中国大陆及其周边板内地震活动的整体演化模式（一）
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摘要
以活断层网络为结构框架的中国大陆及其周边地区可视为一个“断层运动与蕴震”系统。用自耦合方法初步研究发现，该蕴震系统是一个时间结构有序的耗散系统。这种时间结构的有序是在远离平衡态的条件下，通过系统与环境物质、能量的交换而建立和维持的。它在演化过程中遵循着非平衡相变的若干特点，这就是临界慢化、分岔与减熵等。以能量积累的负反馈方式开始，以能量大释放的正反馈方式结束的螺旋式地震活动周期是中国大陆及其周边板内地震演化的基本方式。这也是地球螺旋运动的低层次之一。其地震活动的整体演化方程为研究还发现，该系统至少存在两种吸引子，即不动点和极限环。不管初始时刻系统处在何处，系统的最终行为完全由吸引子所制约。本世纪以来该系统已完整地经历了４个周期。以７０年代中期一系列大地震为标志的第四活动周期结束后，经过１０年（１９７９—１９８９年）规模不大的正反馈起伏振荡的亚高潮期，从１９９０年开始该系统进入了负反馈的能量再积累期。目前，负反馈的能量再积累已基本接近尾声，新的一轮正反馈系统演化将在今后几年内逐步展开。所以在今后若干年内该系统地震能量释放水平会有所增强，但不会快速增强。
With active fault network as the structural frame, China mainland and its circumferential area can be regarded as a fault movement and seismogenic system. The preliminary study with the self-coupling method shows that the seismogenic system is a time ordered dissipative one. The time order in the state of distance equilibrium is established and maintained through mass and energy exchanges between the system and surroundings. The seismogenic system evolution follows some properties of unbalanced phase change,namely, critical retard, bifurcation and entropy reduction, etc. The periodical seismicity beginning in the negative feedback form of energy acumulation and endding in the positive feedback form of large energy rapid release is the basic evolution pattern of seismicity in China mainland and its circumferential area.This is also one form of low-grade spiral motion of the earth. The globle evolution equation for the seismicity can be expressed as The study also shows that there exist at least two attractors-fixed point and limitcycle in the seismogenic system, no matter what state the system is at initial time, the final state of the system is completely controlled by the attractors.The seismogenic system mentioned above has experienced four complete periods since the beginning of this century. After the forth seismicity period symbolized by the series of large earthquakes in mid 1970,and after the ten-years (1979--1989 ) sub-climax phase with alternately positive and negative feedback in it,the system has entered another energy acumulation negative feedback stage, and the system is approaching the end of the negative feedback stage at present, and a new positive feedback phase will appear in a fewyears. So in some future years the earthquake energy release level in the system will rise but not rise rapidly.
With active fault network as the structural frame, China mainland and its circumferential area can be regarded as a fault movement and seismogenic system. The preliminary study with the self-coupling method shows that the seismogenic system is a time ordered dissipative one. The time order in the state of distance equilibrium is established and maintained through mass and energy exchanges between the system and surroundings. The seismogenic system evolution follows some properties of unbalanced phase change,namely, critical retard, bifurcation and entropy reduction, etc. The periodical seismicity beginning in the negative feedback form of energy acumulation and endding in the positive feedback form of large energy rapid release is the basic evolution pattern of seismicity in China mainland and its circumferential area.This is also one form of low-grade spiral motion of the earth. The globle evolution equation for the seismicity can be expressed as The study also shows that there exist at least two attractors-fixed point and limitcycle in the seismogenic system, no matter what state the system is at initial time, the final state of the system is completely controlled by the attractors.The seismogenic system mentioned above has experienced four complete periods since the beginning of this century. After the forth seismicity period symbolized by the series of large earthquakes in mid 1970,and after the ten-years (1979--1989 ) sub-climax phase with alternately positive and negative feedback in it,the system has entered another energy acumulation negative feedback stage, and the system is approaching the end of the negative feedback stage at present, and a new positive feedback phase will appear in a fewyears. So in some future years the earthquake energy release level in the system will rise but not rise rapidly.
引文
陈等，1989，分形与混沌在地球科学中的应用，学术期刊出版社，北京。金观涛，1987，整体哲学，四川人民出版社，成都。张之孟，1979，我国及邻区板内地震与板缘地震的关系，地震地质，Vol．1，No．3。
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