Linking distal volcaniclastic sedimentation and stratigraphy with the development of Ruapehu volcano, New Zealand

Abstract

Long-lived stratovolcanoes are often characterized by cycles that include pulses of explosive and effusive eruptive activity, periodic flank collapses, and long periods of eruptive quiescence. Reconstructing these solely from exposures on volcanic edifices is difficult because deposits are dominantly from comparatively recent reconstruction episodes, while older sequences are buried or have long been eroded. Long-runout mass-flow deposits, on the other hand, offer insights into the older eruptive history and long-term eruptive behavior of composite volcanoes. At Mt. Ruapehu, New Zealand, 40 Ar/ 39 Ar dating of lava clasts within distal mass-flow sequences, combined with new mapping and sedimentological descriptions, reveal three hitherto unknown eruptive episodes of the volcano and extend its minimum age to at least 340 ka. Plinian to subplinian eruptions were followed by periods of subdued volcanic activity. Voluminous (>1 km 3 ) inter-eruptive flank failures were precursors to major reconstruction episodes, associated with numerous syneruptive mass flows emplaced up to 90 km from the volcano. Syn-eruptive collapse triggered large plinian eruptions associated with pyroclastic density currents. Rapid ring-plain aggradation dominated during periods of subdued volcanic activity when intensive edifice erosion induced frequent inter-eruptive lahars.

Sedimentological and petrographic evolution of a fluvio‐lacustrine environment during the onset of volcanism: Volcanically‐induced forcing of sedimentation and environmental responses

“…However, as shown in the Cañadón Asfalto Basin, the episodically short‐lived explosive events that characterize explosive volcanism are able to inundate proximal environments with huge volumes of loose volcaniclastic sediments, transporting them across a ‘source to sink’ system for tens of kilometres. Moreover, volcaniclastic sediments can be transported up to hundreds of kilometres relatively independent of the water availability and drainage patterns (Segschneider et al ., ; Sohn et al ., ; Manville et al ., , ; De Rosa et al ., ; Umazano et al ., ; Kataoka et al ., ; Eliwa et al ., ; Kataoka, ; Khalaf, ; Cuitiño & Scasso, ; van Gorp et al ., ; Gihm & Hwang, ; Tost & Cronin, ; Di Capua & Groppelli, 2016a; Di Capua et al ., ).…”

The geomagnetic field intensity in New Zealand: palaeointensities from Holocene lava flows of the Tongariro Volcanic Centre

“…The Tongariro Volcanic Centre (TgVC) is a complex of several andesitic to dacitic composite volcanoes, located at the southern extremity of the Taupo Volcanic Zone, with effusive activity extending back at least 350 kyr (Tost & Cronin 2015) and lasting into recent centuries (e.g. Hobden et al 1996;Gamble et al 2003;Eaves et al 2015;Conway et al 2016;Greve et al 2016).…”

Quantitative geometric description of fracture systems in an andesite lava flow using terrestrial laser scanner data

“…Ruapehu may be as old as 340 kyr (Tost & Cronin, 2015), but the exposed edifice was mainly constructed by basaltic-andesite to dacite lava effusion in the last 200 kyr (Gamble et al, 2003;Conway et al, 2016). Ruapehu is primarily composed of blocky lava flows and autobreccias, with 54-65 wt.…”