Presently the research based on the accurate seismic imaging methods for surface relief, complex structure, and complicated velocity distributions is of great significance. Reverse-time migration is considered to be o...Presently the research based on the accurate seismic imaging methods for surface relief, complex structure, and complicated velocity distributions is of great significance. Reverse-time migration is considered to be one of highly accurate methods. In this paper, we propose a new non-reflecting recursive algorithm for reverse-time migration by introducing the wave impedance function into the acoustic wave equation and the algorithm for the surface relief case is derived from the coordinate transformation principle. Using the exploding reflector principle and the zero-time imaging condition of poststack reverse- time migration, poststack numerical simulation and reverse-time migration with complex conditions can be realized. The results of synthetic and real data calculations show that the method effectively suppresses unwanted internal reflections and also deals with the seismic imaging problems resulting from surface relief. So, we prove that this method has strong adaptability and practicality.展开更多
The year of 2000 is at the turn of the century as well as of the millennium. Themankind waves farewell to the 20th century as well as the second millenniumand welcomes the 21st century and the third millennium. At thi...The year of 2000 is at the turn of the century as well as of the millennium. Themankind waves farewell to the 20th century as well as the second millenniumand welcomes the 21st century and the third millennium. At this special juncture,looking closely at the future based on understanding which was obtained from re-viewing and summarizing the past and present world politics from historical andphilosophical standpoints, we can find that it has become an unavoidable subject onhow to regard the trend of the world pattern toward multi-polarization and respon-sibility adjustment arising from it.展开更多
The difference between human and animals is that human not only obey the rules of nature and history but also possess subjective attitude and spirit of life, which are presented as life values by reflecting directly o...The difference between human and animals is that human not only obey the rules of nature and history but also possess subjective attitude and spirit of life, which are presented as life values by reflecting directly on ideology. According to it,Greek mythology pours out its life values based on its subjective attitude and spirit of life.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 40974073)the National 863 Program (Grant No.2007AA060504)the National 973 Program (Grant No. 2007CB209605) and CNPC Geophysical Laboratories
文摘Presently the research based on the accurate seismic imaging methods for surface relief, complex structure, and complicated velocity distributions is of great significance. Reverse-time migration is considered to be one of highly accurate methods. In this paper, we propose a new non-reflecting recursive algorithm for reverse-time migration by introducing the wave impedance function into the acoustic wave equation and the algorithm for the surface relief case is derived from the coordinate transformation principle. Using the exploding reflector principle and the zero-time imaging condition of poststack reverse- time migration, poststack numerical simulation and reverse-time migration with complex conditions can be realized. The results of synthetic and real data calculations show that the method effectively suppresses unwanted internal reflections and also deals with the seismic imaging problems resulting from surface relief. So, we prove that this method has strong adaptability and practicality.
文摘The year of 2000 is at the turn of the century as well as of the millennium. Themankind waves farewell to the 20th century as well as the second millenniumand welcomes the 21st century and the third millennium. At this special juncture,looking closely at the future based on understanding which was obtained from re-viewing and summarizing the past and present world politics from historical andphilosophical standpoints, we can find that it has become an unavoidable subject onhow to regard the trend of the world pattern toward multi-polarization and respon-sibility adjustment arising from it.
文摘The difference between human and animals is that human not only obey the rules of nature and history but also possess subjective attitude and spirit of life, which are presented as life values by reflecting directly on ideology. According to it,Greek mythology pours out its life values based on its subjective attitude and spirit of life.
