Ground crack, VLF measurement, and sample vesicularity data for the June 2007 Father's Day eruption, Kīlauea Volcano

An intrusion into Kīlauea’s upper East Rift Zone during June 17–19, 2007, during the 1983–2018 Pu‘u‘ō‘ō eruption, led to widespread ground cracking and a small (~1,525 m3) eruption on the northeast flank of the Kānenuiohamo cone, about 6 km upslope from the Pu‘u‘ō‘ō vent. Electromagnetic profiles using the very-low-frequency (VLF) technique (McNeill and Labson, 1991) were measured along transects spanning the dike trace, and zones of ground cracking related to the intrusion were mapped. The locations of crack zones and the VLF receiver measurements suggest that the Father’s Day dike splayed as it approached the surface, dividing into four segments—one between Pauahi Crater and Pu‘uhuluhulu and three en echelon segments near Kānenuiohamo. The dike did not extend appreciably northeastward beyond the eruption site. This data release comprises four datasets, including: (1) the location, trend, width, and opening direction of a subset of new ground cracks formed during the June 2007 Father's Day dike intrusion and eruption; (2) line lengths between sets of nails spanning ground cracks at five "crack stations" in Nāpau Crater, installed in 1997 to monitor change; (3) the density and vesicularity of selected lava and tephra samples collected from the June 2007 Father's Day eruption site; and (4) induced electromagnetic field measurements collected using a Geonics Limited EM16 very low frequency (VLF) electromagnetic receiver along eight transects across and perpendicular to the presumed trace of the 2007 Father's Day dike.