Supplementary Tables

Table S1 Focal mechanism of the aftershocks

No Date Time Lat °N Lon °E

Depth

(km) Mw

Strike

(°)

Dip

(°)

Rake

(°)

No of

stations

VR

(%)

DC

(%)

1. 20140126 14:59 38.3099 20.4254 10 4.2 210 75 178 7 23 90

2. 20140126 18:45 38.2323 20.3790 7 5.2 148 65 57 6 35 87

3. 20140126 19:03 38.1962 20.4075 14 4.3 10 76 174 6 57 99

4. 20140126 19:12 38.2502 20.4128 14 4.3 18 87 177 6 44 55

5. 20140126 21:15 38.1570 20.3337 8 4.5 29 79 -177 6 55 93

6. 20140126 21:42 38.1928 20.4990 9 3.8 254 63 -7 6 36 92

7. 20140126 23:06 38.236 20.4077 6 4.2 165 65 71 7 71 70

8. 20140127 09:47 38.1510 20.4192 4 4.1 139 61 55 6 39 94

9. 20140127 13:05 38.2355 20.4127 3 4.4 206 88 -161 7 61 82

10. 20140127 15:39 38.3845 20.4432 5 4.2 196 75 -157 7 76 70

11. 20140128 01:05 38.2608 20.3997 3 3.9 293 53 5 7 83 98

12. 20140128 08:07 38.2168 20.4877 19 4.0 101 43 6 6 37 38

13. 20140128 14:49 38.2397 20.4877 13 3.9 48 89 -173 6 59 89

14. 20140128 19:12 38.4068 20.5005 2 4.4 194 89 -117 7 78 77

15. 20140128 22:22 38.4145 20.4965 2 4.2 103 62 -1 8 52 90

16. 20140128 22:23 38.4083 20.4557 3 4.1 112 49 22 6 63 95

17. 20140130 11:06 38.4143 20.4957 3 4.5 9 70 148 8 74 73

18. 20140131 06:52 38.4173 20.4875 5 4.3 13 79 173 7 65 93

19. 20140131 12:45 38.4170 20.4802 5 4.4 11 69 173 8 85 72

20. 20140201 16:33 38.1730 20.3612 9 4.8 206 71 -152 6 68 99

21. 20140204 19:42 38.2850 20.3942 5 4.2 162 66 67 6 84 56

22. 20140206 19:21 38.1628 20.3795 19 4.4 20 72 -161 6 35 86

23. 20140207 03:26 38.3242 20.4410 3 3.9 181 70 81 7 49 98

24. 20140207 08:59 38.2328 20.4287 9 4.1 172 89 -176 8 68 57

25. 20140208 17:12 38.2507 20.4392 9 3.9 346 75 -157 6 59 93

26. 20140209 08:22 38.1812 20.3863 3 4.5 321 55 30 6 76 75

27. 20140212 10:34 38.1655 20.3538 11 4.5 190 83 -176 6 65 28

28. 20140214 03:38 38.1853 20.3498 7 4.7 112 57 -5 7 65 79

29. 20140215 07:31 38.2247 20.3538 5 4.7 146 77 67 6 67 100

30. 20140305 12:49 38.0780 20.3092 1 4.8 203 75 114 6 69 98

31. 20140310 23:27 38.2222 20.3342 7 4.0 119 72 53 6 75 89

Table S2 Corner points of the finite faults as parameterized in the slip inversions

Upper left Upper right * Bottom left Bottom right

January 26, 2014

20 km ×20 km

Depth: 0.5-30 km

38.1390 °N

20.3280 °E

38.3932

20.4453

38.1230

20.3838

38.3771

20.5013

February 3, 2014

segment 1

24 km ×10 km

Depth: 0.5-10.5 km

38.3460 °N

20.4270 °E

38.1296

20.4270

38.3460

20.4190

38.1296

20.4190

segment 2

20 km ×10 km

Depth: 0.5-10.2 km

38.1352 °N

20.3226 °E

38.2879

20.4477

38.1235

20.3434

38.2772

20.4716

* Direction along the fault strike

Table S3 Parameters of the principal stress axes based on the inversion from aftershocks (see

also Figure 7 and S7).

Azimuth (°) Plunge (°)

σ1 248 7

σ2 63* 83 *

σ3 158* 1 *

Shape ratio 0.87

* Highly uncertain, see Figure S7c

Supplementary Figures

Figure S1 Stations used in the waveform inversions. Squares and triangles indicate broadband

and strong motion stations, respectively. Blue triangles denote stations without accurate

timing.

Figure S2 Displacement waveform fit for the CMT calculations (0.05-0.08 Hz). The observed

and synthetic waveforms are shown in black and red, respectively, for a) the 1st and b) the 2

nd

event.

Figure S3 Final slip distribution on faults, superimposed by the slip-rate functions plotted for

all subfaults (left), and the time of occurrence of slip-rate maximum (right). a) 1st event, b) 2

nd

event – segments 1 and 2. Stars denote the corresponding hypocenters (Table 1) projected on

the respective fault planes as in Figures 4 and 5. The slip-rate range on vertical axes of small

figures is 0.2 m/s and 0.5 m/s in panels a) and b), respectively. The slip-rate range on

horizontal axes of small figures is 12 s and 10 s in panels a) and b), respectively.

Figure S4 Displacement waveform fit for slip inversion (0.05-0.2 Hz). The observed and

synthetic waveforms are shown in black and red, respectively. Peak observed displacement

appears to the right. a) 1st event, b) 2

nd event – both segments 1 and 2 considered in the

inversion, c) 2nd

event – only segment 1 considered in the inversion. The Z-component of

DMLN station was excluded from inversion due to disturbed record.

Figure S5 Apparent source time functions of the 1st event, derived by the EGF method.

Figure S6 Static surface displacements, calculated from the seismically derived slip model

and applying forward modeling, of the February 3, 2014 event, using the two segments

proposed by Boncori et al. (2015). The star marks the epicenter location. The black arrow

vectors denote a) horizontal and b) vertical motion. Panels c) and d) show the same for the

single-segment model, basically keeping all major features of the displacement field.

Figure S7 Stress field derived from the aftershocks. a) P-T axes of the aftershocks and the

principal stress axes. b) Mohr’s diagram with projected aftershocks. c) Principal stress axes

and their uncertainty. d) Uncertainty of the stress-shape ratio.