hydrological character and water quality of the Pearler in Guangou are greatly affected bytidal action. In the Pearl River the west channel and the Liuxi river, as main water sources inGuangzhou, are in the upstream of the urban city of Guangzhou, and their water quality is greatly dete-riorated by the heavily polluted water going upstream from down stream due to tidal action, so it is ofgreat importance to investigate in what degree and in what range the source water quality is influencedby tidal action for the purpose of the protection and utilization of water resources. This paper carried outanalyses of the organic matter in bottom sediments from down stream to upstream in the water sourcearea, and was a biomarker approach to the influence of tidal action, the results revealed that tidal actionhas little influence on the water quality in the upstream of Yagang; but in Xicen and Shimen, there ex-fists obvious influence of tidal action on the water body, organic matter is caracterized by sources frompollution by human activities. The study also indicated that principles and methods organic geochemistry could be applied to the study on hydrological features and water quality in the river system.
1997, 15(2): 6-13.
Abstract:
Part of oils generated from the M anjiar depression has medium to high wax content. Based on thedistribution of the wax content of oils, analysis of biomakers in bacteria and algae and the results of sim-ulation experiments, it was considered that the high wax content in the oils from the Lower Paleozoic ofthe both south and north uplifts in the Manjiar depression is chiefly related to algae,due green algae andbacteria which aenthe main organic origin in the Lower Paleozoic·of the tended isoprenoids and hopanoids originated from blue green algae and bacteria were fornd in tracts and oils. Extendedn alkanes also existed in the pyrolytic products of recent plankton blue green algae. Abundance ofwaxy n}-akanes could also be caused by the geochromatographic effects during migration.
Part of oils generated from the M anjiar depression has medium to high wax content. Based on thedistribution of the wax content of oils, analysis of biomakers in bacteria and algae and the results of sim-ulation experiments, it was considered that the high wax content in the oils from the Lower Paleozoic ofthe both south and north uplifts in the Manjiar depression is chiefly related to algae,due green algae andbacteria which aenthe main organic origin in the Lower Paleozoic·of the tended isoprenoids and hopanoids originated from blue green algae and bacteria were fornd in tracts and oils. Extendedn alkanes also existed in the pyrolytic products of recent plankton blue green algae. Abundance ofwaxy n}-akanes could also be caused by the geochromatographic effects during migration.
1997, 15(2): 19-25.
Abstract:
This paper dealt with that oils from tow Paleogene oil systems in Jiangling Depression have greatlydifferent geochemical properties due to different source matter and different maturities of two sets of hy-drocarbon source rocks. In the first oil system, the principal souce sequence is ranging from the middleand lower parts and the upper partor the mudstone, barrier in the formation, it is of medium to goodsource rock and has generated relatively abundant hydrocarbons. Studies showed that in different areasor zones this oil system has two different oil souse models, i. e. oueis, the system itself alone; the other isthe system with allochthonous source. Oil migration distance may he as far as over 10 km. The source models and migration distance arebasically responsible for the distribution of Xingouzui. Formation and Jingsha Formation oil reservoirs.In the second oil system,source rocks in Qianjiang Formation, though being shallowly buried less than2000 m(Ro<0.5%),had been found to haven high abundance of organic matter in the 3rd and 4th mem-hers of Qianjiang Formation. kerogens are of Typel and Typel S, having the potential to generate im-mature oil inshould he paidearly stage of transformation, soas to constitute oil reservoirs in situ.Properattentiont should be paid to them in exploration.
This paper dealt with that oils from tow Paleogene oil systems in Jiangling Depression have greatlydifferent geochemical properties due to different source matter and different maturities of two sets of hy-drocarbon source rocks. In the first oil system, the principal souce sequence is ranging from the middleand lower parts and the upper partor the mudstone, barrier in the formation, it is of medium to goodsource rock and has generated relatively abundant hydrocarbons. Studies showed that in different areasor zones this oil system has two different oil souse models, i. e. oueis, the system itself alone; the other isthe system with allochthonous source. Oil migration distance may he as far as over 10 km. The source models and migration distance arebasically responsible for the distribution of Xingouzui. Formation and Jingsha Formation oil reservoirs.In the second oil system,source rocks in Qianjiang Formation, though being shallowly buried less than2000 m(Ro<0.5%),had been found to haven high abundance of organic matter in the 3rd and 4th mem-hers of Qianjiang Formation. kerogens are of Typel and Typel S, having the potential to generate im-mature oil inshould he paidearly stage of transformation, soas to constitute oil reservoirs in situ.Properattentiont should be paid to them in exploration.
1997, 15(2): 35-39.
