표제지
제출문
보고서 요약서
요약문
SUMMARY
목차
제1장 연구개발과제의 개요 17
제1절 연구개발 목적 및 필요성 17
제2절 연구개발 내용 및 범위 18
제2장 국내외 기술개발 현황 19
제3장 연구개발수행 내용 및 결과 21
제1절 개요 21
제2절 강지진동 추정을 위한 접근 방법 24
1. 서론 24
2. 방법론 25
3. 수치모의 예 28
4. 토의 및 결론 35
제3절 수치모의 기반 구축을 위한 속도구조 모델 37
1. 서론 37
2. 자료 처리 38
3. 레일리파 토모그래피 43
4. 결론 46
제4절 지진원 요소 분석: 2006년 4월 울집앞바다 연쇄지진과 울릉분지 서측 경계부에서의 지진활동 기원 48
1. 서론 48
2. 지진자료 50
3. 단층면 해 52
4. 진원 재결정 55
5. 토의 및 결론 59
제5절 한반도 주변지역 지진 모서리주파수의 거리 종속성 61
1. 서론 61
2. 자료와 방법 62
3. 결과 및 토의 65
4. 결론 및 제언 72
제6절 한반도 장주기 지반운동과 지진재해 잠재성 74
1. 서론 74
2. 속도구조 모델 76
3. 지진파 전파 모델링 82
4. 지진원 파라미터 110
5. 장주기 지진 지반운동 수치모의 115
제4장 목표달성도 및 관련분야에의 기여도 126
제5장 연구개발 결과의 활용계획 129
제6장 연구개발과정에서 수집한 해외과학기술정보 130
제7장 참고문헌 131
표 2-1. Comparison of numerical modeling parameters for the circular Rupture simulation. 32
표 4-1. List of events in the Aprill 2006 earthquake sequence, offshore Uljin, Korea. These are compiled from catalog of the Korea Institute of Geoscience and Mineral Resources (KIGAM, http://quake.kigam.re.kr). 50
표 4-2. Input data used in focal mechanism analysis for the event 2006/04/29 with origin time 11:01:13.05. 53
표 4-3. Velocity model (Chang and Baag, 2006) used for relocation of events in this study. 56
표 4-4. Relocated hypocenters in comparison with hypocenters from the KIGAM catalog. 56
표 5-1. Earthquake data set 67
그림 2-1. Schematic representation of a three-dimensional grid layout with localized discontinuous grids (Kang and Baag, 2004b). The model consists of two regions with different grid spacing that satisfy the local stability conditions based on minimum velocity in a specific region. Discontinuous... 26
그림 2-2. Model for simulating strong ground motion by dynamic rupture. Grids and time steps near the fault region are gradually refined in the same way as in the localized sedimentary basins. 27
그림 2-3. Displacement distributions over a fault plane during rupture propagation 28
그림 2-4. Displacements at several point on the fault plane depicted in Fig. 3. The numerical solution (blue line) is compared with the analytical solution (red line). The analytical solution is based on Kostrov(1964). 29
그림 2-5. Gradually refined model of the fault zone. The prescribed fault boundary in indicated by a yellow line. Twelve observation points are located at the free surface to compare the results of the LVTS scheme with those of the CGTS scheme. Ruputre initiates at the left end of the fault boundary, and the... 30
그림 2-6. Ground velocities at the free surface for the gradually refined fault zone model. Observations locations are indicated in Fig. 2-5. Numerical results calculated using the LVTS scheme (blue line) are compared with those obtained using the CGTS scheme (red line). 31
그림 2-7. Basin bottom topography in the Hongseong area, Korea(Kang and Bagg, 2004b). Contours show the distribution of depth to bedrock in a small-scale basin woth depth interval of 5 meters. The thick line with a star indicates surface profection of the hypothetical fault plane of the 1978... 33
그림 2-8. Snapshots of ground velocities radiated by dynamic rupture on the fault in the region with three-times finer sampling parameters (green rectangle in Fig. 2-7) 34
그림 3-1. Map showing locations of the 91 accelerograph stations of the selsmic networks in the southern Korea. The networks are operated by Korea Meteorological Administraction (KMA), Korea Institute of Geoscience and Mineral Resources (KIGAM), and Universites. The curved line connecting the Yellow Sea and the East Sea in the northern area indicates Demilitarized zone between North Korea and South Korea. 39
그림 3-2. Continuous noise records at stations GKP1 and BRD in one day long 40
그림 3-3. Rayleigh wave green's functions between accelerograph stations in pairs, (A) Ray paths where Rayleigh wave group velocities are measured by cross-correlating ambient seismic noise (straight lines). The paths are constructed from the 1843 station pairs having correlated sesmograms with a... 41
