| 摘要: | 台灣地區一直缺乏系統性地分析地震震源歷時、破裂速度、破裂長度及震源輻射能量與地震矩的 關係，而建立這些震源參數間的關係有助於了解台灣地震的孕震特徵。震源時間函數包含這些震源參 數的訊息，因此，藉由震源時間函數可以估算地震的震源歷時、破裂速度、破裂長度及震源輻射能量。 本計畫藉由非負解平滑化阻尼最小平方時間域解迴旋法決定台灣地區Mw 5.5 地震的震源時間函 數，首先，在震源處先產生一無震源歷時的合成遠場P 波，當成是經驗格林函數(EGF)；接著，再將 主震P 波訊號與EGF 進行時間域解迴旋以得到震源時間函數；最後，由震源時間函數推求各震源參 數，建立其與地震矩的關係。本研究被規劃為二年期計畫，在第一年計畫中，將利用震源時間函數推 估台灣地區地震的震源歷時、震源輻射能量與地震矩的關係；第二年則利用震源時間函數推估台灣地 區地震的破裂速度、破裂長度與地震矩的關係。
In Taiwan, it is lack to study systemically source duration, rupture velocity, rupture length and radiated seismic energy. To construct the relationships among source parameters is helpful to understand the seismogenic characteristics of earthquakes in the Taiwan region. A source time function includes information about these source parameters. Hence, from the derived source time function we can estimate the source duration, rupture velocity, rupture length and radiated energy. In this proposal, we use a damped least-squares time-domain deconvolution with smoothing and non-negative constraints to determine the source time functions for Mw5.5 earthquakes in Taiwan. To begin with, a synthetic far-field P-wave without source duration is created as the EGF at the position where the mainshock occurred; subsequently, the mainshock is deconvolved with the EGF to obtain the corresponding source time function; at last, the source parameters are estimated from the derived source time functions. The duration of this proposal is designed to be two years. In the first year, the target is to construct the relations among the source duration, radiated seismic energy, and seismic moment. In the secondary year, we attempt to examine the relations among the rupture velocity, rupture length, and seismic moment. |