Abstract:
In the southwest depression, Tarim basin, the oil from the Qu一and Mai-3 wells in the Bashentuopuoil field w as pos Tulated too rigina to from Cam b rianrdovician hydrocarbon source rocks, while that ofthe Mai一3 well was slightly mingled with Carboniferous hydrocarbons; it was believed that the naturalgas from the Qu一3 well is liptinite-type gas which is derived from Cambriand ovician source rocks. Inokeya condensate oil and gas field(including oil and gas shallow in the Xihefu group and deep alataergroup),the oil and gas(ov erma turemixed type genesis) were the mixed products from Carboniferous-Permian and Mid-Lower Jurassic source beds,and the former is dominant.
In the southwest depression, Tarim basin, the oil from the Qu一and Mai-3 wells in the Bashentuopuoil field w as pos Tulated too rigina to from Cam b rianrdovician hydrocarbon source rocks, while that ofthe Mai一3 well was slightly mingled with Carboniferous hydrocarbons; it was believed that the naturalgas from the Qu一3 well is liptinite-type gas which is derived from Cambriand ovician source rocks. Inokeya condensate oil and gas field(including oil and gas shallow in the Xihefu group and deep alataergroup),the oil and gas(ov erma turemixed type genesis) were the mixed products from Carboniferous-Permian and Mid-Lower Jurassic source beds,and the former is dominant.
1997, 15(2): 45-48.
Abstract:
Based on the residual hydrocarbon content in source rocks and the developed new parameters of ma-turity in the rock-oval computer system,this paper presented a recovery mathod for the abundance of pri-mart' organic matter in low to high-mature source rocks( any abundance, type and lithology).It is knownas the residual hydrocarbon method. Based on the data from rock pyrolytic and organic carbon analyseswith the basic principles in sedimentology and organic petrology, on the theory of oil generation of kero-gen decomposition, and on three defiidons and an acknowledged hypothesis which researchers oftenuse, this paper presected a recovery method of the abundance of primary organic matter for low to over-mature sour cerrocks(any maturity,abundance, type and lithology).It is known as the organic ineffective carbon method. because the content of the organic ineffective card on has nothing to do with the evolu-tional degree of source rocks, this method is applicable to the recovery of the abundance of the primaryorganic matter for source rocks with any maturity,especially to solve the recovery of the abundance ofthe primary organic matter for high or over-mature source rocks.
Based on the residual hydrocarbon content in source rocks and the developed new parameters of ma-turity in the rock-oval computer system,this paper presented a recovery mathod for the abundance of pri-mart' organic matter in low to high-mature source rocks( any abundance, type and lithology).It is knownas the residual hydrocarbon method. Based on the data from rock pyrolytic and organic carbon analyseswith the basic principles in sedimentology and organic petrology, on the theory of oil generation of kero-gen decomposition, and on three defiidons and an acknowledged hypothesis which researchers oftenuse, this paper presected a recovery method of the abundance of primary organic matter for low to over-mature sour cerrocks(any maturity,abundance, type and lithology).It is known as the organic ineffective carbon method. because the content of the organic ineffective card on has nothing to do with the evolu-tional degree of source rocks, this method is applicable to the recovery of the abundance of the primaryorganic matter for source rocks with any maturity,especially to solve the recovery of the abundance ofthe primary organic matter for high or over-mature source rocks.
1997, 15(2): 63-65.
Abstract:
Mixing of gases from different origins is universal phenomenon in nature. The concentration ofeach component in the gas mixtureis the sum of all the volume ratio.The relationship of isotopic compositronscomponent mixed in the mixture weighted byofltsand ratioes was verified in the laboratory. Its ap-plication to the Hexiwu structure zone in the Lang-Gu depression showed 24-63 percentage of the gasesis from the Cardorriferous and Perenan coal system.
Mixing of gases from different origins is universal phenomenon in nature. The concentration ofeach component in the gas mixtureis the sum of all the volume ratio.The relationship of isotopic compositronscomponent mixed in the mixture weighted byofltsand ratioes was verified in the laboratory. Its ap-plication to the Hexiwu structure zone in the Lang-Gu depression showed 24-63 percentage of the gasesis from the Cardorriferous and Perenan coal system.
1997, 15(2): 75-83.
Abstract:
Based on a detailed literature investigation into the generation and occurrence of Chinese and inter-national immature crude oils, the authors selected 9 Tertary sedimentary sags as typical cuses for system-atic analysis and study in combination with the comparative study of typical crude oils and source rocksfrom 5 M eso Cenozoic medium to small size sedimentary basins in China, totally 102 wells and relatedsurface or coal mine sections were involved and 33 oil and 563 rock samples were collected f o r o rganicgeocheen cal, organic petrological and isotopic geocheen cal analyses, altogether 24 different analyticaltechniques were used and plentiful experimental data were obtained, in the basis of which, 5 geneticmechanisms of early generation for immature crude oils, i. e.,hydrocarbons derived from subrinite, resi-nite, bacteria-reworked terrestrial organic metter, algal and higher plant biolipids as well as sulfur-rchromolecules(such as non}ydrocarbons,asphaltenes and Typell kerogen),were proposed.
