臺灣位於板塊交界帶，聚合隱沒作用使地震頻繁且廣佈於不同深度範圍，地震資料豐富且完整，利於研究地震序列的特性。從地震目錄中可發現即使震源深度或地震規模相近的兩次地震，其餘震序列中的地震數量卻可相差達數倍之譜，故探尋餘震序列活動之特性為本研究首要之務。
本研究透過中央氣象局地震目錄中7.0≧M≧5.5之主震，對該主震之餘震序列進行臺灣各地區餘震產生率(K值)的分析研究與探討。K值可由Omori-Utsu Law：n(t) = K/(c+t)^p求得，將全台共119個7.0≧M≧5.5之餘震序列逐一計算出各序列K值後，即可分析比較K值與地震規模的關係、K值與震源深度的關係、地下熱流對K值的影響，並進行臺灣與美國加州地震序列特性之比較。研究最後發現K值並不會隨時間有明顯的變化，亦即每個地震序列皆可用單一個K值去描述餘震的產生率，且發現相同深度區間內之K值有隨地震規模增加而遞增之趨勢，而相同規模區間內之K值有隨地震深度增加而遞減之趨勢，且遞減率在10－20km之間有明顯轉折，此現象與地體構造之脆韌性分布有一致性。再考量地下熱流之影響，可見中央山脈與海岸山脈海拔較高處有較大的熱流值，使得此高熱流區之地溫梯度增加，地震數量因地層韌性增加而銳減，從研究中發現特定發生於高熱流區之餘震序列，其K值都有偏低之趨勢，此一趨勢與美國加州之餘震序列特性相似。

Taiwan is located at plate boundary where earthquakes are so frequently and widely distributed at different depth range. The frequent seismicity will help us to study the characteristics of the earthquake sequences. Note that even if two mainshocks are similar by earthquake magnitude or focal depth, the earthquake number of their aftershock sequences can vary up to several times. So, exploring the characteristics of the aftershock sequence activities is the top priority of this study. Our study used 7.0≧M≧5.5 earthquake sequences recorded by Central Weather Bureau (CWB) from 1991 to 2010; and analyzed the aftershock productivities (K value) of each aftershock sequence in Taiwan. K value of aftershock sequence are usually fitted by the Omori-Utsu law：n(t) = K/(c+t)p. After 119 7.0≧M≧5.5 aftershock sequence K value in Taiwan were calculated, we compared the relationship between K value and earthquake magnitude, focal depth, heat flow, and different tectonic blocks, respectively. We found that K value doesn’t change significantly with time; that is each aftershock sequence can be described as its aftershock productivities with a single K value. In addition, we found a trend that K value of the same depth level increases with increasing earthquake magnitude, while K value of the same magnitude decreases with increasing focal depth, and the decreasing rate turns noticeable at 10~20 km depth. This phenomenon can be explained by the brittle-ductile transition zone for a continental lithosphere. We also found that K value is low if the earthquake occurred in high heat flow area.

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