Attention Deficit Disorder Prosthetic Memory Program

Tephra

ADDPMP675

Tephra is unconsolidated pyroclastic material produced by a volcanic eruption. It consists of a variety of materials, typically glassy particles formed by the cooling of droplets of magma, which may be vesicular, solid or flake-like, and a varying proportions of crystalline and mineral components originating from the mountain and the walls of the vent. As the particles fall to the ground, they are sorted to a certain extent by the wind and gravitational forces and form layers of unconsolidated material. The particles are further moved by ground surface or submarine water flow.

The distribution of tephra following an eruption usually involves the largest boulders falling to the ground quickest, therefore closest to the vent, while smaller fragments travel further – ash can often travel for thousands of miles, even circumglobal, as it can stay in the stratosphere for days to weeks following an eruption. When large amounts of tephra accumulate in the atmosphere from massive volcanic eruptions (or from a multitude of smaller eruptions occurring simultaneously), they can reflect light and heat from the sun back through the atmosphere, in some cases causing the temperature to drop, resulting in a temporary “volcanic winter”. The effects of acidic rain and snow, the precipitation caused by tephra discharges into the atmosphere, can be seen for years after the eruptions have stopped. Tephra eruptions can affect ecosystems across millions of square kilometres or even entire continents depending on the size of the eruption.

Tephra fragments are classified by size:

Ash – particles smaller than 2 mm (0.08 inches) in diameter
Lapilli or volcanic cinders – between 2 and 64 mm (0.08 and 2.5 inches) in diameter
Volcanic bombs or volcanic blocks – larger than 64 mm (2.5 inches) in diameter

Tephra - © Attention Deficit Disorder Prosthetic Memory Program
Tephra - © Attention Deficit Disorder Prosthetic Memory Program
Tephra - © Attention Deficit Disorder Prosthetic Memory Program
Tephra - © Attention Deficit Disorder Prosthetic Memory Program
Tonic immobility - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP286
Tonic immobility
Nasa Aerogel - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP151
Nasa Aerogel
Ulvetanna - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP101
Ulvetanna
Effects Of Psychoactive Drugs On Spiders - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP335
Effects Of Psychoactive Drugs On Spiders
Doomsday Clock - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP753
Doomsday Clock
Catwalk Fails - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP294
Catwalk Fails
Tempescope - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP328
Tempescope
Rap Snacks - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP639
Rap Snacks
Shock Diamond - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP758
Shock Diamond
Tabular Iceberg - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP540
Tabular Iceberg
Null Island - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP466
Null Island
Anthony Braxton's Composition 113 - © Attention Deficit Disorder Prosthetic Memory Program
ADDPMP112
Anthony Braxton's Composition 113

You are using an outdated browser.
Please upgrade your browser to improve your experience.