Compared with first-order surface-related multiples from marine data,the onshore internal multiples are weaker and are always combined with a hazy and occasionally strong interference pattern.It is usually difficult t...Compared with first-order surface-related multiples from marine data,the onshore internal multiples are weaker and are always combined with a hazy and occasionally strong interference pattern.It is usually difficult to discriminate these events from complex targets and highly scattering overburdens,especially when the primary energy from deep layers is weaker than that from shallow layers.The internal multiple elimination is even more challenging due to the fact that the velocity and energy difference between primary reflections and internal multiples is tiny.In this study,we propose an improved method which formulates the elimination of the internal multiples as an optimization problem and develops a convolution factor T.The generated internal multiples at all interfaces are obtained using the convolution factor T through iterative inversion of the initial multiple model.The predicted internal multiples are removed from seismic data through subtraction.Finally,several synthetic experiments are conducted to validate the effectiveness of our approach.The results of our study indicate that compared with the traditional virtual events method,the improved method simplifies the multiple prediction process in which internal multiples generated from each interface are built through iterative inversion,thus reducing the calculation cost,improving the accuracy,and enhancing the adaptability of field data.展开更多
In practical seismic exploration, internal multiples generated when the wave impedance of medium is strong, and seismic records are recorded. The method of virtual event repress internal multiples is to move scattered...In practical seismic exploration, internal multiples generated when the wave impedance of medium is strong, and seismic records are recorded. The method of virtual event repress internal multiples is to move scattered points from underground to the surface, similar to the method of the surface-related multiple elimination (SRME). The method of SRME belongs to the prediction-subtraction approaches to eliminate internal multiples, prediction method is based on building a brand new way of seismic wave propagation (virtual reflection and virtual event), so that it has forward and backward wave propagation, and through convolution with significant wave to predict the internal multiples. Due to required data needing field information of full-wave, the authors use Seislet transform interpolating the missing data to ensure the premise of internal multiples prediction. The test data show that the above method has achieved good results.展开更多
March 2004 saw the beginning of the Beijing Capital International Airport expansion construction project. With a budget of 27 billion yuan($3.5 billion), the expanded construction project includes a third termi-nal an...March 2004 saw the beginning of the Beijing Capital International Airport expansion construction project. With a budget of 27 billion yuan($3.5 billion), the expanded construction project includes a third termi-nal and runways, a parking building, a traffic control center and relevant technologically advanced facilities. Will the new airport meet the requirements of the 2008 Olympic Games?In an interview with Beijing Review North American special correspondent Zong Xing, John Kasarda, Director of the Kenan Institute of Private Enterprise at the University of North Carolina at Chapel Hill and an expert on aviation infrastructure and logistics, shared his views on China's airport construction and airport economy.展开更多
基金the National Natural Science Foundation of China under Grant Nos.41974116 and 41930431Local Universities Reformation and Development Personnel Training Supporting Project from Central Authorities under Grant No.140119001 for supporting this work
文摘Compared with first-order surface-related multiples from marine data,the onshore internal multiples are weaker and are always combined with a hazy and occasionally strong interference pattern.It is usually difficult to discriminate these events from complex targets and highly scattering overburdens,especially when the primary energy from deep layers is weaker than that from shallow layers.The internal multiple elimination is even more challenging due to the fact that the velocity and energy difference between primary reflections and internal multiples is tiny.In this study,we propose an improved method which formulates the elimination of the internal multiples as an optimization problem and develops a convolution factor T.The generated internal multiples at all interfaces are obtained using the convolution factor T through iterative inversion of the initial multiple model.The predicted internal multiples are removed from seismic data through subtraction.Finally,several synthetic experiments are conducted to validate the effectiveness of our approach.The results of our study indicate that compared with the traditional virtual events method,the improved method simplifies the multiple prediction process in which internal multiples generated from each interface are built through iterative inversion,thus reducing the calculation cost,improving the accuracy,and enhancing the adaptability of field data.
基金Supported by the National Natural Science Foundation of China(40974054,41174080)the National Basic Research Program of China(973 Program)(2009CB219301)+1 种基金the National Innovation Research Project for Exploration and Development of Oil Shale(OSP-02,OSR-02)the National Public Benefit Scientific Research Foundation of China(201011078)
文摘In practical seismic exploration, internal multiples generated when the wave impedance of medium is strong, and seismic records are recorded. The method of virtual event repress internal multiples is to move scattered points from underground to the surface, similar to the method of the surface-related multiple elimination (SRME). The method of SRME belongs to the prediction-subtraction approaches to eliminate internal multiples, prediction method is based on building a brand new way of seismic wave propagation (virtual reflection and virtual event), so that it has forward and backward wave propagation, and through convolution with significant wave to predict the internal multiples. Due to required data needing field information of full-wave, the authors use Seislet transform interpolating the missing data to ensure the premise of internal multiples prediction. The test data show that the above method has achieved good results.
文摘March 2004 saw the beginning of the Beijing Capital International Airport expansion construction project. With a budget of 27 billion yuan($3.5 billion), the expanded construction project includes a third termi-nal and runways, a parking building, a traffic control center and relevant technologically advanced facilities. Will the new airport meet the requirements of the 2008 Olympic Games?In an interview with Beijing Review North American special correspondent Zong Xing, John Kasarda, Director of the Kenan Institute of Private Enterprise at the University of North Carolina at Chapel Hill and an expert on aviation infrastructure and logistics, shared his views on China's airport construction and airport economy.
