Journal Articles
Permanent URI for this collectionhttps://mro.massey.ac.nz/handle/10179/7915
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Item Pitfalls in erosion level calculation based on remnants of maar and diatreme volcanoes (Les pièges de la reconstitution des topographies d'érosion initiales fondée sur les vestiges des maars et diatrèmes volcaniques)(Massey University., 2007-01-01) Nemeth, Karoly; Martin, Ulrike; Csillag, GaborAbstract Erosion estimates based on geometrical dimension measurements of eroded maar/diatreme volcanoes are useful methods to determine syn-volcanic surface level and syn-volcanic bedrock stratigraphy. However, such considerations on volcanic architecture should only be employed as a first-order approach to determine the state of erosion. We demonstrate, on both young and eroded maar/diatreme volcanoes, that establishing the volcanic facies architecture gives vital information on the environment in which the volcano erupted. In 'soft' rocks, maar volcanoes are broad and underlain by 'champagne glass'-shaped diatremes. In contrast, the crater wall of maar volcanoes that erupted through "hard rocks" will be steep, filled with lacustrine volcaniclastic deposits and underlain by deep diatremes. Résumé L'estimation de l'érosion fondée sur la géométrie des volcans de type maar-diatrème est une méthode applicable à la reconstruction de la surface syn-volcanique et de la stratigraphie de la série sous-jacente. Toutefois les considérations relatives à l'architecture volcanique doivent seulement être utilisées comme une première approche pour déterminer le niveau initial de la surface aujourd'hui érodée. Nous démontrons que la détermination des faciès volcaniques, tant dans les maars-diatrèmes récents que dans les systèmes érodés de ce type, donne des informations fondamentales sur la nature des roches encaissantes au sein desquelles l'éruption volcanique s'est produite. Dans les roches encaissantes meubles, les maars sont larges avec un diatrème sous-jacent en forme de « coupe de champagne». Au contraire, au sein de roches plus résistantes, les cratères de maars sont entourés de parois raides et bien souvent remplis de dépôts lacustres d'origine volcanoclastique qui masquent des diatrèmes profonds.Item Understanding the evolution of maar craters(Massey University., 2006-01-01) Haller, Miguel J.; de Wall, Helga; Martin, Ulrike; Nemeth, KarolyNo abstract availableItem MAAR conference in Hungary(Massey University., 2005-01-01) Martin, Ulrike; Nemeth, KarolyNo abstract availableItem Mio/Pliocene phreatomagmatic volcanism in the Western Pannonian Basin(Massey University., 2004-01-01) Martin, Ulrike; Nemeth, KarolyNo abstract availableItem Large hydrovolcanic field in the Pannonian Basin: general characteristics of the Bakony- Balaton Highland Volcanic Field, Hungary.(Massey University., 1999-01-01) Nemeth, Karoly; Martin, UlrikeNo abstract availableItem Pliocene crater lake deposits and soft sediment deformation structures associated with a phreatomagmatic volcano, Pula maar, western Hungary.(Massey University., 2002-01-01) Nemeth, Karoly; Martin, Ulrike; Csillag, GaborNo abstract availableItem Long-term erosion-rate calculation from the Waipiata Volcanic Field (New Zealand) based on erosion remnants of scoria cones, tuff rings and maars.(Massey University., 2001-01-01) Nemeth, KarolyErosion of scoria cones, tuff rings and maars follows a general evolution. Identification of distribution patterns of preserved pyroclastic lithofacies of scoria cones, tuff rings and maars allows an estimation of "depth" of erosion since volcanism ceased. Study of the accidental lithic clast population in pyroclastic rocks of erosion remnants of basaltic maar/tuff ring volcanoes of the Miocene Waipiata Volcanic Field (WVF), New Zealand is demonstrated to be a good tool re-establish the "missing" stratigraphy and estimate the erosion since volcanism. An example from a subsequently tilted erosion remnant of the Swinburn multivent volcanic complex (WVF) demonstrates the importance of tilting as an effect of erosion rate calculations. The 3 vents of the WVF investigated from New Zealand suggest a range of erosion rates from 3.75 to 46 m/My depending on 1) the position of the remnant in comparison to uplifted fault/fold blocks; and, 2) considering or neglecting the effect of subsequent tilting on erosion rate calculations.Item Depositional record of a Pliocene nested multivent maar complex at Fekete-hegy, Pannonian Basin, western Hungary.(Massey University., 2002-01-01) Martin, Ulrike; Nemeth, Karoly; Auer, Andreas; Breitkreutz, Christoph; Csillag, GaborNo abstract available