그림 3-4. Cross-correlation functions for all component pairs computed from the rotated three component records at stations CHJ and ULS with the inter-station distance of 190 km. The inter-station great circle path in the radial direction. Labels on ezch trace indicate verical (Z), redial (R), and... 42
그림 3-5. Result of checkerboard test with cell hit count. (A) Map showing the number of rays passing through each cell designed for invercion. A square cell has a size of 12 km in length. The hit count in each cell in indicated by the color of the circle. (B) Result of checkerboard test using a square inversion cell... 44
그림 3-6. Group velocity distribution in comparison with geological features in the southern Korean Peninsula. (A) Map showing geology and tectonic provinces of the study area, which is modified from the geolgical and tectnic maps of Korea in a scale of 1:1,000,000. The geology isn classfied to three types and each... 45
그림 4-1. Epicentral locations (open circles) of the Aprill 2006 earthquake sequence on a topographic relief map of the East Sea. Beachball shows the epicenter and lower hemisphere focal mechanism of the 29 May 2004, Mw 5.1, earthquake. Solid triangles indicate the closest three stations to...(이미지참조) 49
그림 4-2. Doublet observed on seismograms at station UCN for the event 09:49:34 on 19 Aprill 2006. Arrivals of P and S waves for the preceding event (09:49:25) are indicated by P1 and S1, respectively, while P2 and S2 correspond to the following event (09:49:34). The marks U, E, and N denote the vertical,... 51
그림 4-3. Vertical component seismograms recorded at the station UCN for all the events of the Aprill 2006 sequence listed in Table 1. The seismograms are aligned on the direct P arrivals and bandpass filtered between 0.1 and 10 Hz. The numbers on the left side denote the event number assigned in Table 1. All the traces are normalized to the same scale. 52
그림 4-4. Focal mechnism (lower hemisphere projection) obtained by inversion of P and SH polaities and SH/P amplitude raions for the event 11:01:13on 29 Aprill 2006 (M₁3.2). 54
그림 4-5. Relocated gypocenters for the nine events of the Aprill 2006 sequence. (A) epicenter map, (B) vertical cross-section alon the east-west direction, and (C) vertical cross-section along the north-south direction. In (A), the... 58
그림 5-1. Epicenter location (circles) and broadband seismograph stations (triangle) 63
그림 5-2. Three-component seismograms and corresponding displacement amplitude spectra. (a) 20 January 2007, M₁= 4.9, recorded at Napori(NPR) at a distance of 239 km. (b) 4 October 2007, M₁= 3.0, recorded at Hongseong (HSB) at a distance of 266 km. Amplitudes are normalized to the maximum of each station. 64
그림 5-3. Observed comer frequency versus hypocentral distance. 70
그림 5-4. Observed corner frequency versys hypocentral distance for 3 groups of events along moment magnitude listed in Table 1. (a) Mw < 3.0 (b) 3.0 ≤ Mw < 4.0 (c) Mw ≥ 4.0.(이미지참조) 71
그림 5-5. Low-frequency spectral level versus gypocentral distance. 72
그림 6-1. Locations of the 91 accelerograph stations and total 4095(=91x90/2) ray paths 77
그림 6-2. Example of data processing (a) Raw seismogram of August 15, 2008 with 1 samples per second in one day length for AND station. (b) The seismogram after removing mean value and linear trend (b) and (c) redult of high-pass... 78
그림 6-3. Travel time - distance plot of selected cross-correlation seismograms in 0.4Hz center frequency. 79
그림 6-4. Synthetic checker board test result for damping value. 80
그림 6-5. Number of Cell hit 81
그림 6-6. Variation of average Rayleigh-wave group-velocity with frequency 82
그림 6-7. Rayleigh-wave group-velocity tomographic map for a frequency band with the central frequency of 0.15 Hz 83
그림 6-8. Rayleigh-wave group-velocity tompgraphic map for a frequency band with the central frequency of 0.2 Hz. 84
그림 6-9. Rayleigh-wave group-velocity tompgraphic map for a frequency band with the central frequency of 0.25 Hz. 85
