# Seismic Risk in Alborz: Insights from Geological Moment Rate Estimation and Fault Activity Analysis
## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Fault Name** & **Ms (Av)** & **SRL lr** & **WR** & **AR** & **Fault Name** & **Ms (Av)** & **SRL lr** & **WR** & **AR** \\ \hline Sangavar & 7.24 & 0.204 & 0.564 & 0.267 & Jagatai & 7.02 & 0.194 & 0.554 & 0.257 \\ Masuleh & 7.33 & 0.208 & 0.568 & 0.272 & F2 & 7.56 & 0.218 & 0.578 & 0.282 \\ F33 & 5.91 & 0.143 & 0.496 & 0.199 & Jajarm & 7.14 & 0.2 & 0.56 & 0.262 \\ Talesh & 7.86 & 0.231 & 0.59 & 0.296 & F36 & 7.31 & 0.207 & 0.567 & 0.27 \\ F33 & 6.58 & 0.174 & 0.533 & 0.234 & Rabat Garbil & 7.41 & 0.212 & 0.572 & 0.276 \\ Rudbar & 6.7 & 0.179 & 0.538 & 0.24 & Sfarayen & 6.75 & 0.182 & 0.541 & 0.243 \\ F32 & 6.77 & 0.183 & 0.542 & 0.244 & Sabzevar & 5.69 & 0.132 & 0.482 & 0.186 \\ Lahijan & 6.77 & 0.182 & 0.542 & 0.244 & Doruneh1 & 6.6 & 0.175 & 0.534 & 0.235 \\ F31 & 6.86 & 0.187 & 0.546 & 0.248 & Doruneh2 & 6.74 & 0.181 & 0.541 & 0.242 \\ North Rudbar & 7.36 & 0.209 & 0.57 & 0.273 & Torud & 7.23 & 0.203 & 0.564 & 0.267 \\ Bonan & 7.2 & 0.202 & 0.562 & 0.265 & F8 & 6.5 & 0.17 & 0.529 & 0.23 \\ Alamturd & 7.47 & 0.214 & 0.574 & 0.278 & F9 & 7.02 & 0.194 & 0.554 & 0.257 \\ F21 & 6.34 & 0.163 & 0.52 & 0.222 & F10 & 6.7 & 0.179 & 0.539 & 0.24 \\ F22 & 6.78 & 0.183 & 0.543 & 0.244 & F11 & 7.14 & 0.199 & 0.56 & 0.262 \\ F23 & 5.95 & 0.144 & 0.498 & 0.201 & Ghachab & 6.75 & 0.182 & 0.541 & 0.243 \\ F24 & 6.36 & 0.163 & 0.521 & 0.222 & Pishva & 6.74 & 0.181 & 0.541 & 0.242 \\ North Ghazvin & 7.03 & 0.194 & 0.554 & 0.257 & Garmsar & 7.14 & 0.2 & 0.56 & 0.262 \\ Zanjan & 7.32 & 0.208 & 0.568 & 0.271 & Eyvanaki & 7.32 & 0.208 & 0.568 & 0.271 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Surface rupture length (SRL) in meters, rupture width (WR) in meters, and rupture area (AR) in square meters of each earthquake by the fault activities. Ms (Av) is the mean magnitude. [PERSON] [34] studied 670 acceleration maps from various countries, including 100 from Japanese earthquakes and 210 from California. From this analysis, he proposed Equation (7) to calculate the maximum acceleration of gravity:  
\[\text{Y}=1.320\text{ exp}(0.58\text{ Mb})/(\text{R}+25)\dot{1}.52 \tag{7}\]  
Additionally, [PERSON] [35] provided Equation (8) for shallow earthquakes with magnitudes ranging from 5 to 7.7 and distances of less than 50 km between the earthquake source and the site, considering solid rock or alluvial sediments:  
\[\text{Y}=0.0159\text{ exp}(0.868\text{ M})\text{ [R}+0.0606\text{ exp}(0.7\text{ M})]\dot{1}-1.09 \tag{8}\]  
Equations (7) and (8) were used to calculate the maximum horizontal ground acceleration due to gravity in the study area, and the results are presented in Table 6. A network of 1565 points in the study area was analyzed to generate the seismic hazard map. Fault lengths were calculated using the X-Tools lateral extension in the ArcGIS software 10.6, and the distances between each fault and the center of each point were determined using the ArcView software. The PGA values were then interpolated and mapped to the PGA points, as shown in Figure 5. The Qasr-e Firuzeh and Sornk-e Hear fault systems (F14), located approximately 7.5 km southeast of Tehran, were found to have a seismic magnitude of 6.3 Richter and a gravity acceleration of 0.55723 g.