Based on a detailed literature investigation into the generation and occurrence of Chinese and inter-national immature crude oils, the authors selected 9 Tertary sedimentary sags as typical cuses for system-atic analysis and study in combination with the comparative study of typical crude oils and source rocksfrom 5 M eso Cenozoic medium to small size sedimentary basins in China, totally 102 wells and relatedsurface or coal mine sections were involved and 33 oil and 563 rock samples were collected f o r o rganicgeocheen cal, organic petrological and isotopic geocheen cal analyses, altogether 24 different analyticaltechniques were used and plentiful experimental data were obtained, in the basis of which, 5 geneticmechanisms of early generation for immature crude oils, i. e.,hydrocarbons derived from subrinite, resi-nite, bacteria-reworked terrestrial organic metter, algal and higher plant biolipids as well as sulfur-rchromolecules(such as non}ydrocarbons,asphaltenes and Typell kerogen),were proposed.
1997, 15(2): 95-99.
Abstract:
The Turpan-Hami basin is a typical basin in which hydrocarbons are derived from coalg and main source rocks are coalwith coaly organic matters in the Lower-Middle Jurassic.The analysis of organic petrology showed that the composition ofmaceraLs is of characteristic of the high content of groundmass maceraLs(such as desmocnllinite, macrinite),small individu-als of sporinite and alginite and higher contents of transition macerals(such as vitrinite inertinite desmoc;olHnite and bitu-minite).By mean of nucroscopy, laser microscopy and transmitting electronic microscopy(TEM),it was shown that themain oilg-generating maceraLs are desmocollinite under microscopic observation. Liptodetrinite,。utinite, suberinite and spori-nite have important contributions to thehydro carbon from coal; Under TEM the main oil generating mac}ral is the submi-croliptinite attered in desmoconite and macrinite and it is originated from degraded materials of bacteria. The high con-tent of desmoc collinite in coal remedies its lower hydrocarbon generation potential per unit The cause of hydrogen ric;hnessindesmoc;ollinite attributes to strong degradation and reworking of bacteria to it in the biocthemical stage.
The Turpan-Hami basin is a typical basin in which hydrocarbons are derived from coalg and main source rocks are coalwith coaly organic matters in the Lower-Middle Jurassic.The analysis of organic petrology showed that the composition ofmaceraLs is of characteristic of the high content of groundmass maceraLs(such as desmocnllinite, macrinite),small individu-als of sporinite and alginite and higher contents of transition macerals(such as vitrinite inertinite desmoc;olHnite and bitu-minite).By mean of nucroscopy, laser microscopy and transmitting electronic microscopy(TEM),it was shown that themain oilg-generating maceraLs are desmocollinite under microscopic observation. Liptodetrinite,。utinite, suberinite and spori-nite have important contributions to thehydro carbon from coal; Under TEM the main oil generating mac}ral is the submi-croliptinite attered in desmoconite and macrinite and it is originated from degraded materials of bacteria. The high con-tent of desmoc collinite in coal remedies its lower hydrocarbon generation potential per unit The cause of hydrogen ric;hnessindesmoc;ollinite attributes to strong degradation and reworking of bacteria to it in the biocthemical stage.
1997, 15(2): 109-113.
Abstract:
The evolution feature of hydrocarbon source rocks are different with various types(mono cycledouble cycles) of rift basins of Late Mesozoic in the peripheral area of Liaohe Basin. Based upon the hy-drocarbon source rocks of different types of basins, their evolution curve was analyzed through basinmodelling. Three evolution patterns were raised and the oil reservoir characteristics under different pat-terns were discussed as well.
The evolution feature of hydrocarbon source rocks are different with various types(mono cycledouble cycles) of rift basins of Late Mesozoic in the peripheral area of Liaohe Basin. Based upon the hy-drocarbon source rocks of different types of basins, their evolution curve was analyzed through basinmodelling. Three evolution patterns were raised and the oil reservoir characteristics under different pat-terns were discussed as well.
1997, 15(2): 118-121.
