1. José Faustino Blanco Chía National University of Colombia Geosciences Department

2. Issue The principal goal is to find the velocity structure in Colombia to improve the location of local earthquakes.

3. Data The data come from the Colombian National Seismic Network (RSNC), from 1993 to present. Most of the data come from weak earthquakes, M L <5.0. Waveforms recorded using EARTHWORM. Earthquakes located using SEISAN. One velocity model for the whole country.

4. Colombian National Seismic Network 1993 - 2000, short period sensors. 2001 - 2007, one broad-band station 2008-2013, 31 new broad band stations

5. Tectonic context

6. Geologic terrains in Colombia

7. Colombia Seismological Stations

8. Seismicity 1993-2012 RSNC

10. Shallow Seismicity 1993 - 2012 RSNC

11. Seismicity

12. Current velocity model

13. Data

14. Data 1993-2012

15. Shallow data 1993-2012

16. Parameters of choosen events Shallow seismicity < 50 km GAP < 180 Minimum number stations 6 Minumum Local Magnitude 2.0 Total seismos selected 2879

17. Questions How do we use the data from earthquake nests Bucaramanga, for example? Is it a good idea to use only shallow seismicity? Is it a good idea to use teleseismic data?

18. THANKS!!!