Introduction of New Seismic Ground Motion Parameter Zonation Map of China and Case Study Analysis in Lanzhou Region

Introduction of New Seismic Ground Motion Parameter Zonation Map of China and Case Study Analysis in Lanzhou Region Xiaojun LI Institute of Geophysics, China Earthquake Administration Korea 2012.10

Report Outline 1. Progress of China New Seismic Zonation Map 2. Case Study Analysis in Lanzhou Region 3. Some Ideas for Next Generation Seismic Zonation Map

The new seismic zonation map, called the fifth generation seismic map of China, or the second seismic ground motion parameter zonation map, is to accomplish the compiling work and will be issued in the end of this year (2012) The first seismic ground motion parameter zonation map was issued in 2001, which is the current map

The current (first) seismic ground motion parameter zonation map of China Consists of two maps and one table Two maps:peak ground acceleration map and spectral characteristic period map ¹þ û±õ ÎÚ ³Ä¾Æë ³ º ÉòÑô Òø ºôºÍ Æ Ø Ì«Ô Ê ±±¾ Ìì½ Ò Î Äþ À¼ÖÝ ¼ÃÄÏ Î ² Ö ÖÝ ÄÏ¾ ºÏ Ê ÉÏº À Èø É ¼ Îäºº º¼ÖÝ ÖØÇì ³ É³ ÄÏ²ý 反应谱特征周期 Tg, 秒 ¹óÑô ÖÝ 0 45 0 40 À Ã ÄÏÄþ ¹ãÖÝ Ì ±± 0 35 º Ú

S a / g The current (first) seismic ground motion parameter zonation map of China One table:for adjustment of spectral characteristic period Tg with site types a max m Characteristic period Tg(s) Tg Zone Site type I II III IV 1 zone 0.25 0.35 0.45 0.65 2 zone 0.30 0.40 0.55 0.75 3 zone 0.35 0.45 0.65 0.90 a max T a g max m ( ) 0 0.1 T g 6.0 T / s

New Seismic Ground Motion Parameter Zonation Map of China (2012) Consist of two maps and two tables Two maps:peak ground acceleration map and spectral characteristic period map

New Seismic Ground Motion Parameter Zonation Map of China (2012) Two tables:for adjustment of peak ground acceleration and spectral characteristic period Tg with site types Site type PGA(g) for site type II 0.05 0.10 0.15 0.20 0.30 0.40 I 0 0.72 0.74 0.75 0.76 0.85 0.90 I 1 0.80 0.82 0.83 0.85 0.95 1.00 II 1.00 1.00 1.00 1.00 1.00 1.00 III 1.30 1.25 1.15 1.00 1.00 1.00 IV 1.25 1.20 1.10 1.00 0.95 0.90 Tg(s) I 0 I 1 Site type II III IV 1 zone 0.20 0.25 0.35 0.45 0.65 2 zone 0.25 0.30 0.40 0.55 0.75 3 zone 0.30 0.35 0.45 0.65 0.90

New Seismic Ground Motion Parameter Zonation Map of China (2012) What is the difference for the new map? The main difference should be the table for adjustment of peak ground acceleration with change of site types In effect, it is to consider the influence of site condition on ground motion and also the nonlinear properties of site condition

The curves for adjustment of PGA with site types 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0.6 0.4 0.2 0.0 0.0 0.1 0.2 0.3 0.4 0.5 PGA Site PGA(g) for site type I type 0.05 0.10 0.15 0.20 0.30 0.40 I 0 0.90 0.90 0.90 0.90 0.90 0.90 I 1 1.00 1.00 1.00 1.00 1.00 1.00 II 1.25 1.22 1.20 1.18 1.05 1.00 III 1.63 1.53 1.38 1.18 1.05 1.00 IV 1.56 1.46 1.33 1.18 1.00 0.90

Sa (g) The curves for adjustment of Sa with site types 10 0.10g 1 0.1 0.01 0.01 0.1 1 10 T (s)

Sa (g) The curves for adjustment of Sa with site types 10 1 0.20g 0.1 0.01 0.01 0.1 1 10 T (s)

Report Outline 1. Progress of China New Seismic Zonation Map 2. Case Study Analysis in Lanzhou Region 3. Some Ideas for Next Generation Seismic Zonation Map

The map of potential seismic sources in China

The map of potential seismic sources in Lanzhou region

Potential seismic sources and active faults Source areas with high upper magnitude (such as 8.0, 8.5) Strong back ground source area (M7.5) in Lanzhou region

The map of PGA for return period of 1 in 475 years

Comparison of PGA distribution and potential sources

Report Outline 1. Progress of China New Seismic Zonation Map 2. Case Study Analysis in Lanzhou Region 3. Some Ideas for Next Generation Seismic Zonation Map

Some Ideas for Next Generation Seismic Zoning Map 1. Compile seismic zonation maps with different exceeding probabilities? Provide suitable design parameters of ground motion for different types of engineering structures The current and new seismic zontation map takes same PGA and Sa maps for different exceeding probabilities but adjusted values E.g.: K2:STE/ME(PGA) K3:SME/ME(PGA) 1.8~2.0 1/2.8~1/3.0 STE: strong earthquake, 2% probability of exceedance in 50 years ME: moderate earthquake, 10% probability of exceedance in 50 years SME: small earthquake, 63% probability of exceedance in 50 years

Some Ideas for Next Generation Seismic Zoning Map 2. Compiling seismic zonation maps with different ground motion parameters,such as peak ground acceleration, peak ground velocity and spectral accelerations? Provide suitable design parameters of ground motion for different types of engineering structures, such buildings, buried pipelines E.g., PGA and Sa are not suitable parameters but PGV

Some Ideas for Next Generation Seismic Zoning Map Why do we consider the deterministic method? For a active fault with stronger seismicity, such as recurrence period of less than several thousand years, it will very much underestimate the earthquake impact on the near field ground motion Because the potential source divided reduce the probability of earthquake ocuring

Some Ideas for Next Generation Seismic Zoning Map 3. Another issue discussed is how to considering the impact of the seismic potential source areas with high upper magnitude (such as 8.0, 8.5 and 9.0) on near-field ground motion in seismic zonation map compiling Comprehensive consideration of the probabilistic seismic hazard analysis method and deterministic seismic hazard analysis method was suggested to deal with the problem The near-field ground motion estimation method based on finite fault source should be adopted as the deterministic seismic hazard analysis method 34 43 34 41 34 39 34 37 34 35 34 33 34 31 34 29 34 27 34 25 34 23 34 21 34 19 34 17 34 15 34 13 34 11 108 8 108 84 108 88 108 92 108 96 109 109 04 109 08 109 12 109 16 109 2 PGA 34 43 34 41 34 39 34 37 34 35 34 33 34 31 34 29 34 27 34 25 34 23 34 21 34 19 34 17 34 15 34 13 34 11 390 375 360 345 330 315 300 285 270 255 240 225 210 195 180 165 150 135 120 105 90 75 60 45 30 15 0 34 09 34 09 34 07 108 8 108 85 108 9 108 95 109 109 05 109 1 109 15 109 2 34 07

Some Ideas for Next Generation Seismic Zoning Map Key point is how to determine the earthquake magnitudes and source models for different exceeding probabilities Study the relation of the calculating earthquake magnitude and the high upper magnitude of potential source Also study the relation of the calculating earthquake magnitude and the exceeding probability 震源模型滑动速率的时空变化图像

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