Geological setting of the 1987 Edgecumbe earthquake, New Zealand

Evaluation of seismic hazard in the Rangitaiki Plains, New Zealand

“…1987). Although no further data are available, there is a possibility that the strike-slip faults may be less active near their northern terminations than further south, and the recurrence interval may be rather longer than previously Nairn & Beanland (1989) estimated. Typical single-event displacements on these faults may be associated with earthquakes in the range M 7.0-7.5 (Smith & Berryman 1986;Raub et al 1987), significantly larger than those associated with the normal faults of the Whakatane Graben.…”

“…Staff ofNZ. Department of Scientific and Industrial Research (1987) and Nairn & Beanland (1989) provide a more detailed setting. Nairn & Beanland also discuss the evidence for recurrence intervals of rupture on some of the active faults within and at the margins of the plains.…”

“…The Rangitaiki Plains is primarily the surface expression of the Whakatane Graben, the northeast-trending rift at the eastern margin of the CVR (Nairn & Beanland 1989). The graben is about 15 kIn wide at the coastline, has bounding faults on the eastern and western margins, and tends to narrow to the southwest toward the recently active Okataina Volcanic Centre.…”

A “least complex” dynamic model for late Cenozoic volcanism in the North Island, New Zealand

“…"Taupo Volcanic Zone" is best retained for the youngest of these intervals, but the definition of its precise geographic and time limits, and the naming of earlier zones (possibly using Ballance's (1976) term "Tauranga" as one), best awaits the results of current intensive research within the whole region. Figure 2 References for the ages shown, not given in the main text, are Whakamarama (Houghton et al 1991), Mangakino (Pringle et al 1992), Titiraupenga and Tauhara (Stipp 1968), Marshall Ignimbrites and Taupo ), Tongariro, Ngauruhoe, Ruapehu, Mt Edgecumbe, and White Island (Cole et al 1986a, b), Maroa and the Whakamaru Ignimbrites ), Okataina (Kohn 1986;Nairn & Beanland 1989), and Whale Island (Duncan 1970). has tended to move laterally with time, sinistrally when viewed from the subduction trough (Fig. 3); (4) andesitic chain-the southern end of a 2500 km active chain, from White Island through the Rumbles Seamounts and Kermadec Islands to Tonga (Fig.…”

A radiocarbon age determination for Mount Edgecumbe (Putauaki) volcano, Bay of Plenty, New Zealand

“…1). It is situated on the southeastern flank of the Whakatane Graben, which dominates the geological structure of the Bay of Plenty region (Nairn & Beanland 1989).…”