Microseismic phase detection and arrival picking are critical steps in the processing of hydraulic fracturing microseismic monitoring data.As the signal-to-noise ratios of P-and S-waves diff er because of the infl uen...Microseismic phase detection and arrival picking are critical steps in the processing of hydraulic fracturing microseismic monitoring data.As the signal-to-noise ratios of P-and S-waves diff er because of the infl uence of focal mechanisms,geometry,and background noise,diffi culties are introduced in the eff ective discrimination of seismic phases and the accurate acquisition of arrivals in conventional processing methods.In this paper,we propose a method for identifying microseismic phase arrival time by comprehensively analyzing the variation of moveout curves and combining the intra-event waveform similarities with the energy ratio of multitrace signals.First,a curve-fi tting formula is constructed with perforation arrivals,and event detection is achieved by adopting an energy-weighted similarity coeffi cient that seeks plausible fi tting curves with a sliding time window in continuous microseismic recordings.Then,the P-and S-waves are separated by the fitting parameters.The known arrival time trend of the microseismic phase is employed to calculate residual time corrections.Finally,the accurate arrival results of the microseismic phases can be obtained by picking the arrivals of stacked traces.The reliability and eff ectiveness of the proposed method for microseismic phase detection and arrival picking were determined through tests using field data.Arrival results indicate that the proposed method can improve accuracy compared with the traditional energy ratio method.展开更多
One new mixed-valence heptanuclear manganese complex, [Mn^ⅡMn^Ⅲ6O2L6-(NaCH3COO)2(CH3COO)4](1)(L = 3-ethoxy-6-((2-hydroxyethyl)imino)methyl) phenol, was synthesized by treating the Schiff-base ligand with Mn(acac)3&#...One new mixed-valence heptanuclear manganese complex, [Mn^ⅡMn^Ⅲ6O2L6-(NaCH3COO)2(CH3COO)4](1)(L = 3-ethoxy-6-((2-hydroxyethyl)imino)methyl) phenol, was synthesized by treating the Schiff-base ligand with Mn(acac)3·4H2O and characterized by elemental analysis, IR spectra, thermogravimetric analyses and X-ray single-crystal diffraction. 1 has a similar new mixed-valence heptanuclear structure. The magnetic measurements indicate that 1 exhibits the antiferromagnetic interactions.展开更多
基金This work has been funded by the National Key Research and Development Project(2017YFC0307605,2017YFC0307702),National Science and Technology Major Project of China(No.2017ZX05008-008)and State Key Project(2016ZX05051004).The authors also thank Sinopec Oilfield Service Jianghan Corporation for providing the data and support and express their gratitude to the reviewers for their constructive comments.
文摘Microseismic phase detection and arrival picking are critical steps in the processing of hydraulic fracturing microseismic monitoring data.As the signal-to-noise ratios of P-and S-waves diff er because of the infl uence of focal mechanisms,geometry,and background noise,diffi culties are introduced in the eff ective discrimination of seismic phases and the accurate acquisition of arrivals in conventional processing methods.In this paper,we propose a method for identifying microseismic phase arrival time by comprehensively analyzing the variation of moveout curves and combining the intra-event waveform similarities with the energy ratio of multitrace signals.First,a curve-fi tting formula is constructed with perforation arrivals,and event detection is achieved by adopting an energy-weighted similarity coeffi cient that seeks plausible fi tting curves with a sliding time window in continuous microseismic recordings.Then,the P-and S-waves are separated by the fitting parameters.The known arrival time trend of the microseismic phase is employed to calculate residual time corrections.Finally,the accurate arrival results of the microseismic phases can be obtained by picking the arrivals of stacked traces.The reliability and eff ectiveness of the proposed method for microseismic phase detection and arrival picking were determined through tests using field data.Arrival results indicate that the proposed method can improve accuracy compared with the traditional energy ratio method.
基金financially supported by the Key Scientic Research Projects of Colleges and Universities,Henan Province(No.18A150020)Anyang Key Laboratory for Chemical Biosensing(No.21302003)
文摘One new mixed-valence heptanuclear manganese complex, [Mn^ⅡMn^Ⅲ6O2L6-(NaCH3COO)2(CH3COO)4](1)(L = 3-ethoxy-6-((2-hydroxyethyl)imino)methyl) phenol, was synthesized by treating the Schiff-base ligand with Mn(acac)3·4H2O and characterized by elemental analysis, IR spectra, thermogravimetric analyses and X-ray single-crystal diffraction. 1 has a similar new mixed-valence heptanuclear structure. The magnetic measurements indicate that 1 exhibits the antiferromagnetic interactions.
