The volcano ejected a minimum of 1.1 km3 of uncompacted tephra, which is equivalent to 0. 20-0.25 km3 of magma or solid rock.    From Wordnik.com.  [volcanic ash hazards and ways to minimize them] Reference

The type of dust that attracted the engineers to Hawaii is called "tephra," a fine, powder-like material that is ejected during a volcanic eruption.    From Wordnik.com.  [SPACE.com] Reference

tephra F is the most prominent and best-dated tephra.    From Wordnik.com.  [Tephras in Ecuador « Climate Audit] Reference

Volcanic tephra are widespread in northern Ecuador, but hard to find in southern Ecuador.    From Wordnik.com.  [Tephras in Ecuador « Climate Audit] Reference

Typical of tephra-fall deposits, the tephra thickness rapidly downwind from Mount St. Helens.    From Wordnik.com.  [volcanic ash hazards and ways to minimize them] Reference

Volcanoes add mass to the continents when magma produces lava flows, tephra, and volcanic ash.    From Wordnik.com.  [Formation of the Earth's crust] Reference

The tephra probably comes from the extinct volcanic area around Lake Gölcük, ca. 10 km north of the site.    From Wordnik.com.  [Interactive Dig Sagalassos - Near the Theater Report 5] Reference

You have to tease ring characteristics out by dendrochronology to known events hence the reason for the tephra paper.    From Wordnik.com.  [Graybill and Funkhouser [1993] on Bristlecones « Climate Audit] Reference

A volcano is generally a conical-shaped hill or mountain built by accumulations of lava flows, tephra, and volcanic ash.    From Wordnik.com.  [Volcano] Reference

Fluorine adhering to tephra of the 1970 Hekla eruption: Journal of Volcanology and Geothermal Research, v. 8, p. 251-266.    From Wordnik.com.  [Volcanic Ash -- Effects on Water Supply and Mitigation Strategies] Reference

The evidence from the stratified finds of Theran tephra and pumice at a number of Aegean sites supports a Late Minoan IA date.    From Wordnik.com.  [Picture 181 « Field Notes 2009: Weeks 3 & 4 « Interactive Dig Crete – Zominthos Project] Reference

Over the last 2 million years, volcanoes have been depositing lava, tephra, and ash in particular areas of the globe (Figure 2).    From Wordnik.com.  [Volcano] Reference

Volcanic activity commenced approximately 500,000 years ago and tephra deposits indicate a peak of activity 10,000-14,000 years ago.    From Wordnik.com.  [Tongariro National Park, New Zealand] Reference

They observe that these tephra cannot be correlated to any of the observable large tephra in northern Ecuador in the last 2000 years.    From Wordnik.com.  [Tephras in Ecuador « Climate Audit] Reference

Defoliation of trees may also occur, especially if there is a coarse component of ash-sized particles or larger tephra and during heavy ash fall.    From Wordnik.com.  [Volcanic Ash—Effects on Agriculture and Mitigation Strategies] Reference

The mixed geological composition of the dust and tephra, plus the carbon, are claimed to be evidence of the explosion of an "extra-terrestrial projectile.".    From Wordnik.com.  [Godzilla's Attacking Babylon!] Reference

Tungurahua and Sangay are both still active: Sangay regularly ejects hot rocks and tephra and has the one of the world's longest records of continuous volcanic activity.    From Wordnik.com.  [Sangay National Park, Ecuador] Reference

The most recent volcanic deposit proved to be Santorini tephra, making the Sagalassos area currently the most eastward one connected with this middle Bronze Age catastrophe.    From Wordnik.com.  [Interactive Dig Sagalassos 2003 - Survey Conclusions] Reference

So, some of the evidence may point to a volcanic eruption, while there is no evidence that unequivocally necessitates an extra-terrestrial cause for the dust and tephra layer.    From Wordnik.com.  [Godzilla's Attacking Babylon!] Reference

In contrast to the eastern section of the Quarter, the mother rock turned out to be not the expected ophiolithic melange and weathered clays, but rather weathered volcanic tephra.    From Wordnik.com.  [Interactive Dig Sagalassos - Near the Theater Report 5] Reference

I hope it is just steam and gas from under some hot cinder or tephra.    From Wordnik.com.  [ScienceBlogs Channel : Life Science] Reference

Pinatubo from 1991 Apr 2 to 1991 Sep 2 was a VEI of 6 with tephra volume of 1. 1×10.    From Wordnik.com.  [RealClimate] Reference

Krakatau in 1883 was also a VEI of 6, but had roughly twice the tephra volume at 2. 0×10.    From Wordnik.com.  [RealClimate] Reference

Elevated SO2 and some tephra from Halema ` uma ` u vent; elevated SO2 from Pu ` u ` O ` o vent; lava in tubes to ocean.    From Wordnik.com. Reference

They determined this by looking at the tephra deposits near the vents and compared them to the record at Paricutin in Mexico.    From Wordnik.com.  [ScienceBlogs Channel : Physical Science] Reference

This morning's tephra collection yielded a small amount of ash; gas-rushing sounds were also heard during the morning routine.    From Wordnik.com. Reference

VEI is a base 10 logarithmic scale for measuring explosivity in terms of the "volume of erupted tephra" with a VEI of 0 corresponding to 10.    From Wordnik.com.  [RealClimate] Reference

1980, The interaction between volcanic gases and tephra.    From Wordnik.com.  [Volcanic Ash -- Effects on Water Supply and Mitigation Strategies] Reference

The radiocarbon dates on tephra F also appear anomalously old in the Laguna Chorreras core.    From Wordnik.com.  [Tephras in Ecuador « Climate Audit] Reference

1998, Agronomic impact of tephra fallout from 1995 and 1996 Ruapehu volcano eruptions, New Zealand.    From Wordnik.com.  [Actions to take for ash fall?] Reference

In fact, it's possible for scientists to tell from which hole in the volcano the tephra was taken. ".    From Wordnik.com.  [Blind Alley]

1982, Distribution, thickness, and mass of Late Pleistocene and Holocene tephra from major volcanoes in the northwestern.    From Wordnik.com.  [Actions to take for ash fall?] Reference

"When a volcano erupts the tephra sometimes forms a glass-like substance that can be polished and refined to resemble fine gems.    From Wordnik.com.  [Blind Alley]

1979, On the damage caused by volcanic eruptions with special reference to tephra and gases, in Sheets, P.D. and Grayson, D.K. (eds.).    From Wordnik.com.  [Volcanic Ash -- Effects on Water Supply and Mitigation Strategies] Reference

Ash is a fine form of tephra.    From Wordnik.com.  [The Iceland Weather Report] Reference

Later, rhyolitic tephra.    From Wordnik.com.  [Granophyre.html] Reference

Every volcano has its own signature tephra. ".    From Wordnik.com.  [Blind Alley]