Spatial distribution of bedrock level peak ground acceleration in the National Capital Region of India using geographic information system

Figures & data

Figure 1. Study area, the NCR of India. Source: Author.

Figure 2. Seismotectonic map of the study area. Source: Author.

Figure 3. Study area showing (a) the faults, and (b) earthquake events from 1802 to 2020.

Source: Author.

Figure 4. Linear regression relation (a) between M_L and M_S, and (b) between M_W and M_L. Source: Author.

Figure 5. A map of the control region showing 1944 mutually exclusive seismic events.Source: Author.

Figure 6. Check for the completeness of seismic data for (a) Region I, and (b) Region II. Source: Author.

Table 1. Completeness of homogeneous earthquake catalogue with respect to time.

	Approximate years of completeness
Magnitude (Mw)	Region I	Region II
3.0 ≤ Mw < 4.0	20	20
4.0 ≤ Mw < 5.0	40	60
5.0 ≤ Mw < 6.0	50	90
Mw ≥ 6.0	80	100

Table 2. List of calculated seismic parameters and its comparison with reported values for the region.

Parameter		NCS-MoES (2016)	NDMA (2010)	Iyengar and Ghosh (2004)	Present study
Region I	a	2.64 ± 0.16	Not reported	Not reported	2.47 ± 0.21
	b	0.59 ± 0.03	Zone 2: .73 ± 0.04 Zone 3: .78 ± 0.04	0.78	0.67 ± 0.04
	Mc	4.0	Not reported	Not reported	3.00
Region II	a	0.62 ± 0.08	Not reported	Not reported	1.48 ± 0.20
	b	0.42 ± 0.12	Zone 28: .81±.06	0.87	0.58 ± 0.04
	Mc	3.0	Not reported	Not reported	2.10

Figure 7. Estimation of Mc, a, and b parameters for (a) Region I, and (b) Region II. Source: Author.

Figure 8. Gutenberg - Richter relation for the Region I and II. Source: Author.

Figure 9. Earthquakes associated with each fault. Source: Author.

Table 3. Deaggregation of faults.

Fault ID	Fault name	Length of fault (Km)	Mmax	Shortest hypocentral distance (Km)	No. of earthquake associated	αi	χi	Average of αi and χi
1	Great Boundary Fault (GBF)	320	7.3	114	6	0.17	0.07	0.12
2	Mahendraghar-Dehradun fault (MD)	295	5.7	82	27	0.15	0.30	0.23
3	Moradabad	170	6.1	59	5	0.08	0.05	0.07
4	Chahapoli	215	5.7	137	6	0.11	0.07	0.09
5	Sabi Fracture	200	4.9	74	8	0.10	0.09	0.09
6	Near Mathura	92	4.8	92	3	0.05	0.03	0.04
7	Fault Parallel to no. 6	115	4.8	66	3	0.06	0.03	0.04
8	Fault left of Alwar	126	4.9	127	6	0.07	0.07	0.07
9	Fault near Alwar	53	4.9	84	6	0.03	0.07	0.05
10	Fault near Jaipur	117	5.1	205	5	0.06	0.05	0.05
11	Mathura	101	7.3	63	4	0.05	0.04	0.04
12	Main Central Thrust (MCT)	355	7.3	223	174	0.34	0.54	0.44
13	North Almora Thrust (NAT)	279	7.1	210	49	0.16	0.15	0.15
14	Main Boundary Thrust (MBT)	464	6.5	157	21	0.32	0.06	0.19
15	Alakananda	50	7.3	219	51	0.03	0.16	0.09
16	Ropar	37	5.5	260	3	0.02	0.01	0.01
17	Near Ramgarh	38	6.5	230	5	0.02	0.02	0.02
18	South Almora Thrust (SAT)	193	6.5	211	15	0.11	0.05	0.08
19	Sohna Fault	107	5.4	75	18	0.06	0.20	0.13

Figure 10. Fault level recurrence relation for (a) Region I, and (b) Region II. Source: Author.

Figure 11. Grids used for PSHA in the NCR of India. Source: Author.

Figure 12. PGA vs. Hypocentral distance for M_w 7.0. Source: Author.

Figure 14. PGA at rock level for (a) 2% probability of exceedance in 50 years, (b) 2% probability of exceedance in 100 years, (c) 10% probability of exceedance in 50 years, and (d) 10% probability of exceedance in 100 years. Source: Author.

Table 4. Comparison of PGA values estimated in the present study with past results.

	PGA (g) value
	2% probability of exceedance in		10% probability of exceedance in
	50 years	100 years	50 years	100 years
Present Study	0.12 − 0.37	0.15 − 0.40	0.07 − 0.33	0.08 − 0.35
Sarkar and Shankar (2017)	0.00 − 0.64	Not Reported	0.00- 0.37	Not Reported
NCS-MoES (2016)	0.08 − 0.16	Not Reported	0.04 − 0.08	Not Reported
Rao and Rathod (2014)	0.14 − 0.23	Not Reported	Not Reported	Not Reported
Iyengar and Ghosh (2004)	0.19 − 0.24	Not Reported	Not Reported	Not Reported

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Data availability statement

The authors confirm that some portion of the data supporting the findings of this study is available within the article. Some of the raw data were generated at our laboratory and derived data supporting the findings of this study are available from the corresponding author [J.D.], upon reasonable request.