Supplement of Nat. Hazards Earth Syst. Sci., 20, 1533–1555, 2020 https://doi.org/10.5194/nhess-20-1533-2020-supplement © Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Supplement of Contrasting seismic risk for Santiago, Chile, from near-field and distant earthquake sources Ekbal Hussain et al. Correspondence to: Ekbal Hussain ([email protected]) The copyright of individual parts of the supplement might differ from the CC BY 4.0 License. 71.0°W 70.0°W 1. Santiago 2. 3. 4. Providencia 33.0°S 5. 6. 7. San Joaquin 8. 9. Pedro Aguirre Cerda 10. 11. Quinta Normal 32 31 12. 30 13 3 29 13. Conchali 12 2 14 11 4 14. Cerro Navia 15 28 10 1 5 15. 27 16 9 8 7 6 16. Cerrillos 17 18 22 26 21 17. Lo Espejo 33 19 18. 20 25 23 19. 24 20. La Pintana 21. San Ramon 22. La Granja 23. 24. Calera de Tango 25. 26. 27. Penalolen 28. 29. Las Condes 30. 31. Huechuraba 34.0°S 33.5°S 32. 33. 0 10 20 30 40 km 71.0°W 70.0°W Figure S1. Map showing the communes of the Santiago Metropolitan Region and the distribution of the residential building exposure model used in the risk calculations. The exposure model is downsampled to a 1×1 km grid from Santa-María et al. (2017). The red lines indicate the surface trace of the San Ramón fault used in the seismic risk scenario calculations, and the dashed cyan the buried fault splay. 2 Figure S2. A histogram of the number of buildings in the exposure model for Santiago against the number of storeys. The buildings are colour coded with the residential building class, where RC is reinforced concrete, MCF is confined masonry, MR is reinforced masonry, MUR is unreinforced masonry and W is wooden. The majority of residential buildings are 3 storeys or less, with mostly reinforced concrete structures comprising the 4+ storey buildings. 3 -70.55 -70.50 Mapped SRF Model SRF -33.40 -33.60 -33.50 0 1 2 3 4 km Figure S3. The mapped San Ramón Fault (SRF) shown in blue and the 4-segment model SRF used in the seismic risk calculations overlain on the Pleiades hillsided DEM. 4 Mw 7 Mw 7.5 Mw 6 Mw 6.5 PGA (fraction of g) PGA (fraction of g) 0.10 - 0.20 0.10 - 0.20 0.20 - 0.25 0.20 - 0.25 0.25 - 0.30 0.25 - 0.30 0.30 - 0.35 0.30 - 0.35 0.35 - 0.40 0.35 - 0.40 -33.4 -33.6 Intraslab Santiago Splay San Ramon Fault 0 5 10 15 20 km Mw 7 0 5 10 15 20 km Mw 7.5 Maule (USGS) Mw 8.8 Figure S4. The estimated median Peak Ground Acceleration (PGA) as a fraction of g. For the the San Ramón (red line) and Santiago splay fault (green line) cases, these represent estimates using the Akkar et al. (2014) ground motion prediction equation, while those for the intraslab fault are estimates from the Abrahamson et al. (2016) equation. Note that the scale is the same for the San Ramón and Santiago splay scenarios but different for the intraslab scenarios. The USGS peak ground accelerations for the Mw 8.8 Maule earthquake is shown at the bottom. 5 1 storey - Unreinforced masonry 1 storey - Light wood walls Villar-Vega [2017] Villar-Vega [2017] a b 2 storey - Reinforced masonry 9 storey - Concrete walls Villar-Vega [2017] Villar-Vega [2017] c d 2 storey - Unreinforced adobe 1 storey - Reinforced conrete Martins and Silva [2018] Martins and Silva [2018] e f Figure S5. A few examples of the range of fragility and vulnerability functions used within the scenario analysis. a-d are examples of building fragility functions from Villar-Vega et al. (2017a) with each colour coded line representing the probability of exceedance of a specific damage state for a given shaking intensity. The shaking intensity is represented by the Peak Ground Acceleration (PGA) in a, and by the spectral acceleration (Sa) in b-d at the elastic period (Telastic) indicated in the axis label. Figures e and f show two examples of replacement cost vulnerability curves showing the loss ratio (loss over exposed), for a given ground shaking intensity. The first, e is a continuous curve from Martins and Silva (2018) with the shaking intensity in spectral acceleration for a 2 storey unreinforced adobe building, while f shows a continuous vulnerability curve also from Martins and Silva (2018) against the PGA scale for a single storey reinforced concrete building. 