# Probabilistic Seismic Hazard Assessment for United Arab Emirates, Qatar and Bahrain
## 5 Selected Ground-Motion Attenuation Models
the Middle East, Europe, the Western United States and Japan), for the active shallow crustal regions. They considered attenuation models from five groups: (a) four models from the North Generation Attenuation-West2 (NGA-West2) Project [74; 75; 76; 77], (b) local attenuation models of Iran [78; 79; 80; 81; 82], (c) models from Turkey [83; 84], (d) two Japanese models [85; 32], and (e) models proposed for Europe and the Middle East [86; 87; 88]. They evaluated and compared the selected attenuation models against the local database in Iran (643 strong-motion records coming from 240 earthquakes within the magnitude range Mw 3.9 to 7.3, for Joyner-Boore distances up to 300 km). As a final conclusion for this study, the authors recommended the application of the region-specifically developed attenuation models by [PERSON] and [PERSON] [79], [PERSON] et al. [81], and [PERSON] et al. [82], as well as the regional attenuation models by [PERSON] et al. [32] and [PERSON] et al. [87], to assess the seismic hazard, considering the whole strong-motion database. In the current assessment, and taking into account the results from this recent published study, the most recent ground-motion attenuation models by [PERSON] et al. [81] and [PERSON] et al. [82], alongside the NGA-West2 model proposed by [PERSON] et al. [75], were considered within a logic-tree scheme (Figure 4). They were considered to characterize the attenuation characteristics for the active shallow crustal regions for the considered seismic source models. Additionally, the ground-motion model developed by [PERSON] et al. [32] was considered for the defined intermediate-depth seismic sources (IN-01 and IN-02, see Figure 2b) proposed in the source model by [PERSON] et al. [2]. Those selected model [81; 82; 75; 81] were found to be the best compatible ground-motion attenuation models in terms of their magnitude, distance, and period range definitions. The first selected attenuation model by [PERSON] et al. [81] was considered for the active shallow crustal seismic sources (Figure 4). This attenuation model was developed using the Iranian strong-motion database. It was developed to predict the PGA and the pseudospectral accelerations (for 5% damping ratio) for oscillation periods up to 4.0 s. This ground-motion prediction model is accounting the style of faulting and the site conditions according to the European Committee for Standardization EC-8 [89]. The distance measure in this model is the horizontal distance to the surface projection of the rupture plane (the Joyner-Boore distance \(\mathrm{R_{JB}}\)). It is valid for a moment magnitude range of \(4.0\leq\mathrm{Mw}\leq 7.3\), and for distances up to 200 km. The second considered attenuation model is that developed by [PERSON] et al. [82] (Figure 4). It was also developed specifically for Iran. This attenuation model includes PGA and pseudospectral acceleration ordinates (5% damping ratio) for oscillation periods ranging from 0.01 s to 4.0 s. It is valid within a moment magnitude range of \(4.8\leq\mathrm{Mw}\leq 7.5\), and for rupture distances (\(\mathrm{R_{rup}}\)) up to 400 km, taking into consideration the faulting mechanisms. In addition, it includes a definition for the soil conditions based on the value of the average shear-wave velocity for the upper 30 m of soil (\(\mathrm{V_{S,30}}\)). In the current study, a value of 760 m/s for this parameter has been considered, reflecting the B/C NEHRP boundary site class  
Figure 4: Ground-motion attenuation models considered in the current assessment (for magnitudes Mw 5.0 and 7.0), for the B/C NEHRP boundary site class. boundary, i.e., the transition between very dense soil and soft rock conditions. The third selected attenuation model is that developed for shallow crustal regions by [PERSON] et al. [75] which considered as one from the NGA-West2 models (Figure 4).