Atoka meteorite, Atoka Co., Oklahoma, USA

Latitude & Longitude (WGS84):	34° 19' 0'' North , 96° 8' 59'' West
Latitude & Longitude (decimal):	34.31667,-96.15000
Non-native locality type:	Meteorite
Meteorite Class:	L6 chondrite meteorite
Meteoritical Society Class:	L6
Metbull:	View entry in Meteoritical Bulletin Database
Köppen climate type:	Cfa : Humid subtropical climate

Ordinary chondrite (L6)
Fell, 17 September 1945; 1.384 kg

Only a few weeks after the fall of the first atomic bomb, an alarmed witness saw an object fall into a drainage area just after some detonations. A day later, a life term prisoner from a nearby penitentiary dug out the harmless object. This and a few additional stones soon came into the hands of Oscar Monnig, the renown Texas meteorite collector. Inspections reveal a porous stone with moderately distinct chondrules and chondrule fragments within a largely lighter matrix. Compositionally, equilibrated olivine (Fa24) and associated orthopyroxene ('hypersthene') are characteristic of the L chondrite geochemical group. Mineralogically, the meteorite consists primarily of dominant olivine, pyroxene, troilite, and Fe-Ni metal. Accessory chromite, copper, and minor sulfides were observed by Ramdohr (1973). The presence of plessite may indicate a moderate level of shock heating.

The L (relatively low in total iron) chondrites are the largest group of ordinary chondrite falls and represent over 45% of the well classified chondrite falls and over 35% of all meteorite falls. The L6 petrologic type is the largest L chondrite subgroup. Atoka is one of 271 witnessed and named falls classified exactly as an ordinary L6 chondrite at the Meteoritical Society Database (November 2016). The main mass was originally part of the Monnig collection 910 grams which, apparently, still includes a complete stone of over 500 g housed at TCU. Most of the remaining mass has been at the United States National Museum in Washington (including a 330 g fragment).

Mineral List

7 valid minerals.

Meteorite/Rock Types Recorded

References

External Links