The managing of information and data between researching groups is critical to the success of any exploration or development project. Poor communication and data sharing between technological departments can result in...The managing of information and data between researching groups is critical to the success of any exploration or development project. Poor communication and data sharing between technological departments can result in incomplete interpretations or inaccurate drilling decisions making. According to the statistic results, the time cost in retrieving and collecting data will occupy more than 70 % percent of the total working time of technicians during the petroleum geological researching. This paper is a summary of the characteristics and the development of the Data & Graphic management system for oil & gas exploration.After that the system's application in oil & gas exploration and researching, which has improved the quality and accurateness of mapping has been summarized in detail. The application of the system mentioned above has proved to be very successful in Daqing oilfield.展开更多
Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir ...Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper.展开更多
A growing body of evidence shows that volcanism near the Permian-Triassic boundary（PTB） may be crucial in triggering the Permian–Triassic（P–Tr） mass extinction. Thus, the ash beds near the PTB in South China may...A growing body of evidence shows that volcanism near the Permian-Triassic boundary（PTB） may be crucial in triggering the Permian–Triassic（P–Tr） mass extinction. Thus, the ash beds near the PTB in South China may carry information on this event. Three volcanic ash layers, altered to clay, outcropped in the PTB beds in Zunyi Section, Guizhou Province, Southwest China. The U-Pb ages, trace elements, and Hf-isotope compositions of zircon grains from these three ash beds were analyzed using LA-ICPMS and LA-MC-ICPMS. The zircons are mainly magmatic in origin（241-279 Ma） except for two inherited/xenocrystic zircons（939 and 2 325 Ma）. The ages of these magmatic zircons indicate three episodes of magmatism which occurred around the MiddleLate Permian boundary（-261.5 Ma, MLPB）, the Wuchiapingian-Changhsingian boundary（-254.5 Ma, WCB）, and the PTB（-250.5 Ma）, respectively. The first two episodes of magmatism near the MLPB and WCB may be attributed to magmatic inheritance or re-deposition. All magmatic zircons share similar trace-element and Hf-isotope compositions. They have Y, Hf, Th and U contents and Nb/Ta ratios are typical of zircons from silicic calc-alkaline magmas. These zircons also exhibit enriched Hf-isotope compositions with _（εHf）（t） values of-11.4 to ＋0.2, which suggests that the three magmatic episodes involved melting of the continental crust. The more enriched Hf-isotope composition （_（εHf）（t）=-11.4--4.8） of Bed ZY13（-250.5 Ma） implies more input of ancient crustal material in the magma. Integration of the Hf-isotope and trace-element compositions of magmatic zircons suggest that these three episodes of magmatism may take place along the convergent continent margin in or near southwestern South China as a result of the closure of the Palaeo-Tethys Ocean.展开更多
The characteristics of ultralow permeability reservoirs changed after waterflooding. Thin- section analysis and scanning electron microscopy （SEM） of core samples from inspection wells indicated that calcite and bar...The characteristics of ultralow permeability reservoirs changed after waterflooding. Thin- section analysis and scanning electron microscopy （SEM） of core samples from inspection wells indicated that calcite and barite were formed in ultralow permeability reservoirs during waterflooding operations. Some asphaltene precipitates on the surface of formation rock would influence the reservoir porosity, permeability, wettability, and electrical properties. In this paper, the changes of physical, electrical, and fluid properties of ultralow permeability reservoirs during waterflooding operations were analyzed. This provides important information to improve waterflooding performance in ultralow permeability reservoirs.展开更多
During several decades of exploration, a number of mantle-derived natural gas pools have been discovered in the vicinities of deep faults in the Songliao Basin, northeastern China. The natural gas in these pools has a...During several decades of exploration, a number of mantle-derived natural gas pools have been discovered in the vicinities of deep faults in the Songliao Basin, northeastern China. The natural gas in these pools has a δ13C1 value of ?16.50/00 to ?24.20/00, a reversed arrangement in the amount of carbon isotopes in methane and its endogamous products (namely, δ13C1 >δ13C2 >δ13C3 >δ13C4), a 3He/4He value of 1.97 to 2.34×10-6,and an Ar/36Ar value of 1063 to 1949. This indicates a mantle 40 source for the natural gas. The trace elements Cd, In, Te and Re, never found in organic-sourced hydrocarbons, are highly enriched in certain crude oils from the Basin; respectively, concentrations of these elements were found to be 751, 28, 16 and 323 times the average crustal values in China, and this also supports a mantle-derived natural gas origin. The characteristics of mantled-derived magmatic rocks, hydrothermal fluids and gaseous fractions distributed in and near the deep Songliao Basin faults indicate that rifting tectonics is providing the mechanisms for this outgassing of the mantle. Deep extensional (normal) faults provide pathways for upward movement of these materials, and in the Songliao Basin, these deep rift fault zones are associated with reservoir occurrence and cap rock seals, forming good sites for accumulation of mantle-derived natural gas. Furthermore, a layer of low velocity, low density and high conductivity in the deep crust has been identified as a potential reservoir for mantle-derived natural gas.展开更多
