The idea is not bad.

    But can be subduction with such irregularities?

Benioff zone is very chaotic under South America.

We can avoid this place do not subduction but collision?

This is a simpler explanation?

 Our earthquakes occur in the lithosphfere, not in the Benioff zone.

Maybe the irregularities are in the Nazca plate, like almost islands, next to the subduction zone. What do you think?

May be, but I must to see map and section for create some opinion.

What deep have your earthquakes?

Hello to Everybody!

If you decided to discuss the subduction zones under the South American plate, including  the Benioff zones and the Nazca plate, please, allow me to pay you attention at one very interesting natural fact  that has no explanation yet.

It is revelad recently (attachment) that the southern boundary of the Nazca plate is magnetically conjugate with the northern boundaries of the Cococ and Carribian  plates. The angle of the subductions here is of about  45 degrees, that is exactly the angle of the geomagnetic  Inclination here.  This gives a hint  that  the earthquakes occur along the geomagnetic lines loaned into the crust, that results in the appearing of the subduction line. Attachment is in Russin, but figure captions are in English, thus, are understandable. 

Galina

Thank you very much!

Regards!

 V. M. Anokhin, our earthquakes occur mostly from 30 to 50 km app.

Thanks, Marcelo, it is not very deep.

It is near  the crust sole in this area?

Dear All,

The South American Plate is subdivided by some major transcurrent faults, they are orthogonal to the subduction line. This is clearly revealed by the earthquakes. I think the subduction line is also subdivided accordingly. I just published some maps to show the distribution of the earthquakes in South America.

Dear Falih Mahdi Daim,

I d like to look your maps, send me reference, plese.

Dear Mr. Anokhin,

The maps are in a short presentation in my profile in this site.

Regards.

Dr. Falih Daim

 Dear Dr. Falih Daim,

Thanks for maps.  

I see on these maps are not inclined (45 deg.) subduction zone, and a series of vertical deep-section zones that are submerged beneath South America partly in the form of steps.

Your opinion?