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Affected strata with deformation structures generated by co-seismic activity of M≥5, in San Pedro El Alto, Acambay graben. Load-flame structures formed by liquefaction of silt, which is introduced into the upper layers. Pseudonodules formed by density difference between volcanic ash and sand. (Intensity VII on ESI 2007 scale). See related article by Velázquez-Bucio y Garduño-Monroy in this issue.