그림 6-10. Rayleigh-wave group-velocity tompgraphic map for a frequency band with the central frequency of 0.3 Hz. 86
그림 6-11. Rayleigh-wave group-velocity tompgraphic map for a frequency band with the central frequency of 0.35 Hz. 87
그림 6-12. Rayleigh-wave group-velocity tompgraphic map for a frequency band with the central frequency of 0.4 Hz. 88
그림 6-13. Rayleigh-wave group-velocity tompgraphic map for a frequency band with the central frequency of 0.45 Hz. 89
그림 6-14. Typical examples of dispersion curve and depth inversion 90
그림 6-15. S-wave velocity distribution maps at depth of 0.25 km 91
그림 6-16. S-wave velocity distribution maps at depth of 0.75 km 92
그림 6-17. S-wave velocity distribution maps at depth of 1.25 km 93
그림 6-18. S-wave velocity distribution maps at depth of 1.75 km 94
그림 6-19. S-wave velocity distribution maps at depth of 2.25 km 95
그림 6-20. S-wave velocity distribution maps at depth of 2.75 km 96
그림 6-21. S-wave velocity distribution maps at depth of 3.25 km 97
그림 6-22. S-wave velocity distribution maps at depth of 3.75 km 98
그림 6-23. S-wave velocity distribution maps at depth of 4.25 km 99
그림 6-24. S-wave velocity distribution maps at depth of 4.75 km 100
그림 6-25. S-wave velocity distribution maps at depth of 5.25 km 101
그림 6-26. S-wave velocity distribution maps at depth of 5.75 km 102
그림 6-27. S-wave velocity distribution maps at depth of 6.25 km 103
그림 6-28. S-wave velocity distribution maps at depth of 6.75 km 104
그림 6-29. S-wave velocity distribution maps at depth of 7.25 km 105
그림 6-30. S-wave velocity distribution maps at depth of 7.25 km 106
그림 6-31. S-wave velocity distribution maps at depth of 8.25 km 107
그림 6-32. The background 3-D velocity model is constructed through a 3-D spatial interpolation of velocity profiles from the receiver funtion study at the broadband stations in southern Korea (Chang and Baag, 2004, 2005). 108
그림 6-33. Final 3-D shear-wave velocity model of the southern Korean Peninsula combiring the short-period information inverted from dispersion curves of Rayleigh-wave group velocities and the broadband information through interpolation of velocity profiles obtained from the receiver-funtion studies. 109
그림 6-34. Source information of the March 20th, 2005, Mw 6.7 Fukuoka, Japan, earthquake and the January 20, 2007, Odaesan, Korea, earthquake. 111
그림 6-35. distribution of the maminshock and aftershocks of the March 20, 2005 Fukuoka earthquake. Inlet indicates the focal mechanism solutions of the mainshock using the Hi-net and F-net seismograms(http://www.k-net.bosai.go.jp/k-net/topics/fukuoka050320). 113
그림 6-36. Slip distribution (top) and moment rate functions on the falult rupture plane of the Fukuoka earthquake (http://www.k-net.bosai.go.jp/k-net/topic/fukuoka050320). 114
그림 6-37. Snapshots of the rupture propagation (http://www.k-net.bosai.go.jp/k-net/topic/fukuoka050320). 115
그림 6-38. Snapshots of map view of the wavefields for 3-D velocity structure model simulated using finite-difference method 117
그림 6.39. Map of observed peak ground acceleration in a frequency band of 0.1~0.5 Hz 118
그림 6.40. Map of simmulated peak ground acceleration in a frequency band of 0.1~0.5 Hz 119
그림 6.41. Map of simmulated peak ground velocity in a frequency band of 0.1~0.5 Hz 120
그림 6-42. Location of broadband stations where the observed ground motions of the Odaesan earthquake are compared with the calculated ground motions. 121
그림 6-43. Results of a 3-D finite-difference simulation. The figure compares calculated (top) velocity waveforms with observed velocity waveforms at some broadband stations in the southern Korean Peninsula. 122
그림 6-44. Results of a 3-D finite-difference simulation of the 20 March 2005, Mw 6.7, fukuoka, Japan, earthquake. Snapshots are for vertical cross section across the east-west direction in latitude 36˚N. Vertical depth is wxaggerated 3 times than horizontal length scale. 124