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Henry Spall

Publications and source records attributed to Henry Spall.

11 recordsLinked to original sources
USGS1989

Earthquakes & Volcanoes, Volume 21, Number 1, 1989: Featuring the U.S. Geological Survey's National Earthquake Information Center in Golden, Colorado, USA

Earthquakes and Volcanoes is published bimonthly by the U.S. Geological Survey to provide current information on earthquakes and seismology, volcanoes, and related natural hazards of interest to both generalized and specialized readers. The Secretary of the Interior has determined that the publication of this periodical is necessary in the transaction of the public business required by law of this Department. Use of funds for printing this periodical has been approved by the Office of Management and Budget through June 30, 1989. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

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USGS1988

Meers Fault, Oklahoma

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Earthquakes & Volcanoes (USGS)↗
USGS1988

Earthquake response

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Earthquakes & Volcanoes (USGS)↗
USGS1986

Meteoroids and impact craters

On a clear night scores of meteoroids streak across the sky. they leave light paths we call meteors or shooting stars as the Earth is showered with debris from distant parts of the solar system. When these meteoroids hit the Earth (as meteorites) they range in size from pebbles to the 34 ton Ahnighito meteorite that the American explorer Admiral Robert Peary discovered in Greenland. The unique importance of meteorites is that they have an extra-terrestrial origin and can provide us with direct evidence on the make-up of the solar system. They also give us clues to the origin of the solar system because they formed about 4.6 billion years ago at about the time the planets formed. Many meteoroids are associted with comets; as a comet travels around the sun it leaves a trail of debris behind it and it is this debris which produces meteor showers. Other meteoroids come from the asteroid belt, a zone between Mars and Jupiter filled with thousands of dwarf worlds that failed to coalesce into planets.

Earthquakes & Volcanoes (USGS)↗