1 Introduction The Lower Silurian Longmaxl Formation is the most prolific shale gas producing unit in the Sichuan Basin by the large thickness and rich resources, which also indicate a bright exploration prospect for ...1 Introduction The Lower Silurian Longmaxl Formation is the most prolific shale gas producing unit in the Sichuan Basin by the large thickness and rich resources, which also indicate a bright exploration prospect for the unconventional shale gas.展开更多
1 Introduction The importance of the unconventional petroleum is increasingly prominent, with the rising demand of oil and gas in the economic and social development and the gradual consumption and depletion of conven...1 Introduction The importance of the unconventional petroleum is increasingly prominent, with the rising demand of oil and gas in the economic and social development and the gradual consumption and depletion of conventional oil and gas resources. Compared with the shale and coal-bed gas reservoir, tight reservoir has better fracturing capability.展开更多
CO2 flooding is a process whereby carbon dioxide is injected into an oil reservoir in order to increase output when extracting oil. Since 1952, Wharton obtained the patent concern CO2 flooding, CO2-EOR （CO2 flooding ...CO2 flooding is a process whereby carbon dioxide is injected into an oil reservoir in order to increase output when extracting oil. Since 1952, Wharton obtained the patent concern CO2 flooding, CO2-EOR （CO2 flooding enhance oil recovery） has been one of research hot-spot around the world. According to the statistical data of 2006, there are total of 94 global CO2-EOR projects, including 65 low permeability oilfield projects （79% of the total）. Daqing Oilfield is the largest one of China, after more than 50 years of continuous development, oilfield comprehensive water cut has reached over 90%, and the difficulty of oilfield development has been gradually increasing. In recent years, low and ultra-low permeability reservoirs development have played a more and more important role accompany with low permeability reserves in proportion of the total reserves have been increasing year by year. But water-flooding recovery of low permeability reservoir is very low under the influence of reservoir poor properties and heterogeneity. As a kind of greenhouse gas, CO2 flooding can obtain good results for the low permeability reservoir in which the water flooding has proven ineffective. CO2 flooding Pilot Test was conducted under such background since Dec. 2002, over 10 years of practice has proved that CO2 flooding is an effective method to improve the development effect of low permeability reservoir, all experience during the mechanism study and field test should present important references for further larger-scale CO2 flooding projects.展开更多
A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of D...A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of Daning coal mine in Jincheng, Shanxi Province. The gas production rate and pressure change at both ends of the sample were studied systematically, and the mechanisms of some phenomena in the experiment were discussed. The experimental results show that, whether at fast or slow depressurizing rate, the methane adsorbed to high-rank coal can effectively desorb and the desorption efficiency can reach above 90%. There is an obvious inflection point on the gas yield curve during the desorption process and it appears after the pressure on the lump of coal reduces below the desorption pressure. The desorption of methane from high-rank coal is mainly driven by differential pressure, and high pressure difference is conducive to fast desorption. In the scenario of fast depressurization, the desorption inflection appears earlier and the gas production rate in the stage of rapid desorption is higher. It is experimentally concluded that the originally recognized strategy of long-term slow CBM production is doubtful and the economic benefit of CBM exploitation from high-rank coal can be effectively improved by rapid drainage and pressure reduction. The field experiment results in pilot blocks of Fanzhuang and Zhengzhuang show that by increasing the drainage depressurization rate, the peak production of gas well would increase greatly, the time of gas well to reach the economic production shortened, the average time for a gas well to reach expected production reduced by half, and the peak gas production is higher.展开更多
Ankangite is a new mineral containing Ba, Ti and V. It was named after the discovery of locality, Ankang County, Shaanxi Province. Ankangite has been approved by the Commission on New Minerals and Mineral Names of the...Ankangite is a new mineral containing Ba, Ti and V. It was named after the discovery of locality, Ankang County, Shaanxi Province. Ankangite has been approved by the Commission on New Minerals and Mineral Names of the I. M. A.展开更多
文摘The managing of information and data between researching groups is critical to the success of any exploration or development project. Poor communication and data sharing between technological departments can result in incomplete interpretations or inaccurate drilling decisions making. According to the statistic results, the time cost in retrieving and collecting data will occupy more than 70 % percent of the total working time of technicians during the petroleum geological researching. This paper is a summary of the characteristics and the development of the Data & Graphic management system for oil & gas exploration.After that the system's application in oil & gas exploration and researching, which has improved the quality and accurateness of mapping has been summarized in detail. The application of the system mentioned above has proved to be very successful in Daqing oilfield.
