<P> Another feature to emerge from the dome was called the "fin" or "slab ." Approximately half the size of a football field, the large, cooled volcanic rock was being forced upward as quickly as 6 ft (2 m) per day . In mid-June 2006, the slab was crumbling in frequent rockfalls, although it was still being extruded . The height of the dome was 7,550 feet (2,300 m), still below the height reached in July 2005 when the whaleback collapsed . </P> <P> On October 22, 2006, at 3: 13 p.m. PST, a magnitude 3.5 earthquake broke loose Spine 7 . The collapse and avalanche of the lava dome sent an ash plume 2,000 feet (600 m) over the western rim of the crater; the ash plume then rapidly dissipated . </P> <P> On December 19, 2006, a large white plume of condensing steam was observed, leading some media people to assume there had been a small eruption . However, the Cascades Volcano Observatory of the USGS did not mention any significant ash plume . The volcano was in continuous eruption from October 2004, but this eruption consisted in large part of a gradual extrusion of lava forming a dome in the crater . </P> <P> On January 16, 2008, steam began seeping from a fracture on top of the lava dome . Associated seismic activity was the most noteworthy since 2004 . Scientists suspended activities in the crater and the mountain flanks, but the risk of a major eruption was deemed low . By the end of January, the eruption paused; no more lava was being extruded from the lava dome . On July 10, 2008, it was determined that the eruption had ended, after more than six months of no volcanic activity . </P>

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