Qu'est-ce (qui) est pyroclastic - définition

ROCKS COMPOSED SOLELY OR PRIMARILY OF FRAGMENTS DERIVED FROM EXPLOSIVE VOLCANIC ACTIVITY

Pyroclastic; Pyroclastic rocks; Pyroclastics; Pyroclastic material; Pyroclastic deposit

pyroclastics

pyroclastic material.

nuee ardente

FAST-MOVING CONCENTRATED CURRENT OF HOT GAS AND VOLCANIC MATTER THAT MOVES AWAY FROM A VOLCANO

Pyroclastic flows; Pyroclastic Flow; Pyroclastic Eruption; Nuée ardente; Nuee ardente; Pyroclastic cloud; Nués ardentes; Pyroclasic flows; Pyroclastic density current; Ash flow; Nues ardentes; Nuees ardentes; Pyroclastic Flows; Stone wind; Nuée Ardente; Glowing Cloud; Nuées ardentes; Nuee Ardente; Pyroclastic eruption; Pyroclastic current; Pyroclastic Current; Pyroclastic Stream; Pyroclastic stream; Nue ardente; Ashflows; Ashflow

[?nj?e. ?:'d? uee ardentet]

¦ noun Geology an incandescent cloud of gas, ash, and lava fragments ejected from a volcano, typically as part of a pyroclastic flow.

Origin

Fr., lit. 'burning cloud'.

Pyroclastic fall

DEPOSIT OF MATERIAL EJECTED FROM A VOLCANIC ERUPTION

Pyroclastic air fall

A pyroclastic fall is a uniform deposit of material which has been ejected from a volcanic eruption or plume such as an ash fall or tuff. Pyroclastic air fall deposits are a result of:

https://en.wikipedia.org/wiki/Pyroclastic_fall

Wikipédia

Pyroclastic rock

Pyroclastic rocks (derived from the Greek: πῦρ, meaning fire; and κλαστός, meaning broken) are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroclasts. Pyroclastic rocks are a type of volcaniclastic deposit, which are deposits made predominantly of volcanic particles. 'Phreatic' pyroclastic deposits are a variety of pyroclastic rock that forms from volcanic steam explosions and they are entirely made of accidental clasts. 'Phreatomagmatic' pyroclastic deposits are formed from explosive interaction of magma with groundwater.

Unconsolidated accumulations of pyroclasts are described as tephra. Tephra may become lithified to a pyroclastic rock by cementation or chemical reactions as the result of the passage of hot gases (fumarolic alteration) or groundwater (e.g. hydrothermal alteration and diagenesis) and burial, or, if it is emplaced at temperatures so hot that the soft glassy pyroclasts stick together at point contacts, and deform: this is known as welding.

One of the most spectacular types of pyroclastic deposit is an ignimbrite, which is the deposit of a ground-hugging pumiceous pyroclastic density current (a rapidly flowing hot suspension of pyroclasts in gas). Ignimbrites may be loose deposits or solid rock, and they can bury entire landscapes. An individual ignimbrite can exceed 1000 km³ in volume, can cover 20,000 km² of land, and may exceed 1 km in thickness, for example where it is ponded within a volcanic caldera.

https://en.wikipedia.org/wiki/Pyroclastic rock

Exemples de prononciation pour pyroclastic

1. a huge pyroclastic cloud of debris came boiling up Greenwich Street toward us.

Wisdom _ Stephen Hall _ Talks at Google

Exemples du corpus de texte pour pyroclastic

1. "Army personnel have seen pyroclastic material, burning material," Miguel Munoz of the government‘s National Emergency Office said.

2. A pyroclastic flow – a fast–moving burst of blistering gases and rock fragments –– remains a main concern.

3. The main dangers at Merapi are fast–moving bursts of blistering gases and rock fragments called pyroclastic flow.

4. The main dangers at Merapi are fast–moving bursts of hot gases and rock fragments called pyroclastic flow.

5. Scientists have warned that, once the dome collapses, pyroclastic flows can ensue and last for weeks or months.