6 -71.5 -71.0 -70.5 -70.0 -71.5 -71.0 -70.5 -70.0 Percentage collapse Percentage collapse -33.0 0 - 4 0 - 4 4 - 8 4 - 8 8 - 12 8 - 12 12 - 16 12 - 16 16 - 20 16 - 20 Vitacura 20 - 24 Las Condes 20 - 24 Santiago 24 - 28 24 - 28 Providencia La Reina Nunoa -33.5 Penalolen La Barnechea Macul La Florida Puento Alto Pirque San José de Maipo -34.0 San Ramon 0 10 20 30 40 km Mw 7 0 10 20 30 40 km Mw 7.5 Percentage collapse Percentage collapse -33.0 0 - 4 0 - 4 4 - 8 4 - 8 8 - 12 8 - 12 12 - 16 12 - 16 16 - 20 16 - 20 20 - 24 20 - 24 24 - 28 24 - 28 -33.5 San Joaquin San Miguel -34.0 Santiago splay 0 10 20 30 40 km Mw 6 0 10 20 30 40 km Mw 6.5 Percentage collapse Percentage collapse -33.0 0.0 - 1.5 0.0 - 1.5 1.5 - 3.0 1.5 - 3.0 3.0 - 4.5 3.0 - 4.5 4.5 - 6.0 4.5 - 6.0 6.0 - 7.5 6.0 - 7.5 7.5 - 9.0 7.5 - 9.0 Lo Prado Independencia Lo Espejo -33.5 San Joaquin Intra-slab -34.0 0 10 20 30 40 km Mw 7 0 10 20 30 40 km Mw 7.5 Figure S6. The distribution of collapsed building fraction in each comuna for the earthquakes considered in each scenario for the San Ramón Fault (green lines), the Santiago splay fault (dashed cyan line) and a deep intraslab fault. Note that the range of the colour scale changes between the upper four and lower pair of panels. 7 -71.5 -71.0 -70.5 -70.0 -71.5 -71.0 -70.5 -70.0 Fatality fraction Fatality fraction -33.0 (per thousand exposed) (per thousand exposed) 0 - 1 0 - 1 1 - 2 1 - 2 2 - 3 2 - 3 3 - 4 3 - 4 Santiago 4 - 5 Las Condes 4 - 5 Providencia La Reina La Cisterna Nunoa -33.5 Penalolen Macul La Florida Puento Alto San Miguel -34.0 San Ramon 0 10 20 30 40 km Mw 7 0 10 20 30 40 km Mw 7.5 Fatality fraction Fatality fraction -33.0 (per thousand exposed) (per thousand exposed) 0 - 1 0 - 1 1 - 2 1 - 2 2 - 3 2 - 3 3 - 4 3 - 4 4 - 5 4 - 5 Independencia Vitacura -33.5 -34.0 Santiago splay 0 10 20 30 40 km Mw 6 0 10 20 30 40 km Mw 6.5 Fatality fraction Fatality fraction -33.0 (per thousand exposed) (per thousand exposed) 0.0 - 0.2 0.0 - 0.2 0.2 - 0.4 0.2 - 0.4 0.4 - 0.6 0.4 - 0.6 0.6 - 0.8 0.6 - 0.8 0.8 - 1.0 0.8 - 1.0 Lo Espejo -33.5 San Joaquin Intra-slab -34.0 0 10 20 30 40 km Mw 7 0 10 20 30 40 km Mw 7.5 Figure S7. The fatality fraction, in fatalities per thousand exposed, in each comuna for the earthquakes considered in each scenario for the San Ramón Fault (green lines), the Santiago splay fault (dashed cyan line) and a deep intraslab fault. Note that the range of the colour scale changes between the upper four and lower pair of panels. 8 -71.5 -71.0 -70.5 -70.0 -71.5 -71.0 -70.5 -70.0 Replacement cost Replacement cost -33.0 USD (millions) USD (millions) 0 - 250 0 - 250 250 - 500 250 - 500 500 - 750 500 - 750 750 - 1000 Nunoa 750 - 1000 1000 - 1250 Las Condes 1000 - 1250 1250 - 1500 1250 - 1500 Santiago La Reina -33.5 Penalolen Macul La Florida Puento Alto -34.0 San Ramon 0 10 20 30 40 km Mw 7 0 10 20 30 40 km Mw 7.5 Replacement cost Replacement cost -33.0 USD (millions) USD (millions) 0 - 250 0 - 250 250 - 500 250 - 500 500 - 750 500 - 750 750 - 1000 750 - 1000 1000 - 1250 1000 - 1250 1250 - 1500 1250 - 1500 -33.5 -34.0 Santiago splay 0 10 20 30 40 km Mw 6 0 10 20 30 40 km Mw 6.5 Replacement cost Replacement cost -33.0 USD (millions) USD (millions) 0 - 50 0 - 50 50 - 100 50 - 100 100 - 150 100 - 150 150 - 200 150 - 200 200 - 250 200 - 250 250 - 300 250 - 300 300 - 350 300 - 350 Maipu 350 - 400 350 - 400 -33.5 Intra-slab -34.0 0 10 20 30 40 km Mw 7 0 10 20 30 40 km Mw 7.5 Figure S8. The residential building replacement cost, in USD millions, in each comuna for the earthquakes considered in each scenario for the San Ramón Fault (red lines), the Santiago splay fault (dashed blue line) and a deep intraslab fault.