CAJ | 학술논문

本项成果包括:提出天然地震走时反演层析成像技术,采用下列方法使得处理结果得以改善:1)利用32个地震,404条射线的Pg,Sg,Pm,Sm,Pn,Sn等震相增加约束条件;2)用已有精度较高的人工地震测深结果作速度约束;3)用波形反演来修改模型,把波源,介质吸收,散射等物理特征集中反映在记录中,把诸多物理量开发出来互为约束,以修改后的模型再作反演,使解的稳定性大大提高;4)采用最优化过程,选择遗传算法,可以进行震源定位,走时反演,波形反演;5)得到任意深度的速度分布及从地表到Moho面的速度剖面.主要应用结果:对于朝鲜半岛南部,划分为5(沿纬度)*6(沿经度)*8(沿深度)块,对于中部分288块.得到从地表到Moho面的8个水平切面;中部地区沿纬度13个二维剖面及其Moho面深度分布.结果表明,这些剖面对认识大地构造、地质结构的稳定性,深部事件的性质是很有益的,对地球动力学研究也有重要意义.
본항성과포괄:제출천연지진주시반연층석성상기술,채용하렬방법사득처리결과득이개선:1)이용32개지진,404조사선적Pg,Sg,Pm,Sm,Pn,Sn등진상증가약속조건;2)용이유정도교고적인공지진측심결과작속도약속;3)용파형반연래수개모형,파파원,개질흡수,산사등물리특정집중반영재기록중,파제다물리량개발출래호위약속,이수개후적모형재작반연,사해적은정성대대제고;4)채용최우화과정,선택유전산법,가이진행진원정위,주시반연,파형반연;5)득도임의심도적속도분포급종지표도Moho면적속도부면.주요응용결과:대우조선반도남부,화분위5(연위도)*6(연경도)*8(연심도)괴,대우중부분288괴.득도종지표도Moho면적8개수평절면;중부지구연위도13개이유부면급기Moho면심도분포.결과표명,저사부면대인식대지구조、지질결구적은정성,심부사건적성질시흔유익적,대지구동역학연구야유중요의의.
A new technique of simultaneous inversion for 3-D seismic velocity structure using Pg, Sg, PmP, SmS, Pn and Sn arrival times of 32 events with 404 seismic rays are inverted for locations and crustal structure. These methods are applied to the Central and Southern parts of the Korean Peninsula. 3-D seismic velocity tomography including 8-sections from earth surface to the Moho, 13 profiles along latitude and longitude, and depth distribution was determined. The velocities fluctuate strongly in the upper crust. There are big an-isotrophy bodies near north of Seoul in the upper crust, implying that they may be related to the Chugaryong Rift Zone. They found that there were low velocity bodies beneath the Kyongju area at the depth 10- 15 km, the Youngwol area at the depth 10 kin, and the Hongsung area at the depth 5-10 km,indicating that they must be due to the earthquake sources of Kyongju (6/25/1997), Youngwol (12/13/1996), and Hongsung (10/07/1978), respectively. These results are also well consistent with Bouguer gravity anomalies showing very complex and Iow velocity bodies beneath the Chugarymng Rift Valley and/or deep fault systems and the earthquake hypocenters, respectively.