基金This project is the applied fundamental research projects (04A10101) sponsored by the scientific and technology developmentdepartment of CNPC.
文摘Carbonate karst reservoir is the emphases of Tarim＇s carbonate exploration. However, it is buried at a large depth, which results in Weak seismic reflection signal and low S/N ratio. In addition, the karst reservoir contains great heterogeneity, so reservoir prediction is very difficult. Through many years of research and exploration, we have established a suite of comprehensive evaluation technology for carbonate karst reservoir using geophysical characteristics and a geological concept model, including a technique for reconstructing the paleogeomorphology of buried hills based on a sequence framework, seismic description of the karst reservoir, and strain variant analysis for fracture estimation. The evaluation technology has been successfully applied in the Tabei and Tazhong areas, and commercial production of oil and gas has been achieved. We show the application of this technology in the Lunguxi area in North Tarim in this paper.
基金supported by an aid grant from Chengdu Center, China Geological Survey (No. 12120113049100-1)the National Natural Science Foundations (Nos. 40572068, 40839903 and 41272044)+1 种基金the "111" Program (No. B08030)an aid grant (No. GBL11206) from the State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), China
文摘A growing body of evidence shows that volcanism near the Permian-Triassic boundary（PTB） may be crucial in triggering the Permian–Triassic（P–Tr） mass extinction. Thus, the ash beds near the PTB in South China may carry information on this event. Three volcanic ash layers, altered to clay, outcropped in the PTB beds in Zunyi Section, Guizhou Province, Southwest China. The U-Pb ages, trace elements, and Hf-isotope compositions of zircon grains from these three ash beds were analyzed using LA-ICPMS and LA-MC-ICPMS. The zircons are mainly magmatic in origin（241-279 Ma） except for two inherited/xenocrystic zircons（939 and 2 325 Ma）. The ages of these magmatic zircons indicate three episodes of magmatism which occurred around the MiddleLate Permian boundary（-261.5 Ma, MLPB）, the Wuchiapingian-Changhsingian boundary（-254.5 Ma, WCB）, and the PTB（-250.5 Ma）, respectively. The first two episodes of magmatism near the MLPB and WCB may be attributed to magmatic inheritance or re-deposition. All magmatic zircons share similar trace-element and Hf-isotope compositions. They have Y, Hf, Th and U contents and Nb/Ta ratios are typical of zircons from silicic calc-alkaline magmas. These zircons also exhibit enriched Hf-isotope compositions with _（εHf）（t） values of-11.4 to ＋0.2, which suggests that the three magmatic episodes involved melting of the continental crust. The more enriched Hf-isotope composition （_（εHf）（t）=-11.4--4.8） of Bed ZY13（-250.5 Ma） implies more input of ancient crustal material in the magma. Integration of the Hf-isotope and trace-element compositions of magmatic zircons suggest that these three episodes of magmatism may take place along the convergent continent margin in or near southwestern South China as a result of the closure of the Palaeo-Tethys Ocean.
基金the financial support from the major science and technology project of Petrochina(Key Technology Study of Stable Production and Enhanced Oil Recovery in the Changqing Oil field.No.2011E-1305)
文摘The characteristics of ultralow permeability reservoirs changed after waterflooding. Thin- section analysis and scanning electron microscopy （SEM） of core samples from inspection wells indicated that calcite and barite were formed in ultralow permeability reservoirs during waterflooding operations. Some asphaltene precipitates on the surface of formation rock would influence the reservoir porosity, permeability, wettability, and electrical properties. In this paper, the changes of physical, electrical, and fluid properties of ultralow permeability reservoirs during waterflooding operations were analyzed. This provides important information to improve waterflooding performance in ultralow permeability reservoirs.
