The subduction, the divergence and the earthquakes

Hamid Sadeghipour

                                                 05.05.2017

Last night, there was another moderate earthquake, 3.1 Richter in Sangsefid in Khorasan Province, Iran. We know that any phenomenon has several reason to make it to happen. What I mention is a complementary to other kind of analysis. When we look to natural map or google satellite map, me see for example, in the south west of Mashhad the mountain, I believe, is the Binalud. Binalud is like a ocean divergence basin. We can say the mountain is a part of an ancient ocean. Before it was ocean basin, but by subduction, it changed direction and became a slope. The sedimentation as a cover went to south east of Mashhad and some part of this cover when to north the create a wall before the region of Sangsefid. This subduction made movements along and in the east of this sticken region another part created another wall. During thousands of years the rain water was trapped in the region between these walls. Geologically, the mountain was a slope in the beggining. But, now a washed slope becoming Sangsefid. Before creation of divergence, under the ocean basin was rivers sedimentations as during that time we had much more rain. You can see the land piece in the vicinity of Sangsefid and in the south of it, has a fault going down into the soil. Water has washed underground and the land went down. Two co-seismic wrapped interferometric maps from observation and DInSAR study published by EMSC- European seismological society, you can find on their site, show a concentric circles. If after creation of the fault beside the Sangsefid, rain water washed the layer of divergence effects, we can see under basin. Underground wash and taking away some part of soil texture in this region, create some sandy soil. By the action of the planets and magmatic up and down you can have some liquefaction. What I propose is to dig deep wells and fill with armed concrete. It might reinforce the soil. If possible dig some wells besides with the tubes having holes to allow flowing of   low grade concrete and fill them with this low grade concrete   and using no armor. It is it the job of civil engineers and computations. To prevent the earthquakes in other regions throughout the world, you can have the same recommendation according to morphology of the region.