We present the up-to-date seismicity associated with the Avaj fault system as a series of space-time sections. The aim is to reveal the hidden orders and to facilitate prompt interpretation. The earthquake data is obtained from the IRSC and the ISC databases every minute. With new earthquakes the figures and maps are updated immediately; otherwise, they are regenerated every hour. The following points should be considered regarding the images.
- There are 8 figures showing time-space sections of seismicity for different periods. Earthquakes are projected on the line segments that represent the Avaj system.
- The yellow line segments, ‘SE-NW’, on the maps show the section. Earthquakes within a 20 km range are projected in the section.
- For each figure X, there are 3 associated illustrations with a corresponding period. Xa shows the seismicity for the whole region, while Xb displays the events in the window around the section. Figure Xc shows the depth distribution of events along the section. Their links are given below each figure.
- The thick red line segment that is labeled N on the maps and also along the right axis of each figure represents a seismic gap from the neighboring Ipak Fault System.
- The thick magenta line segments along the left axis or within the figures, (230-250 km and 250-280 km), in turn, show the projection of part of the 01 September 1962 (M~7.0) (Ambraseys and Melville, 2005) and the surface rupture of the 22 June 2002 (Mw 6.5) earthquakes (Mahdavifar et al., 2006).
- The pale-green polygon next to gap C shows the extents of Tehran.
- The earthquake data for the post-2006 period is obtained from the IRSC catalog, while the ISC database is the data source for earlier times.
Acknowledgment
The earthquake data for this project is obtained from (i) the “Iranian Seismological Center” (IRSC) of the Institute of Geophysics, University of Tehran and (ii) the International Seismological Center (ISC). We appreciate these institutions for the release of their products to the public. The figures are produced by using the “Generic Mapping Tool” (GMT) and we thank the developers of the software (Wessel et al., 2013).
References
- Ambraseys NN, Melville CP. A History of Persian Earthquakes. Cambridge university press; 2005.
- Mahdavifar MR, Solaymani S, Jafari MK. Landslides triggered by the Avaj, Iran earthquake of June 22, 2002. Engineering geology. 2006;86:166–182.
- Wessel P, Smith WH, Scharroo R, Luis J, Wobbe F. Generic mapping tools: improved version released. Eos, Transactions American Geophysical Union. 2013;94:409–410.