damavand is a large dormant stratovolcano in the alborz mountains of northern iran located in one of the most populous provinces, which could be adversely affected by tephra fall from damavand. the youngest known eruption is a lava flow on the western flanks with an age of 7.3 ka. the volcanic products are predominantly porphyritic trachyandesite. three major young pumice deposits, named here a...

We discuss maar-diatremes and calderas as end-members on a spectrum of negative volcanic landforms (depressions) produced by explosive eruptions (note—we focus on calderas formed during explosive eruptions, recognizing that some caldera types are not related to such activity). The former are dominated by ejection of material during numerous discrete phreatomagmatic explosions, brecciation, and ...

Magmatic intrusions and volcanic eruptions are intimately related phenomena. Shallow magma intrusion builds subsurface reservoirs that are drained by volcanic eruptions. Thus, the long-held view is that intrusions must precede and feed eruptions. Here we show that explosive eruptions can also cause magma intrusion. We provide an account of a rapidly emplaced laccolith during the 2011 rhyolite e...

[1] Models of the early stages of basaltic eruptions beneath temperate glaciers are presented that consider the evolving sizes of volcanic edifices emplaced within subglacial cavities. The cavity size reflects the competing effects of enlargement by melting and closure by downward ductile deformation of the ice roof, which occurs when the cavity pressure is less than glaciostatic due to meltwat...

Damavand is a large dormant stratovolcano in the Alborz Mountains of northern Iran located in one of the most populous provinces, which could be adversely affected by tephra fall from Damavand. The youngest known eruption is a lava flow on the western flanks with an age of 7.3 ka. The volcanic products are predominantly porphyritic trachyandesite. Three major young pumice deposits, named here a...

Tephra layers in marine sediment cores from scientific ocean drilling largely record high-magnitude silicic explosive eruptions in the Japan arc for up to the last 20 million years. Analysis of the thickness variation with distance of 180 tephra layers from a global data set suggests that the majority of the visible tephra layers used in this study are the products of caldera-forming eruptions ...

[1] A mechanism for explosive volcanic eruptions based on multicomponent phase equilibria modelling of four explosive volcanic systems is proposed. In each system, either isochoric or isobaric crystallization, where either crystals or crystals and exsolved fluid are chemically fractionated from melt, leads inevitably to near-solidus dynamical instability culminating in violent explosive eruptio...

Explosive volcanic eruptions, potentially involving large amounts of magmatic and entrained water, are thought to have been very important in the Noachian and Hesperian periods earlier in Mars history, and basaltic plinian eruptions are likely to have occurred throughout martian history. Previous treatments of explosive volcanic plumes on Mars have simply extrapolated plume models for the Earth...

Phonolitic eruptions can erupt either effusively or explosively, and in some cases develop highly energetic events such as caldera-forming eruptions. However, the mechanisms that control the eruptive behaviour of such compositions are not well understood. By combining pre-eruptive data of well studied phonolitic eruptions we show that the explosive-effusive style of the phonolitic magma is cont...