Abstract:
It isn t very satisfactory to explain the hydrocarbon formation in carbonate rocks with thermal evo-lution of kerogen. In this paper a tentative viewpoint was proposed that there is a kind of potential hy-drocarbon generation matters(salt of fatty acid)in carbonate rocks,for it is of special physical and chemi-cal properties, it is very difficult to obtain the pure salt of fatty acid from sedimentary formation. Thus,we prepared magnesium stearate by chemical synthesis. Magnesium stearte, stearic acid and magnesiumstearate plus CaCO3 were used as simulation samples at 3000℃and 3500℃.The results of the simulationindicated that hydrocarbon conversion ratio of magnesium stearate is higher than that of tearic acid. Thedistribution of reaction products suggested that alpha cleavage is predominant process, in the meantime,βandγ-cracking has also an obvious preponderance. From the experiments of the salt of fatty acid, thenew enlightenment will be gained about hydrocarbon generation in carbonate rocks.
It isn t very satisfactory to explain the hydrocarbon formation in carbonate rocks with thermal evo-lution of kerogen. In this paper a tentative viewpoint was proposed that there is a kind of potential hy-drocarbon generation matters(salt of fatty acid)in carbonate rocks,for it is of special physical and chemi-cal properties, it is very difficult to obtain the pure salt of fatty acid from sedimentary formation. Thus,we prepared magnesium stearate by chemical synthesis. Magnesium stearte, stearic acid and magnesiumstearate plus CaCO3 were used as simulation samples at 3000℃and 3500℃.The results of the simulationindicated that hydrocarbon conversion ratio of magnesium stearate is higher than that of tearic acid. Thedistribution of reaction products suggested that alpha cleavage is predominant process, in the meantime,βandγ-cracking has also an obvious preponderance. From the experiments of the salt of fatty acid, thenew enlightenment will be gained about hydrocarbon generation in carbonate rocks.
1997, 15(2): 126-129.
Abstract:
Based on the data obtained from the combination of constantly heating rate pyrolysis and PY一GCand by the method of mathematical optimum algorithm,the themical kinetic models of the oil and gasgenerated from the coal orgyi cmatter in the Taibei seg were constructed and calibrated in this paper.Combined with the chemical kinetical model of the hydrocarbon generation by suberinite that was report-ed recently,the theoretical profiles of oils generated from kerogen and suberinite were calculated quanti-tativ ely,and a number of problems on the sourec rock evaluation in the Talbei seg of the Turpan-Hamibasin, sucn as the early hydrocarbon generation from suberinite, recovery of the original hydrocarbon po-tential and original abundance of organic matter,as well as the threshold of hydrocarbon generation, werefurther studied quantitativdy in the paper.
Based on the data obtained from the combination of constantly heating rate pyrolysis and PY一GCand by the method of mathematical optimum algorithm,the themical kinetic models of the oil and gasgenerated from the coal orgyi cmatter in the Taibei seg were constructed and calibrated in this paper.Combined with the chemical kinetical model of the hydrocarbon generation by suberinite that was report-ed recently,the theoretical profiles of oils generated from kerogen and suberinite were calculated quanti-tativ ely,and a number of problems on the sourec rock evaluation in the Talbei seg of the Turpan-Hamibasin, sucn as the early hydrocarbon generation from suberinite, recovery of the original hydrocarbon po-tential and original abundance of organic matter,as well as the threshold of hydrocarbon generation, werefurther studied quantitativdy in the paper.
1997, 15(2): 134-137.
Abstract:
The Ordos basin and Qinshui basin, separated by the Iia lung uplift, are all large sdlimerto rybasins. It was detererned by many methods of vitrinite reflectance apatite fission track and fluid inclu-sign that paleogeothermal gradient and heat flow are 3.3-4.3℃/100 m and 81-95 m W/2in the Or-dos basin, 5.8℃/100 m and 106 m W/2in the Qinshui basin, and the Qinshui basin is higher is thesevalues than the Ordos basin. Those facts showed that there was a tectonic一hermal event in Late Meso一wic which occurred from Late Jurassic to Early Cretaceous. this tectoni cthermal event increased ther-mometamorphic degree of Palaeowic gas source rocks and ac elerated gas generation.
The Ordos basin and Qinshui basin, separated by the Iia lung uplift, are all large sdlimerto rybasins. It was detererned by many methods of vitrinite reflectance apatite fission track and fluid inclu-sign that paleogeothermal gradient and heat flow are 3.3-4.3℃/100 m and 81-95 m W/2in the Or-dos basin, 5.8℃/100 m and 106 m W/2in the Qinshui basin, and the Qinshui basin is higher is thesevalues than the Ordos basin. Those facts showed that there was a tectonic一hermal event in Late Meso一wic which occurred from Late Jurassic to Early Cretaceous. this tectoni cthermal event increased ther-mometamorphic degree of Palaeowic gas source rocks and ac elerated gas generation.
1997, 15(2): 142-144.