文摘During several decades of exploration, a number of mantle-derived natural gas pools have been discovered in the vicinities of deep faults in the Songliao Basin, northeastern China. The natural gas in these pools has a δ13C1 value of ?16.50/00 to ?24.20/00, a reversed arrangement in the amount of carbon isotopes in methane and its endogamous products (namely, δ13C1 >δ13C2 >δ13C3 >δ13C4), a 3He/4He value of 1.97 to 2.34×10-6,and an Ar/36Ar value of 1063 to 1949. This indicates a mantle 40 source for the natural gas. The trace elements Cd, In, Te and Re, never found in organic-sourced hydrocarbons, are highly enriched in certain crude oils from the Basin; respectively, concentrations of these elements were found to be 751, 28, 16 and 323 times the average crustal values in China, and this also supports a mantle-derived natural gas origin. The characteristics of mantled-derived magmatic rocks, hydrothermal fluids and gaseous fractions distributed in and near the deep Songliao Basin faults indicate that rifting tectonics is providing the mechanisms for this outgassing of the mantle. Deep extensional (normal) faults provide pathways for upward movement of these materials, and in the Songliao Basin, these deep rift fault zones are associated with reservoir occurrence and cap rock seals, forming good sites for accumulation of mantle-derived natural gas. Furthermore, a layer of low velocity, low density and high conductivity in the deep crust has been identified as a potential reservoir for mantle-derived natural gas.
文摘1 Introduction The Lower Silurian Longmaxl Formation is the most prolific shale gas producing unit in the Sichuan Basin by the large thickness and rich resources, which also indicate a bright exploration prospect for the unconventional shale gas.
文摘1 Introduction The importance of the unconventional petroleum is increasingly prominent, with the rising demand of oil and gas in the economic and social development and the gradual consumption and depletion of conventional oil and gas resources. Compared with the shale and coal-bed gas reservoir, tight reservoir has better fracturing capability.
文摘CO2 flooding is a process whereby carbon dioxide is injected into an oil reservoir in order to increase output when extracting oil. Since 1952, Wharton obtained the patent concern CO2 flooding, CO2-EOR （CO2 flooding enhance oil recovery） has been one of research hot-spot around the world. According to the statistical data of 2006, there are total of 94 global CO2-EOR projects, including 65 low permeability oilfield projects （79% of the total）. Daqing Oilfield is the largest one of China, after more than 50 years of continuous development, oilfield comprehensive water cut has reached over 90%, and the difficulty of oilfield development has been gradually increasing. In recent years, low and ultra-low permeability reservoirs development have played a more and more important role accompany with low permeability reserves in proportion of the total reserves have been increasing year by year. But water-flooding recovery of low permeability reservoir is very low under the influence of reservoir poor properties and heterogeneity. As a kind of greenhouse gas, CO2 flooding can obtain good results for the low permeability reservoir in which the water flooding has proven ineffective. CO2 flooding Pilot Test was conducted under such background since Dec. 2002, over 10 years of practice has proved that CO2 flooding is an effective method to improve the development effect of low permeability reservoir, all experience during the mechanism study and field test should present important references for further larger-scale CO2 flooding projects.
基金Supported by the China National Science and Technology Major Project(2017ZX05064)
文摘A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of Daning coal mine in Jincheng, Shanxi Province. The gas production rate and pressure change at both ends of the sample were studied systematically, and the mechanisms of some phenomena in the experiment were discussed. The experimental results show that, whether at fast or slow depressurizing rate, the methane adsorbed to high-rank coal can effectively desorb and the desorption efficiency can reach above 90%. There is an obvious inflection point on the gas yield curve during the desorption process and it appears after the pressure on the lump of coal reduces below the desorption pressure. The desorption of methane from high-rank coal is mainly driven by differential pressure, and high pressure difference is conducive to fast desorption. In the scenario of fast depressurization, the desorption inflection appears earlier and the gas production rate in the stage of rapid desorption is higher. It is experimentally concluded that the originally recognized strategy of long-term slow CBM production is doubtful and the economic benefit of CBM exploitation from high-rank coal can be effectively improved by rapid drainage and pressure reduction. The field experiment results in pilot blocks of Fanzhuang and Zhengzhuang show that by increasing the drainage depressurization rate, the peak production of gas well would increase greatly, the time of gas well to reach the economic production shortened, the average time for a gas well to reach expected production reduced by half, and the peak gas production is higher.
文摘Ankangite is a new mineral containing Ba, Ti and V. It was named after the discovery of locality, Ankang County, Shaanxi Province. Ankangite has been approved by the Commission on New Minerals and Mineral Names of the I. M. A.
