Deformed Mudcracks

Deformed mudcracks in Precambrian metasedimentary strata, Ellis, Idaho. The principal maximum extension direction is indicated by the arrows; note that this is perpendicular to joints and veins and parallel to the average long axis of the mudcrack poplygons. The original mudcracks could be circumscribed by circles; the deformed mudcracks can be circumscribed by ellipses. Photo credit: Roy W. Schlische.