Abstract:
The thermal history of a single well in Tazhong Area, Tarim basin, was investigated based on the a-petite fission track analysis(AFTA) and spin density of free radicals in kengen, at the same time, the complex evolution of structure and burial history were also studied combining the results of wave-geo-logical analysis. The effect of the complex structural movement to hydrocarbon generation and reservoirformation was discussed. The results of the study revealed that the repeatedly structural movements maydestroy the reservoir on the one hand, but may extend the interval of hydrocarbon generation on the oth-er hand. The repeatedly sturctural movements is favourable to the hydrocarbon generation of sourcerocks for long time and at various stages.
The thermal history of a single well in Tazhong Area, Tarim basin, was investigated based on the a-petite fission track analysis(AFTA) and spin density of free radicals in kengen, at the same time, the complex evolution of structure and burial history were also studied combining the results of wave-geo-logical analysis. The effect of the complex structural movement to hydrocarbon generation and reservoirformation was discussed. The results of the study revealed that the repeatedly structural movements maydestroy the reservoir on the one hand, but may extend the interval of hydrocarbon generation on the oth-er hand. The repeatedly sturctural movements is favourable to the hydrocarbon generation of sourcerocks for long time and at various stages.
1997, 15(2): 150-154.
Abstract:
The Tazhong A well is the first exploration well to find commercial oil in Silurian strata of theTarim basin. In the article a detaile reservoir geochemistry study was clone to the lower sandstone mem-ber in Silurian strata, so a biref conclusion was made on forming periods of the Silurian pool in theTazhong A well, according to the homogenization temperature of hydrocarbon inclusions and to the tec-tonic evolution and thermal evolution history. There were three periods for hydrocarbon smigration andaccu mu latio noccurred separately in the Silurian一Later Devonian, Inter Permian一Triassic and Hi-malayan period. The largest hydrocarbon accumulationoccurred in the first period, and the widely ds-tributed bitumen sandstone was formed in the end of Devoian, because of the hydrocarbon s oxidationand organism decomposition when whole strata were raised and eroded. The hydrocarbon accumuiatingscale was larger in the second period and there was water washing to a certain degree during the Hi-malayan movement.
The Tazhong A well is the first exploration well to find commercial oil in Silurian strata of theTarim basin. In the article a detaile reservoir geochemistry study was clone to the lower sandstone mem-ber in Silurian strata, so a biref conclusion was made on forming periods of the Silurian pool in theTazhong A well, according to the homogenization temperature of hydrocarbon inclusions and to the tec-tonic evolution and thermal evolution history. There were three periods for hydrocarbon smigration andaccu mu latio noccurred separately in the Silurian一Later Devonian, Inter Permian一Triassic and Hi-malayan period. The largest hydrocarbon accumulationoccurred in the first period, and the widely ds-tributed bitumen sandstone was formed in the end of Devoian, because of the hydrocarbon s oxidationand organism decomposition when whole strata were raised and eroded. The hydrocarbon accumuiatingscale was larger in the second period and there was water washing to a certain degree during the Hi-malayan movement.
1997, 15(2): 160-163.
Abstract:
Aaccording to the study on oil一gas source rocks in China for ten years, at the microscopic and submicroscnpic levels,the authors on the one hand used the microscope photometry together with transmission electronic; microscopya nningelextronic miroscnpy, Fourier transformation infrared microscopy and sexondary ion mass spectrometry to study the petro-logical and geochemical characteristics of organic matter and on the other hand employed small tubes and the pressure cnok-er for thermal simulation, cxmbined with analyses of organic; petrology and geochemistry to elaborate their hydrocarbon-generating regularities. On the basis of these studies, the authors proposed a new classification for sedimentary organicnlatter. This classification is notoy suitable for terrestrial source rocks, but also for marine ones, meanwhile, the influenceof maturity on macec;als is cxmsidered, and the division of source mac;erals was modified. The characteristic of the composition or structure of some macerals such as zoo-organite and amorphonite are deter-mined espeeially the oil-genecating models of both maceraLs in Chinese source rocks and individual marine organisms wereset up.
Aaccording to the study on oil一gas source rocks in China for ten years, at the microscopic and submicroscnpic levels,the authors on the one hand used the microscope photometry together with transmission electronic; microscopya nningelextronic miroscnpy, Fourier transformation infrared microscopy and sexondary ion mass spectrometry to study the petro-logical and geochemical characteristics of organic matter and on the other hand employed small tubes and the pressure cnok-er for thermal simulation, cxmbined with analyses of organic; petrology and geochemistry to elaborate their hydrocarbon-generating regularities. On the basis of these studies, the authors proposed a new classification for sedimentary organicnlatter. This classification is notoy suitable for terrestrial source rocks, but also for marine ones, meanwhile, the influenceof maturity on macec;als is cxmsidered, and the division of source mac;erals was modified. The characteristic of the composition or structure of some macerals such as zoo-organite and amorphonite are deter-mined espeeially the oil-genecating models of both maceraLs in Chinese source rocks and individual marine organisms wereset up.
