Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil env...Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.展开更多
On December 2, 2017, the 2nd Seminar on the Development Strategy of China＇s Oil and Gas Resources was held in Beijing. This seminar was hosted by the Strategic Research Center for Oil and Gas Resources, Ministry of L...On December 2, 2017, the 2nd Seminar on the Development Strategy of China＇s Oil and Gas Resources was held in Beijing. This seminar was hosted by the Strategic Research Center for Oil and Gas Resources, Ministry of Land （MLR） and Resources and sponsored by both the CNOOC Exploration Department and the School of Ocean and Earth Sciences of Tongji University. With the theme of ＂deepwater and deep-layer oil and gas resources and development strategy＂,展开更多
We present the first successful application of three-component seismic data to thin interbedded reservoir characterization in the Daqing placanticline of the LMD oilfield. The oilfield has reached the final high water...We present the first successful application of three-component seismic data to thin interbedded reservoir characterization in the Daqing placanticline of the LMD oilfield. The oilfield has reached the final high water cut stage and the principal problem is how to recognize the boundaries of sand layers that are thicker than 2 m. Conventional interpretation of single PP-wave seismic data results in multiple solutions, whereas the introduction of PS-wave enhances the reliability of interpretation. We analyze the gas reservoir characteristics by joint PP- and PS-waves, and use the amplitude and frequency decomposition attributes to delineate the gas reservoir boundaries because of the minimal effect of fl uids on S-wave. We perform joint inversion of PP- and PS-waves to obtain V P/V S, λρ, and μρ and map the lithology changes by using density, λρ, and μρ. The 3D–3C attribute λρ slices describe the sand layers distribution, while considering the well log data, and point to favorable region for tapping the remaining oil.展开更多
Shenhu Area is located in the Baiyun Sag of Pearl River Mouth Basin,which is on the northern continental slope of the South China Sea.Gas hydrates in this area have been intensively investigated,achieving a wide cover...Shenhu Area is located in the Baiyun Sag of Pearl River Mouth Basin,which is on the northern continental slope of the South China Sea.Gas hydrates in this area have been intensively investigated,achieving a wide coverage of the three-dimensional seismic survey,a large number of boreholes,and detailed data of the seismic survey,logging,and core analysis.In the beginning of 2020,China has successfully conducted the second offshore production test of gas hydrates in this area.In this paper,studies were made on the structure of the hydrate system for the production test,based on detailed logging data and core analysis of this area.As to the results of nuclear magnetic resonance(NMR)logging and sonic logging of Well GMGS6-SH02 drilled during the GMGS6 Expedition,the hydrate system on which the production well located can be divided into three layers:(1)207.8–253.4 mbsf,45.6 m thick,gas hydrate layer,with gas hydrate saturation of 0–54.5%(31%av.);(2)253.4–278 mbsf,24.6 m thick,mixing layer consisting of gas hydrates,free gas,and water,with gas hydrate saturation of 0–22%(10%av.)and free gas saturation of 0–32%(13%av.);(3)278–297 mbsf,19 m thick,with free gas saturation of less than 7%.Moreover,the pore water freshening identified in the sediment cores,taken from the depth below the theoretically calculated base of methane hydrate stability zone,indicates the occurrence of gas hydrate.All these data reveal that gas hydrates,free gas,and water coexist in the mixing layer from different aspects.展开更多
The upper tertiary to quaternary is the main target layer for oil and gas exploitation in China's Mainland, especially crude oil production in the Bohai Basin accounts for approximately 40% of China’s crude oil p...The upper tertiary to quaternary is the main target layer for oil and gas exploitation in China's Mainland, especially crude oil production in the Bohai Basin accounts for approximately 40% of China’s crude oil production. Therefore, a study of the Upper Tertiary to Quaternary has important significance for science and practical applications. In this study, using the receiver function method, Ps and later phase extraction, the sedimentary thickness and an accurate estimate of velocity ratio can be obtained. The technique is simple, its calculation results are unique, and it can be applied to a study of the sedimentary layer. The technique is promising for oil and gas exploration.展开更多
基金supported by the National Science Foundation of China(Grant numbers 52274062)Natural Science Foundation of Liaoning Province(Grant numbers 2022-MS-362)。
文摘Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.
