Decreasing magmatic footprints of individual volcanoes in a waning basaltic field

Abstract

[1] The distribution and characteristics of individual basaltic volcanoes in the waning Southwestern Nevada Volcanic Field provide insight into the changing physical nature of magmatism and the controls on volcano location. During Pliocene-Pleistocene times the volumes of individual volcanoes have decreased by more than one order of magnitude, as have fissure lengths and inferred lava effusion rates. Eruptions evolved from Hawaiian-style eruptions with extensive lavas to eruptions characterized by small pulses of lava and Strombolian to violent Strombolian mechanisms. These trends indicate progressively decreasing partial melting and length scales, or magmatic footprints, of mantle source zones for individual volcanoes. The location of each volcano is determined by the location of its magmatic footprint at depth, and only by shallow structural and topographic features that are within that footprint. The locations of future volcanoes in a waning system are less likely to be determined by large-scale topography or structures than were older, larger volume volcanoes.

Relationships between volcano distribution, crustal structure, and P-wave tomography: an example from the Abu Monogenetic Volcano Group, SW Japan

“…4b also shows the eruption rate of basalt decreased somewhat at this time. Although formation of both basaltic and andesitic volcanoes increased after about 0.2 Ma, the volume of individual basaltic eruptions decreased, a feature seen in other monogenetic volcanic fields (e.g., Valentine and Perry 2006). Hence the volumetric magma eruption rate did not increase significantly after about 0.2 Ma (Fig.…”

“…Generally, volcanic fields consist of scattered monogenetic volcanoes, such as cinder cones, maars, tuff cones, tuff rings, small shield volcanoes, lava domes and attendant lava flows Valentine and Perry 2006), and are also called monogenetic volcano groups. The temporal and spatial distribution of monogenetic volcanoes and probability of future activity within monogenetic volcano groups have been studied with the goals of understanding the origins of these volcano groups, and forecasting potential future volcanic hazards (Scandone 1979;Connor and Hill 1995;Alberico et al 2002;Martin et al 2003;Valentine and Perry 2006;Alberico et al 2008). Here we investigate the Abu Monogenetic Volcano Group (AMVG), located in Southwest Japan, as a case study to consider the influences of magma generation and ascent processes upon the temporal-spatial distribution of monogenetic volcanoes.…”

Compositional and Mineralogical Effects on Ice Nucleation Activity of Volcanic Ash

“…The three remaining samples (ONW, PINW, and NIW) originate from fall deposits produced during the~77 ka Lathrop Wells eruption in the Southwestern Nevada Volcanic Field, USA. [47][48][49][50][51]. ONW represents oxidized scoria, PINW represents scoria containing accidental lithics, and NIW represents scoria with all lithics removed (Table S1).…”

An Overview of the Monogenetic Volcanic Fields of the Western Pannonian Basin: Their Field Characteristics and Outlook for Future Research from a Global Perspective

“…The WPB's volcanic fields are relatively welldescribed from a physical volcanology point of view. However, new globally significant research has recently identified the following as the critical parameters that strongly influencing the basic characteristics of the resulting volcanic fields: the interplay between the external and internal forcing of the eruption styles of small-volume mafic volcanoes; the influence of long term environmental changes on the variations of the dominant eruption styles in the evolution of the volcanic field; and the long term fluctuation of magmatic flux and output rates (Valentine & Perry, 2006;Valentine & Keating, 2007;Valentine & Perry, 2007;Keating et al, 2008;Brenna et al, 2010;Genareau et al, 2010;Valentine & Hirano, 2010;Brenna et al, 2011). An application of these new results for WPB volcanism could lead to a better understanding of the eruption history of the individual monogenetic volcanoes of WPB and could allow them to be comparedto similar volcanoes worldwide.…”