a)
b)
Figure A1
13û 267û
ELEN
TPCH
GUAT
TEGU
PF
15 mm/yr
Guatemala
Honduras
Salvador
ITRF2000 reference frame
268û 269û 270û 271û 272û 273û
14û 15û 16 17û 18
MF
Belize
SSIA
Mexico
FORT KOUR CRO1
BOGT AOML PIE1 ENG1
THTI MAUI
NOUM
267˚ 268˚ 269˚ 270˚ 271˚ 272˚ 273˚
13˚
14˚
15˚
16˚
17˚
18˚
15 mm/yr
ITRF2000 reference frame
7
6
5
4
3
2
1
0
-1
0 50 100 150 200
η=10 18 η=10 19
η=10 20
η =10 21
Cumulative postseismic displacement (cm)
Distance to Motagua fault (km)
30 yr 23 yr 27 yr
23 yr
27-30 yr
Pa.s Pa.s
Pa.s
Pa.s
Figure A2
273°
265° 266° 267° 268° 269° 270° 271° 272°
12°
13°
14°
15°
16°
17°
18°
19°
20°
21°
22°
0
265° 266° 267° 268° 269° 270° 271° 272° 273°
265° 266° 267° 268° 269° 270° 271° 272° 273°
12°
13°
14°
15°
16°
17°
18°
19°
20°
21°
22°
0
265° 266° 267° 268° 269° 270° 271° 272° 273°
0 0.5 1
5 mm/yr
Mexico
Guatemala
Honduras
El Salvador Forward velocities
Caribbean plate reference frame
0 0.5 1
5 mm/yr
χ
2= 0.2
Mexico
Guatemala
Honduras Residual velocities
Caribbean plate reference frame
0 0.5 1
5 mm/yr
Mexico
Guatemala
Honduras
El Salvador Forward velocities
Caribbean plate reference frame
0 0.5 1
5 mm/yr
χ
2= 0.6
Mexico
Guatemala
Honduras Residual velocities
Caribbean plate reference frame
Φ coupling 1
0
1
1 0
0
0.5
1
0
1
1 0
0
0 1
1
1
Φ coupling Φ coupling
Φ coupling 0 km
0 km 25 km
50 km 90 km
0 km 0 km 25 km
50 km 90 km
0 km 0 km 25 km
50 km 90 km
0 km 0 km 25 km
50 km 90 km
El Salvador El Salvador
MFc, Φ=0.38 MFe, Φ=0.9 MFc, Φ=0.38 MFe, Φ=0.9