1997, 15(2): 169-172.
Abstract:
The organic macerals of low maturity source rocks of Es4 in Dongying Depression were classified andquantified by using microscope photometry,and the macerals were cassified into 6 groups as followsinerinite, vitrinite, exinite, sapropelinite, organozooclastinite and secondary group. thdr the property, composition and distribution in different depth and position of this depression. were also studied In ana-lyzing ,it showed that Palaeostomosystis minor is rich especially in some beds, with the common presenceof Botryococcus,Pediastrum sp andBohaidina sp. A direct proportionality exists between mineral itumi-nous groundmass and amorphous substance. In the low mature source rocks from the Domgying Depres-sion, amorphous substance was decomposed by low aquatic organisms and was further determined to beone of the major parent materials of oil and gas. Using the relationship between vitrinite reflectance and conversion efficiency of hydrocarbons and combining the thermal modelling the genesis hydrocarbon-generating and evolution patterns could be well understood from the viewpoint of organic petrology.
The organic macerals of low maturity source rocks of Es4 in Dongying Depression were classified andquantified by using microscope photometry,and the macerals were cassified into 6 groups as followsinerinite, vitrinite, exinite, sapropelinite, organozooclastinite and secondary group. thdr the property, composition and distribution in different depth and position of this depression. were also studied In ana-lyzing ,it showed that Palaeostomosystis minor is rich especially in some beds, with the common presenceof Botryococcus,Pediastrum sp andBohaidina sp. A direct proportionality exists between mineral itumi-nous groundmass and amorphous substance. In the low mature source rocks from the Domgying Depres-sion, amorphous substance was decomposed by low aquatic organisms and was further determined to beone of the major parent materials of oil and gas. Using the relationship between vitrinite reflectance and conversion efficiency of hydrocarbons and combining the thermal modelling the genesis hydrocarbon-generating and evolution patterns could be well understood from the viewpoint of organic petrology.
1997, 15(2): 184-187.
Abstract:
A number of pyrolytic nitrogen com pounds(alkylcarbazoles) were suc cessfully fractionated and de-tected from the Qun-4 well oil of the Tarim basin. And alkylbener carbazoles and alkyldibenzo carbawles, however, were not found in the oil. Of the alkylcarbazoles, dimethylcarbawle,C3一car-bazole and C4一carbazole are dominant with the largest amount for dimethylcarbazole. The other alkyl-carbawle compounds detected are methylcarbazole, C5一carbazole, C6一carbazole, C7一 carbazole and carbazole in the amount order. Several isomers were further identified in methylcarbazoles and dimethyl-carbawles. The amounts of G2 and G3 components are equal in methylcarbazoles, and in dimethylcar-bazoles, G3 is dominated, G2 amount is in the second place and that of G1 is the smallest. The existinganalytical data showed that〔arbazoles are reliable and characterized biomarkers for study of oilmigra-tion. By using the carbazole parameters, it was thought that oils from the Qun-4wellinthe Tarim basinhave undergone a long distance migration.
A number of pyrolytic nitrogen com pounds(alkylcarbazoles) were suc cessfully fractionated and de-tected from the Qun-4 well oil of the Tarim basin. And alkylbener carbazoles and alkyldibenzo carbawles, however, were not found in the oil. Of the alkylcarbazoles, dimethylcarbawle,C3一car-bazole and C4一carbazole are dominant with the largest amount for dimethylcarbazole. The other alkyl-carbawle compounds detected are methylcarbazole, C5一carbazole, C6一carbazole, C7一 carbazole and carbazole in the amount order. Several isomers were further identified in methylcarbazoles and dimethyl-carbawles. The amounts of G2 and G3 components are equal in methylcarbazoles, and in dimethylcar-bazoles, G3 is dominated, G2 amount is in the second place and that of G1 is the smallest. The existinganalytical data showed that〔arbazoles are reliable and characterized biomarkers for study of oilmigra-tion. By using the carbazole parameters, it was thought that oils from the Qun-4wellinthe Tarim basinhave undergone a long distance migration.
1997, 15(2): 192-197.
