Abstract
In 1994 a moving car and its driver, on a highway in southern Madrid (Getafe), were struck by a falling rock. Eighty-one additional fragments (total weight : 55.926 kg) were later recovered, which all pointed towards a meteorite fall. A study of the composition of this object revealed an ultrarefractory material displaying a most unusual chemical make-up which differs from any known meteorite class, and for some elements and minerals approaches the composition of CAI (Ca-Al-rich inclusions in chondrites). A study of some cosmic-ray-produced stable and radioactive nuclides indicates: a) space and terrestrial exposure ages which do not exceed 1,000 and 520,000 years, respectively; b) the presence of a small 22Ne excess (1,100°C fraction), which suggests either a nucleogenic contribution from the 19F(α,n)22Ne reaction or a trapped Ne signature distinct from atmospheric Ne, and c) the existence of minor variations in the 38Ar/36Ar ratios also indicating a nucleogenic component or fractionation effects. 14C data are consistent with "modern" carbon originated in the period 1955-1958 and not earlier or more recently. The possibility that the Getafe rock could have a man-made origin (i.e. ceramic and refractory tiles, industrial slag) is also considered.
Original language | English (US) |
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Pages (from-to) | 308-314 |
Number of pages | 7 |
Journal | Revista de Metalurgia (Madrid) |
Volume | 35 |
Issue number | 5 |
DOIs | |
State | Published - 1999 |
Keywords
- Composition
- Cosmic ray records
- Fall
- Getafe rock
- Madrid
- Meteorite
- Slag
- Spain
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Metals and Alloys
- Materials Chemistry