文摘On December 2, 2017, the 2nd Seminar on the Development Strategy of China＇s Oil and Gas Resources was held in Beijing. This seminar was hosted by the Strategic Research Center for Oil and Gas Resources, Ministry of Land （MLR） and Resources and sponsored by both the CNOOC Exploration Department and the School of Ocean and Earth Sciences of Tongji University. With the theme of ＂deepwater and deep-layer oil and gas resources and development strategy＂,
基金sponsored by the China Postdoctoral Science Foundation Projects(2014M550779)
文摘We present the first successful application of three-component seismic data to thin interbedded reservoir characterization in the Daqing placanticline of the LMD oilfield. The oilfield has reached the final high water cut stage and the principal problem is how to recognize the boundaries of sand layers that are thicker than 2 m. Conventional interpretation of single PP-wave seismic data results in multiple solutions, whereas the introduction of PS-wave enhances the reliability of interpretation. We analyze the gas reservoir characteristics by joint PP- and PS-waves, and use the amplitude and frequency decomposition attributes to delineate the gas reservoir boundaries because of the minimal effect of fl uids on S-wave. We perform joint inversion of PP- and PS-waves to obtain V P/V S, λρ, and μρ and map the lithology changes by using density, λρ, and μρ. The 3D–3C attribute λρ slices describe the sand layers distribution, while considering the well log data, and point to favorable region for tapping the remaining oil.
基金Jointly funded by a major research plan of National Natural Science Foundation of China(51991365)titled“Multi-Field Spatial-Temporal Evolution Laws of Phase Transition and Seepage of Natural Gas Hydrate in Reservoirs”and a geological survey project initiated by China Geological Survey(DD20190226)titled“Implementation of Natural Gas Hydrate Production Test in Pilot Test Area in Shenhu Area”.
文摘Shenhu Area is located in the Baiyun Sag of Pearl River Mouth Basin,which is on the northern continental slope of the South China Sea.Gas hydrates in this area have been intensively investigated,achieving a wide coverage of the three-dimensional seismic survey,a large number of boreholes,and detailed data of the seismic survey,logging,and core analysis.In the beginning of 2020,China has successfully conducted the second offshore production test of gas hydrates in this area.In this paper,studies were made on the structure of the hydrate system for the production test,based on detailed logging data and core analysis of this area.As to the results of nuclear magnetic resonance(NMR)logging and sonic logging of Well GMGS6-SH02 drilled during the GMGS6 Expedition,the hydrate system on which the production well located can be divided into three layers:(1)207.8–253.4 mbsf,45.6 m thick,gas hydrate layer,with gas hydrate saturation of 0–54.5%(31%av.);(2)253.4–278 mbsf,24.6 m thick,mixing layer consisting of gas hydrates,free gas,and water,with gas hydrate saturation of 0–22%(10%av.)and free gas saturation of 0–32%(13%av.);(3)278–297 mbsf,19 m thick,with free gas saturation of less than 7%.Moreover,the pore water freshening identified in the sediment cores,taken from the depth below the theoretically calculated base of methane hydrate stability zone,indicates the occurrence of gas hydrate.All these data reveal that gas hydrates,free gas,and water coexist in the mixing layer from different aspects.
文摘The upper tertiary to quaternary is the main target layer for oil and gas exploitation in China's Mainland, especially crude oil production in the Bohai Basin accounts for approximately 40% of China’s crude oil production. Therefore, a study of the Upper Tertiary to Quaternary has important significance for science and practical applications. In this study, using the receiver function method, Ps and later phase extraction, the sedimentary thickness and an accurate estimate of velocity ratio can be obtained. The technique is simple, its calculation results are unique, and it can be applied to a study of the sedimentary layer. The technique is promising for oil and gas exploration.