Abstract:
This paper mainly discussed the effect of some maturity indicators of aromatics prior to and withinthe oil generation zone. By using GC-M S with a modified fused silica capillary column(BPXS) to analysethe extracts of the Yucan-2 well source rock section from the Linqing sag as well as, some source rockand crude oil samples with different maturity in the Shengli oilliekl. In present study, the distribution characteristics of aromatics in chromatograms, the ratio of perylene and benzoflouranthene vs. benzo(e)py rene, β Η deydroxyto一copherol ratio, 2, 6+ 2, 7/1,5 dimethylnaphthalene ratio and dehydroxyt copherol are some reliable markers of low maturity. A combination of maturity indicators from 2, 3, 6/2,3, 6+ 1, 2, 5 trimethyl-raphthalene ratio and 1, 3, 6, 7/1, 3, 6, 7+ 1, 2, 5, 6 tetramethylnaph thalene ratio i suseful for the assessmnt of crude oils and source rocks in the whop thermal evolution zone.
This paper mainly discussed the effect of some maturity indicators of aromatics prior to and withinthe oil generation zone. By using GC-M S with a modified fused silica capillary column(BPXS) to analysethe extracts of the Yucan-2 well source rock section from the Linqing sag as well as, some source rockand crude oil samples with different maturity in the Shengli oilliekl. In present study, the distribution characteristics of aromatics in chromatograms, the ratio of perylene and benzoflouranthene vs. benzo(e)py rene, β Η deydroxyto一copherol ratio, 2, 6+ 2, 7/1,5 dimethylnaphthalene ratio and dehydroxyt copherol are some reliable markers of low maturity. A combination of maturity indicators from 2, 3, 6/2,3, 6+ 1, 2, 5 trimethyl-raphthalene ratio and 1, 3, 6, 7/1, 3, 6, 7+ 1, 2, 5, 6 tetramethylnaph thalene ratio i suseful for the assessmnt of crude oils and source rocks in the whop thermal evolution zone.
1997, 15(2): 207-211.
Abstract:
The genetic classification of crude oils and oil/source correlation were studied based on the deposi-tional environment and the input of parent materials of crude oils and source rocks from the Turpan-Ha-mi Basin by the research of the distribution and assemblage characteristics of biomarkers and stable car-bon isotope compositions and distribution model of individual hydrocarbons, which were detectedthrough the gas chromatographzsotope ratio in mass spectrometer the following three aspects 1)thetypical lacustrine-wamp or swamp fades coal-derived oil, such as crude oils gencrated from the Jurassicof Taibei Depression; 2) the lacustrine oils, like the Triassic oil from the Tuocan 1 well; 3) the shallowlylacustrine oil, such as the Middle Jurassic oil in the Shengjingkou oilfield. Theensups of oil /source corenlation showed that the Jurassic oils in Taibei Depression is originated from the Middle-Lower Jurassic coal measure organic matter,and the Triassic oil in the Tuokexun Depression is from Upper Permian la-custrine fades mud stones in the Turpan-HamiBasin.
The genetic classification of crude oils and oil/source correlation were studied based on the deposi-tional environment and the input of parent materials of crude oils and source rocks from the Turpan-Ha-mi Basin by the research of the distribution and assemblage characteristics of biomarkers and stable car-bon isotope compositions and distribution model of individual hydrocarbons, which were detectedthrough the gas chromatographzsotope ratio in mass spectrometer the following three aspects 1)thetypical lacustrine-wamp or swamp fades coal-derived oil, such as crude oils gencrated from the Jurassicof Taibei Depression; 2) the lacustrine oils, like the Triassic oil from the Tuocan 1 well; 3) the shallowlylacustrine oil, such as the Middle Jurassic oil in the Shengjingkou oilfield. Theensups of oil /source corenlation showed that the Jurassic oils in Taibei Depression is originated from the Middle-Lower Jurassic coal measure organic matter,and the Triassic oil in the Tuokexun Depression is from Upper Permian la-custrine fades mud stones in the Turpan-HamiBasin.
1997, 15(2): 216-219.
Abstract:
High content of H2S exists universally in the natural gas in Sichuan Basin. The authors collectednearly 120 gas samples of different geological times from Sichuan and analysed their H2S contents,and inpart of the samples, the sulphur isotopic composition of hydrogen sulphides was also determined. Therelationship between the Hz S concentration,its sulphur isotopic composition in natural gases and the sed-imentary geochemical facies were discussed by combining with theH2S content data of the other oil-andgas-bearing besins in China. The results showed that high H2 conntrantion and heavy Saoncentrantions and heavy δ34S clueshave a formative relation with the distribution of carbonate rocks and evaporite rocks, while the naturalgases generated incal fo rmatio n,ccastic rocks or non-carbonate marine sedimentary stratum have a lowH2S oncentration and lighter δ34S value. Accordingly, the source and sedimentary environment of nat-ural gases were discussed in this paper by means of the〔haracteristics of the sulphur isotope of hydrogens ulphi de s.
