The Organization of Convection in a Mei-Yu Frontal Rainband

鋒面雨帶之對流組織

周仲島(Ben Jong-Dao Jou) ； 鄧秀明(Shiung-Ming Deng)

《Terrestrial, Atmospheric and Oceanic Sciences》 9卷4期 (1998/12) Pp. 553-572

並列摘要

Twenty nine events recorded at three stations in the Chia-Nan area ofTaiwan showed split S waveforms with delay times ranging between 0.1and 0.2s.Aspect ratio method was applied to retrieve anisotropic propertiesof these phases.Data at station CHY were characterized by roughly EWfast direction that is parallel or sub-parallel to the compressional axis inthe region,as determined by other approaches.Stations ALS and SGSrecorded split waveforms that showed fast directions oblique with respectto the apparent regional compressional axis,but sub-parallel to that of theorientation of the secondary faults in the vicinity.To verify the anisotropicnature of splitting,6 events were selected to construct polarization patternsin which splitting was removed.The observed splitting-corrected polarizationsagreed with those given by reliably determined focal mechanisms ofthese events,therefore excluding extrinsic contributions from the sources.Analyses from ALS and SGS indicated that seismic anisotropy observed atlocal and regional scales may not be fully accounted for by the ExtensiveDilatancy Anisotropyc(EDA)theory but rather are controlled by conditionsin the local fault system.

並列關鍵字

Frontal Rainband ； Convection Organization ； Low-Level Jet ； Scale Interaction