Arriba meteorite, Lincoln County, Colorado, USAi

Regional Level Types
Arriba meteorite	Meteorite Fall Location
Lincoln County	County
Colorado	State
USA	Country

Ordinary chondrite, brecciated (L5,br)
Find, 1936; 31.1 kg

A single 15 kg stone broken into 3 pieces was found. It was reported after a listener heard a lecture about meteorites by a Nininger Laboratory representative. Four additional masses were recovered later (9.9 kg, 2.9 kg, 2.8 kg, 0.5 kg) in an area centered south of Arriba. Inspections reveal distinct chondrules and chondrule fragments within a largely equilibrated, but brecciated matrix. Compositionally, equilibrated olivine (Fa25) and low Ca-orthopyroxene ('hypersthene') are characteristic of the L-chondrite chemical group. Mineralogically, the meteorite consists primarily of olivine accompanied by orthopyroxene along with minor troilite and Fe-Ni metal. Accessory chromite, ilmenite, and phosphates have also been reported.

A reported U-He age of ~1.29 Ga may indicate a major intermediate parent body (IPB) collision during the last one or two eons.

As with many meteorites recovered in whole or in part by Harvey H. Nininger, a large mass is now held at the Arizona State University's Center for Meteorite Studies in Tempe [12.0199 kg in 2017].

Other Regions, Features and Areas containing this locality

References