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(A)(B)Focus area of Figure 8bPavement levelprior to 22 February2011 eventExposedfoundation▲▲Figure 8. Duplex housing complex: A) looking north at center building, and B) close-up of ground settlement next to center building(16 March 2011; S43.52399 E172.64417).Structure shownin Figure 11Structure shownin Figure 12Observed liquefaction features▲▲Figure 9. Two-story building that underwent liquefactioninducedpunching movements (7 March 2011; S43.52506E172.64176).tered, which is consistent with the pronounced settlementbeneath the walls along the perimeter of the building.Differential Settlement and Sliding—Armagh-MadrasAreaFarther to the south, at the intersection of Madras and Armaghstreets, several buildings were affected by severe liquefactionthat induced significant differential settlements or lateralmovements. At this location, the liquefaction was manifestedby a well-defined, narrow zone of surface cracks, fissures, anddepression of the ground surface about 50 m wide, as well aswater and sand ejecta (Figure 10). This zone stretches from theAvon River to the north toward the buildings affected by thisliquefaction feature, shown in the background of Figure 10 tothe south. Traces of liquefaction were evident further to thesouth of these buildings.▲ ▲ Figure 10. Relatively narrow liquefaction-induced featurethat traverses parking lot northeast of the intersection of Madrasand Armagh streets (24 March 2011; S43.52842 E172.64308).The building shown in Figure 11 is a three-story structureon shallow foundations that settled substantially at its front,resulting in large differential settlements that tilted the buildingabout 2 degrees. The building was also uniformly displacedlaterally approximately 15 cm toward the area of significantliquefaction near the front of the building (i.e., to the north).There was a large volume of sand ejecta at the front part of thebuilding with ground tension cracks propagating east of thebuilding and in the rear car-park that were consistent with thelateral movement of the building toward the north.The building shown in Figure 12 is immediately across thestreet to the north. It is a six-story building on isolated footingswith tie beams and perimeter grade beam. The isolated footingsare 2.4 m × 2.4 m and 0.6 m deep. Figure 12 shows the view ofthe building looking toward the west and indicates total settlementsmeasured relative to the building to its north, which did900 Seismological Research Letters Volume 82, Number 6 November/December 2011