Piplia Kalan meteorite, Pali District, Rajasthan (Rajputana), India

Eucrite, brecciated (monomict)
Fall, 20 June 1996; 42 kg


After three loud detonations were heard and a fireball seen through an overcast sky, two stones with masses of ~30 and 12 kg fell ~500 meters apart producing two small craters. The meteorite, a brecciated eucrite of the HED clan, contains ~ 70 vol% basaltic clasts in a subordinate fine-grained matrix. Pyroxene usually represents roughly 55-70% of the silicates with variations in reported findings presumably due both to inherent heterogeneity and to sampling problems. Usually classified as a monomict breccia, Piplia Kalan is dominated by disparate plagioclase-and-pyroxene rich lithologies of mildly variable composition — the plagioclase, for example, is largely equilibrated. However, a number of lithologies — mostly dominated by pigeonite, diopside, and bytownite — of widely varying textures, shapes and sizes have been reported. Relic glass provide additional evidence of early significant impacts. Six separate lithologies were identified by Shulka et al. (1997), but a later study by Buchanan et al., (2000) interpreted the meteorite in terms of two major lithologies and one minor lithology. Opaques include ilmenite, chromite, spinel, ulvospinel and other smaller, incompletely characterized phases. Textures and chemical signatures (Fe/Mn ratios; REE) further mark Piplia Kalan as one of several non-cumulate eucrites.

Samarium-Neodymium and Strontium-Rubidium ages indicate that Piplia Kalan comes from an ancient world formed nearly 4.6 billion years ago — presumably the asteroid Vesta. An Argon 39/40 age of ~3.5 billion years testifies to one unusually strong impact a billion years after formation. At the present time, meteoritics and planetary science are trying to piece together a more coherent picture of how and to what extent most meteorites in the Howardite-Eucrite-Diogenite (HED) Clan were produced on Vesta, subsequently ejected by impacts, and eventually transported to the earth. Piplia Kalan contains a few pertinent pieces of that very complex puzzle.

Mineral List

13 entries listed. 6 valid minerals.

References

External Links