Monthly Favourite Meteorite (Gao-Guenie)

Gao-Guenie

The Gao-Guenie meteorite fell on March 5^th, 1960 at 5:00pm local time. The fall occurred over an area which was formerly called Upper Volta in Africa. This meteorite was classified as an Ordinary Chondrite, H5. Many thousands of stones rained down over the area and the Total Known Weight is not exactly known but probably several hundred kilograms. It was originally reported that there were two showers occurring a month apart and therefore had two different names. One was Gao (Upper Volta) and the other Guenie. It was later realised that they both belonged to the same fall and renamed to the current collective; Gao-Guenie. One reason for this may have happened is because the strewn field was very large (70 - 75 sq. kilometres) and irregular. It has been suggested that on entry through Earth's atmosphere, fragmentation may have taken place three separate times. These occurred high enough to continue the intense heating and prompt the explosions or fragmenting but also formed the beautiful fresh stones for us to find on the ground. One of the more interesting factors to come from this fall was the discovery of Impact Melts in some of the pieces (less than 1%). This is an extremely rare thing to find among such a large number of normal stones. In the piece below you can clearly see how the metal has been melted and elongated by the shock of the impact with another body. The following pieces are part of the Meteorites Australia Collection.

Gao-Guenie (H5) - 102g Oriented Individual.

Gao-Guenie (H5) - 12.97g Oriented Individual.

Gao-Guenie (H5) - 2.70g Oriented Individual.

Gao-Guenie (H5) - 4.74g Individual.

Map produced by United States Central Intelligence Agency. Courtesy of The University of Texas.
Burkina Faso, Africa. Gao-Guenie meteorite fall location.

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