High content of H2S exists universally in the natural gas in Sichuan Basin. The authors collectednearly 120 gas samples of different geological times from Sichuan and analysed their H2S contents,and inpart of the samples, the sulphur isotopic composition of hydrogen sulphides was also determined. Therelationship between the Hz S concentration,its sulphur isotopic composition in natural gases and the sed-imentary geochemical facies were discussed by combining with theH2S content data of the other oil-andgas-bearing besins in China. The results showed that high H2 conntrantion and heavy Saoncentrantions and heavy δ34S clueshave a formative relation with the distribution of carbonate rocks and evaporite rocks, while the naturalgases generated incal fo rmatio n,ccastic rocks or non-carbonate marine sedimentary stratum have a lowH2S oncentration and lighter δ34S value. Accordingly, the source and sedimentary environment of nat-ural gases were discussed in this paper by means of the〔haracteristics of the sulphur isotope of hydrogens ulphi de s.
1997, 15(2): 226-231.
Abstract:
The role of organic matter in the formation of strata-bound Pb-Zn deposits was discussed widely.The experimental studies in this paper included three aspects as follow:1. The partition coefficients of Pb2+ and Zn2+between、oexisting liquid oil and aqueous phase weredetermined in aqueous solutions with various pH and composition. The results suggested that Cu, Pb, andZn ahow a strong tendency to enrich liquid oil in alkaline aqueous solution, and that in acid conditionthese elements were still enriched in aqueous solution phase. 2. The solubilities of sphalerite and galena in oilfield brine and CaCl2-NaCl solution, which had thesame salinities as the brine, were determined, respectively. Furthermore, the competitive abilities of metalelements betty een o rgani c a nd ino rganic com posi do ns in oilfi eld brine w ere di scus sed. 3. Based on the hypothesis of double source rocks, the relationship between formation and primarymigration of oil and mobilization of lead and zinc were studies experimentally. The results showed thatth e concentration of Zn in chloroform extractsmetal elements were obtained in migrated oil asup to 52一691u-g/g and that higher concentrations ofTherefore, it was reasonably suggested that liquid oil is an important carrier of metal elements andimportant composition of ore-forming fluid at appropriate maturity limit of oil evolution.
The role of organic matter in the formation of strata-bound Pb-Zn deposits was discussed widely.The experimental studies in this paper included three aspects as follow:1. The partition coefficients of Pb2+ and Zn2+between、oexisting liquid oil and aqueous phase weredetermined in aqueous solutions with various pH and composition. The results suggested that Cu, Pb, andZn ahow a strong tendency to enrich liquid oil in alkaline aqueous solution, and that in acid conditionthese elements were still enriched in aqueous solution phase. 2. The solubilities of sphalerite and galena in oilfield brine and CaCl2-NaCl solution, which had thesame salinities as the brine, were determined, respectively. Furthermore, the competitive abilities of metalelements betty een o rgani c a nd ino rganic com posi do ns in oilfi eld brine w ere di scus sed. 3. Based on the hypothesis of double source rocks, the relationship between formation and primarymigration of oil and mobilization of lead and zinc were studies experimentally. The results showed thatth e concentration of Zn in chloroform extractsmetal elements were obtained in migrated oil asup to 52一691u-g/g and that higher concentrations ofTherefore, it was reasonably suggested that liquid oil is an important carrier of metal elements andimportant composition of ore-forming fluid at appropriate maturity limit of oil evolution.
1997, 15(2): 236-240.
Abstract:
Physical, chemical and biologiocal reactions occur in the process of the oil pollution in groundwater.By using the oil pollution moitoring data of a drinking groundwater source in Zibo City,East of China,the hydrogeochemical change and the relation between total oil concentration and the other componentsin ground waterwere studied for the first time. Someground water environmental background values weresuggested to be the important hydrogeochemical indices of the oil pollution in groundwater. The moreserious the pollution of groundwate, the greater magrritude the increase Cl-,CO D, hardness and TDS.Oppositely,the lower the oil content of groundwater, the higher the level of NO3The hydrogeochenical change is resulted by hydrogeochmical reactions such as ionic exchtinge, nitration and countergi-nitrati on.
Physical, chemical and biologiocal reactions occur in the process of the oil pollution in groundwater.By using the oil pollution moitoring data of a drinking groundwater source in Zibo City,East of China,the hydrogeochemical change and the relation between total oil concentration and the other componentsin ground waterwere studied for the first time. Someground water environmental background values weresuggested to be the important hydrogeochemical indices of the oil pollution in groundwater. The moreserious the pollution of groundwate, the greater magrritude the increase Cl-,CO D, hardness and TDS.Oppositely,the lower the oil content of groundwater, the higher the level of NO3The hydrogeochenical change is resulted by hydrogeochmical reactions such as ionic exchtinge, nitration and countergi-nitrati on.
