断块大地构造理论几乎涉及地震活动的各个方面:1)地震记录表明不但是强震,大多数6级以上地震也分布在构造块体边界上,构造块体控制了地震分布;2)地震活动规律体现在块体整体活动中。例如,鄂尔多斯地块周边单个断陷带的地震活跃期与平静期长短不一,无明显规律。但当把鄂尔多斯地块周边作为一个整体,其地震活动在时间上显示了准周期性;3)地块运动通过周边断层交替活动实现。从断层活动相互作用的时间间隔和错动形式出发可把它分为强震交替活动型(又可分长时间间隔和短时间间隔两类)和强震与弱震或断层蠕动交替活动型。强震交替活动型中时间间隔很短的双震活动较早被发现。强震交替活动型中时间间隔很长的类型虽然不易识别,但是依赖于中国历史地震目录,还是发现鄂尔多斯地块周边山西断陷带与渭河断陷带在历史上的3次交替活动等;强震与弱震或断层蠕动型的交替活动型很不容易被发现,仅在台网较密,观测条件较好的北京地区观测到。4)利用一些实验结果讨论了交替活动的规律。此外,结合断块大地构造理论对一些地震现象进行了讨论。
Fault-block tectonics concerns different aspects of earthquake activity as follows : 1 ) Most earthquakes with magnitudes over 6 occurr along the boundaries of different fault-blocks based on the catalogues of Chinese earthquakes. The fault-blocks control the distribution of earthquakes; 2)Characteristics of earthquakes is contained in the whole movement of blocks. For example,the active and quiescent periods of basin belts around the Ordos fault-block are different each other, and there was no obvious periodicity. However, if we regard the Ordos block as a whole,the seismicity around the Ordos block shows quasi-periodicity in some extent. 3) Block movement is accommodated by alternating slip of faults around the block. Based on the time interval and styles of unstable events occurred on the block boundary faults, their interaction may be divided into different types: alternating type of strong earthquakes and alternating type by a strong earthquake with weak earthquakes or aseismic slip. The former may be divided into long time interval and short time interval in addition. The alternating type of strong earthquakes with short time interval or type of double main shock has been taken noticed earlier. The alternating type of strong earthquakes with long time interval is not easy to recognize,fortunately, some examples are distinguished benefit from the Chinese earthquake record, for example, three alternating active periods of earthquakes on Shanxi and Weihe boundary faults of Ordos block. Alternating type by a strong earthquake with weak earthquakes or aseismic slip is difficult to identify, it can be observed only in the area with dense observational network and high resolution apparatus such as the Beijing area; 4)Characteristics of alternating slip of faults on the boundary of blocks is discussed based on the experimental results. Besides, some other earthquake phenomena are also discussed by fault-block tectonics.